ovs-vswitchd.conf.db(5) Open vSwitch Manual ovs-vswitchd.conf.db(5)
NAME
ovs-vswitchd.conf.db - Open_vSwitch database schema
A database with this schema holds the configuration for one Open
vSwitch daemon. The top-level configuration for the daemon is the
Open_vSwitch table, which must have exactly one record. Records in
other tables are significant only when they can be reached directly or
indirectly from the Open_vSwitch table. Records that are not reachable
from the Open_vSwitch table are automatically deleted from the data‐
base, except for records in a few distinguished ``root set’’ tables.
Common Columns
Most tables contain two special columns, named other_config and exter‐
nal_ids. These columns have the same form and purpose each place that
they appear, so we describe them here to save space later.
other_config: map of string-string pairs
Key-value pairs for configuring rarely used features.
Supported keys, along with the forms taken by their val‐
ues, are documented individually for each table.
A few tables do not have other_config columns because no
key-value pairs have yet been defined for them.
external_ids: map of string-string pairs
Key-value pairs for use by external frameworks that inte‐
grate with Open vSwitch, rather than by Open vSwitch it‐
self. System integrators should either use the Open
vSwitch development mailing list to coordinate on common
key-value definitions, or choose key names that are
likely to be unique. In some cases, where key-value pairs
have been defined that are likely to be widely useful,
they are documented individually for each table.
TABLE SUMMARY
The following list summarizes the purpose of each of the tables in the
Open_vSwitch database. Each table is described in more detail on a
later page.
Table Purpose
Open_vSwitch
Open vSwitch configuration.
Bridge Bridge configuration.
Port Port configuration.
Interface One physical network device in a Port.
Flow_Table
OpenFlow table configuration
QoS Quality of Service configuration
Queue QoS output queue.
Mirror Port mirroring.
Controller
OpenFlow controller configuration.
Manager OVSDB management connection.
NetFlow NetFlow configuration.
Datapath Datapath configuration.
CT_Zone CT_Zone configuration.
CT_Timeout_Policy
CT_Timeout_Policy configuration.
SSL SSL configuration.
sFlow sFlow configuration.
IPFIX IPFIX configuration.
Flow_Sample_Collector_Set
Flow_Sample_Collector_Set configuration.
AutoAttach
AutoAttach configuration.
Open_vSwitch TABLE
Configuration for an Open vSwitch daemon. There must be exactly one
record in the Open_vSwitch table.
Summary:
Configuration:
datapaths map of string-Datapath pairs
bridges set of Bridges
ssl optional SSL
external_ids : system-id optional string
external_ids : hostname optional string
external_ids : rundir optional string
other_config : stats-update-interval
optional string, containing an integer,
at least 5,000
other_config : flow-restore-wait
optional string, either true or false
other_config : flow-limit optional string, containing an integer,
at least 0
other_config : max-idle optional string, containing an integer,
at least 500
other_config : max-revalidator
optional string, containing an integer,
at least 100
other_config : min-revalidate-pps
optional string, containing an integer,
at least 0
other_config : offloaded-stats-delay
optional string, containing an integer,
at least 0
other_config : hw-offload optional string, either true or false
other_config : n-offload-threads
optional string, containing an integer,
in range 1 to 10
other_config : tc-policy optional string, one of none, skip_hw, or
skip_sw
other_config : dpdk-init optional string, one of false, true, or
try
other_config : dpdk-lcore-mask
optional string, containing an integer,
at least 1
other_config : pmd-cpu-mask
optional string
other_config : dpdk-alloc-mem
optional string, containing an integer,
at least 0
other_config : dpdk-socket-mem
optional string
other_config : dpdk-socket-limit
optional string
other_config : dpdk-hugepage-dir
optional string
other_config : dpdk-extra optional string
other_config : vhost-sock-dir
optional string
other_config : vhost-iommu-support
optional string, either true or false
other_config : vhost-postcopy-support
optional string, either true or false
other_config : per-port-memory
optional string, either true or false
other_config : shared-mempool-config
optional string
other_config : tx-flush-interval
optional string, containing an integer,
in range 0 to 1,000,000
other_config : pmd-perf-metrics
optional string, either true or false
other_config : smc-enable optional string, either true or false
other_config : pmd-rxq-assign
optional string, one of cycles, group, or
roundrobin
other_config : pmd-rxq-isolate
optional string, either true or false
other_config : n-handler-threads
optional string, containing an integer,
at least 1
other_config : n-revalidator-threads
optional string, containing an integer,
at least 1
other_config : emc-insert-inv-prob
optional string, containing an integer,
in range 0 to 4,294,967,295
other_config : vlan-limit optional string, containing an integer,
at least 0
other_config : bundle-idle-timeout
optional string, containing an integer,
at least 1
other_config : offload-rebalance
optional string, either true or false
other_config : pmd-auto-lb optional string, either true or false
other_config : pmd-auto-lb-rebal-interval
optional string, containing an integer,
in range 0 to 20,000
other_config : pmd-auto-lb-load-threshold
optional string, containing an integer,
in range 0 to 100
other_config : pmd-auto-lb-improvement-threshold
optional string, containing an integer,
in range 0 to 100
other_config : pmd-sleep-max
optional string
other_config : userspace-tso-enable
optional string, either true or false
other_config : explicit-sampled-drops
optional string, either true or false
Status:
next_cfg integer
cur_cfg integer
dpdk_initialized boolean
Statistics:
other_config : enable-statistics
optional string, either true or false
statistics : cpu optional string, containing an integer,
at least 1
statistics : load_average
optional string
statistics : memory optional string
statistics : process_NAME
optional string
statistics : file_systems
optional string
Version Reporting:
ovs_version optional string
db_version optional string
system_type optional string
system_version optional string
dpdk_version optional string
Capabilities:
datapath_types set of strings
iface_types set of strings
Database Configuration:
manager_options set of Managers
IPsec:
other_config : private_key optional string
other_config : certificate optional string
other_config : ca_cert optional string
Plaintext Tunnel Policy:
other_config : ipsec_skb_mark
optional string
Common Columns:
other_config map of string-string pairs
external_ids map of string-string pairs
Details:
Configuration:
datapaths: map of string-Datapath pairs
Map of datapath types to datapaths. The datapath_type column of
the Bridge table is used as a key for this map. The value points
to a row in the Datapath table.
bridges: set of Bridges
Set of bridges managed by the daemon.
ssl: optional SSL
SSL used globally by the daemon.
external_ids : system-id: optional string
A unique identifier for the Open vSwitch’s physical host. The
form of the identifier depends on the type of the host.
external_ids : hostname: optional string
The hostname for the host running Open vSwitch. This is a fully
qualified domain name since version 2.6.2.
external_ids : rundir: optional string
In Open vSwitch 2.8 and later, the run directory of the running
Open vSwitch daemon. This directory is used for runtime state
such as control and management sockets. The value of other_con‐
fig:vhost-sock-dir is relative to this directory.
other_config : stats-update-interval: optional string, containing an
integer, at least 5,000
Interval for updating statistics to the database, in millisec‐
onds. This option will affect the update of the statistics col‐
umn in the following tables: Port, Interface , Mirror.
Default value is 5000 ms.
Getting statistics more frequently can be achieved via OpenFlow.
other_config : flow-restore-wait: optional string, either true or false
When ovs-vswitchd starts up, it has an empty flow table and
therefore it handles all arriving packets in its default fashion
according to its configuration, by dropping them or sending them
to an OpenFlow controller or switching them as a standalone
switch. This behavior is ordinarily desirable. However, if
ovs-vswitchd is restarting as part of a ``hot-upgrade,’’ then
this leads to a relatively long period during which packets are
mishandled.
This option allows for improvement. When ovs-vswitchd starts
with this value set as true, it will neither flush or expire
previously set datapath flows nor will it send and receive any
packets to or from the datapath. When this value is later set to
false, ovs-vswitchd will start receiving packets from the data‐
path and re-setup the flows.
Additionally, ovs-vswitchd is prevented from connecting to con‐
trollers when this value is set to true. This prevents con‐
trollers from making changes to the flow table in the middle of
flow restoration, which could result in undesirable intermediate
states. Once this value has been set to false and the desired
flow state has been restored, ovs-vswitchd will be able to re‐
connect to controllers and process any new flow table modifica‐
tions.
Thus, with this option, the procedure for a hot-upgrade of
ovs-vswitchd becomes roughly the following:
1. Stop ovs-vswitchd.
2. Set other_config:flow-restore-wait to true.
3. Start ovs-vswitchd.
4. Use ovs-ofctl (or some other program, such as an OpenFlow
controller) to restore the OpenFlow flow table to the de‐
sired state.
5. Set other_config:flow-restore-wait to false (or remove it
entirely from the database).
The ovs-ctl’s ``restart’’ and ``force-reload-kmod’’ functions
use the above config option during hot upgrades.
other_config : flow-limit: optional string, containing an integer, at
least 0
The maximum number of flows allowed in the datapath flow table.
Internally OVS will choose a flow limit which will likely be
lower than this number, based on real time network conditions.
Tweaking this value is discouraged unless you know exactly what
you’re doing.
The default is 200000.
other_config : max-idle: optional string, containing an integer, at
least 500
The maximum time (in ms) that idle flows will remain cached in
the datapath. Internally OVS will check the validity and activ‐
ity for datapath flows regularly and may expire flows quicker
than this number, based on real time network conditions. Tweak‐
ing this value is discouraged unless you know exactly what
you’re doing.
The default is 10000.
other_config : max-revalidator: optional string, containing an integer,
at least 100
The maximum time (in ms) that revalidator threads will wait be‐
fore executing flow revalidation. Note that this is maximum al‐
lowed value. Actual timeout used by OVS is minimum of max-idle
and max-revalidator values. Tweaking this value is discouraged
unless you know exactly what you’re doing.
The default is 500.
other_config : min-revalidate-pps: optional string, containing an inte‐
ger, at least 0
Set minimum pps that flow must have in order to be revalidated
when revalidation duration exceeds half of max-revalidator con‐
fig variable. Setting to 0 means always revalidate flows regard‐
less of pps.
The default is 5.
other_config : offloaded-stats-delay: optional string, containing an
integer, at least 0
Set worst case delay (in ms) it might take before statistics of
offloaded flows are updated. Offloaded flows younger than this
delay will always be revalidated regardless of other_config:min-
revalidate-pps.
The default is 2000.
other_config : hw-offload: optional string, either true or false
Set this value to true to enable netdev flow offload.
The default value is false. Changing this value requires
restarting the daemon
Currently Open vSwitch supports hardware offloading on Linux
systems. On other systems, this value is ignored. This function‐
ality is considered ’experimental’. Depending on which OpenFlow
matches and actions are configured, which kernel version is
used, and what hardware is available, Open vSwitch may not be
able to offload functionality to hardware.
In order to dump HW offloaded flows use ovs-appctl
dpctl/dump-flows, ovs-dpctl doesn’t support this functionality.
See ovs-vswitchd(8) for details.
other_config : n-offload-threads: optional string, containing an inte‐
ger, in range 1 to 10
Set this value to the number of threads created to manage hard‐
ware offloads.
The default value is 1. Changing this value requires restarting
the daemon.
This is only relevant for userspace datapath and only if
other_config:hw-offload is enabled.
other_config : tc-policy: optional string, one of none, skip_hw, or
skip_sw
Specified the policy used with HW offloading. Options:
none Add software rule and offload rule to HW.
skip_sw
Offload rule to HW only.
skip_hw
Add software rule without offloading rule to HW.
This is only relevant if other_config:hw-offload is enabled.
The default value is none.
other_config : dpdk-init: optional string, one of false, true, or try
Set this value to true or try to enable runtime support for DPDK
ports. The vswitch must have compile-time support for DPDK as
well.
A value of true will cause the ovs-vswitchd process to abort if
DPDK cannot be initialized. A value of try will allow the ovs-
vswitchd process to continue running even if DPDK cannot be ini‐
tialized.
The default value is false. Changing this value requires
restarting the daemon
If this value is false at startup, any dpdk ports which are con‐
figured in the bridge will fail due to memory errors.
other_config : dpdk-lcore-mask: optional string, containing an integer,
at least 1
Specifies the CPU cores where dpdk lcore threads should be
spawned. The DPDK lcore threads are used for DPDK library tasks,
such as library internal message processing, logging, etc. Value
should be in the form of a hex string (so ’0x123’) similar to
the ’taskset’ mask input.
The lowest order bit corresponds to the first CPU core. A set
bit means the corresponding core is available and an lcore
thread will be created and pinned to it. If the input does not
cover all cores, those uncovered cores are considered not set.
For performance reasons, it is best to set this to a single core
on the system, rather than allow lcore threads to float.
If not specified, the value will be determined by choosing the
lowest CPU core from initial cpu affinity list. Otherwise, the
value will be passed directly to the DPDK library.
other_config : pmd-cpu-mask: optional string
Specifies CPU mask for setting the cpu affinity of PMD (Poll
Mode Driver) threads. Value should be in the form of hex string,
similar to the dpdk EAL ’-c COREMASK’ option input or the
’taskset’ mask input.
The lowest order bit corresponds to the first CPU core. A set
bit means the corresponding core is available and a pmd thread
will be created and pinned to it. If the input does not cover
all cores, those uncovered cores are considered not set.
If not specified, one pmd thread will be created for each numa
node and pinned to any available core on the numa node by de‐
fault.
other_config : dpdk-alloc-mem: optional string, containing an integer,
at least 0
Specifies the amount of memory to preallocate from the hugepage
pool, regardless of socket. It is recommended that dpdk-socket-
mem is used instead.
other_config : dpdk-socket-mem: optional string
Specifies the amount of memory to preallocate from the hugepage
pool, on a per-socket basis.
The specifier is a comma-separated string, in ascending order of
CPU socket. E.g. On a four socket system 1024,0,2048 would set
socket 0 to preallocate 1024MB, socket 1 to preallocate 0MB,
socket 2 to preallocate 2048MB and socket 3 (no value given) to
preallocate 0MB.
If other_config:dpdk-socket-mem and other_config:dpdk-alloc-mem
are not specified, neither will be used and there will be no de‐
fault value for each numa node. DPDK defaults will be used in‐
stead. If other_config:dpdk-socket-mem and other_config:dpdk-al‐
loc-mem are specified at the same time, other_config:dpdk-
socket-mem will be used as default. Changing this value requires
restarting the daemon.
other_config : dpdk-socket-limit: optional string
Limits the maximum amount of memory that can be used from the
hugepage pool, on a per-socket basis.
The specifier is a comma-separated list of memory limits per
socket. 0 will disable the limit for a particular socket.
If not specified, OVS will not configure limits by default.
Changing this value requires restarting the daemon.
other_config : dpdk-hugepage-dir: optional string
Specifies the path to the hugetlbfs mount point.
If not specified, this will be guessed by the DPDK library (de‐
fault is /dev/hugepages). Changing this value requires restart‐
ing the daemon.
other_config : dpdk-extra: optional string
Specifies additional eal command line arguments for DPDK.
The default is empty. Changing this value requires restarting
the daemon
other_config : vhost-sock-dir: optional string
Specifies a relative path from external_ids:rundir to the vhost-
user unix domain socket files. If this value is unset, the sock‐
ets are put directly in external_ids:rundir.
Changing this value requires restarting the daemon.
other_config : vhost-iommu-support: optional string, either true or
false
vHost IOMMU is a security feature, which restricts the vhost
memory that a virtio device may access. vHost IOMMU support is
disabled by default, due to a bug in QEMU implementations of the
vhost REPLY_ACK protocol, (on which vHost IOMMU relies) prior to
v2.9.1. Setting this value to true enables vHost IOMMU support
for vHost User Client ports in OvS-DPDK, starting from DPDK
v17.11.
Changing this value requires restarting the daemon.
other_config : vhost-postcopy-support: optional string, either true or
false
vHost post-copy is a feature which allows switching live migra‐
tion of VM attached to dpdkvhostuserclient port to post-copy
mode if default pre-copy migration can not be converged or takes
too long to converge. Setting this value to true enables vHost
post-copy support for all dpdkvhostuserclient ports. Available
starting from DPDK v18.11 and QEMU 2.12.
Changing this value requires restarting the daemon.
other_config : per-port-memory: optional string, either true or false
By default OVS DPDK uses a shared memory model wherein devices
that have the same MTU and socket values can share the same mem‐
pool. Setting this value to true changes this behaviour. Per
port memory allow DPDK devices to use private memory per device.
This can provide greater transparency as regards memory usage
but potentially at the cost of greater memory requirements.
Changing this value requires restarting the daemon if dpdk-init
has already been set to true.
other_config : shared-mempool-config: optional string
Specifies dpdk shared mempool config.
Value should be set in the following form:
other_config:shared-mempool-config=< user-shared-mem‐
pool-mtu-list>
where
• <user-shared-mempool-mtu-list> ::= NULL | <non-empty-
list>
• <non-empty-list> ::= <user-mtus> | <user-mtus> , <non-
empty-list>
• <user-mtus> ::= <mtu-all-socket> | <mtu-socket-pair>
• <mtu-all-socket> ::= <mtu>
• <mtu-socket-pair> ::= <mtu> : <socket-id>
Changing this value requires restarting the daemon if dpdk-init
has already been set to true.
other_config : tx-flush-interval: optional string, containing an inte‐
ger, in range 0 to 1,000,000
Specifies the time in microseconds that a packet can wait in
output batch for sending i.e. amount of time that packet can
spend in an intermediate output queue before sending to netdev.
This option can be used to configure balance between throughput
and latency. Lower values decreases latency while higher values
may be useful to achieve higher performance.
Defaults to 0 i.e. instant packet sending (latency optimized).
other_config : pmd-perf-metrics: optional string, either true or false
Enables recording of detailed PMD performance metrics for analy‐
sis and trouble-shooting. This can have a performance impact in
the order of 1%.
Defaults to false but can be changed at any time.
other_config : smc-enable: optional string, either true or false
Signature match cache or SMC is a cache between EMC and megaflow
cache. It does not store the full key of the flow, so it is more
memory efficient comparing to EMC cache. SMC is especially use‐
ful when flow count is larger than EMC capacity.
Defaults to false but can be changed at any time.
other_config : pmd-rxq-assign: optional string, one of cycles, group,
or roundrobin
Specifies how RX queues will be automatically assigned to CPU
cores. Options:
cycles Rxqs will be sorted by order of measured processing cy‐
cles before being assigned to CPU cores.
roundrobin
Rxqs will be round-robined across CPU cores.
group Rxqs will be sorted by order of measured processing cy‐
cles before being assigned to CPU cores with lowest esti‐
mated load.
The default value is cycles.
Changing this value will affect an automatic re-assignment of
Rxqs to CPUs. Note: Rxqs mapped to CPU cores with pmd-rxq-affin‐
ity are unaffected.
other_config : pmd-rxq-isolate: optional string, either true or false
Specifies if a CPU core will be isolated after being pinned with
an Rx queue.
Set this value to false to non-isolate a CPU core after it is
pinned with an Rxq using pmd-rxq-affinity. This will allow OVS
to assign other Rxqs to that CPU core.
The default value is true.
This can only be false when pmd-rxq-assign is set to group.
other_config : n-handler-threads: optional string, containing an inte‐
ger, at least 1
Attempts to specify the number of threads for software datapaths
to use for handling new flows. Some datapaths may choose to ig‐
nore this and it will be set to a sensible option for the data‐
path type.
This configuration is per datapath. If you have more than one
software datapath (e.g. some system bridges and some netdev
bridges), then the total number of threads is n-handler-threads
times the number of software datapaths.
other_config : n-revalidator-threads: optional string, containing an
integer, at least 1
Attempts to specify the number of threads for software datapaths
to use for revalidating flows in the datapath. Some datapaths
may choose to ignore this and will set to a sensible option for
the datapath type.
Typically, there is a direct correlation between the number of
revalidator threads, and the number of flows allowed in the
datapath. The default is the number of cpu cores divided by four
plus one. If n-handler-threads is set, the default changes to
the number of cpu cores minus the number of handler threads.
This configuration is per datapath. If you have more than one
software datapath (e.g. some system bridges and some netdev
bridges), then the total number of threads is n-handler-threads
times the number of software datapaths.
other_config : emc-insert-inv-prob: optional string, containing an in‐
teger, in range 0 to 4,294,967,295
Specifies the inverse probability (1/emc-insert-inv-prob) of a
flow being inserted into the Exact Match Cache (EMC). On average
one in every emc-insert-inv-prob packets that generate a unique
flow will cause an insertion into the EMC. A value of 1 will re‐
sult in an insertion for every flow (1/1 = 100%) whereas a value
of zero will result in no insertions and essentially disable the
EMC.
Defaults to 100 ie. there is (1/100 =) 1% chance of EMC inser‐
tion.
other_config : vlan-limit: optional string, containing an integer, at
least 0
Limits the number of VLAN headers that can be matched to the
specified number. Further VLAN headers will be treated as pay‐
load, e.g. a packet with more 802.1q headers will match Ethernet
type 0x8100.
Open vSwitch userspace currently supports at most 2 VLANs, and
each datapath has its own limit. If vlan-limit is nonzero, it
acts as a further limit.
If this value is absent, the default is currently 1. This main‐
tains backward compatibility with controllers that were designed
for use with Open vSwitch versions earlier than 2.8, which only
supported one VLAN.
other_config : bundle-idle-timeout: optional string, containing an in‐
teger, at least 1
The maximum time (in seconds) that idle bundles will wait to be
expired since it was either opened, modified or closed.
OpenFlow specification mandates the timeout to be at least one
second. The default is 10 seconds.
other_config : offload-rebalance: optional string, either true or false
Configures HW offload rebalancing, that allows to dynamically
offload and un-offload flows while an offload-device is out of
resources (OOR). This policy allows flows to be selected for of‐
floading based on the packets-per-second (pps) rate of flows.
Set this value to true to enable this option.
The default value is false. Changing this value requires
restarting the daemon.
This is only relevant if HW offloading is enabled (hw-offload).
When this policy is enabled, it also requires ’tc-policy’ to be
set to ’skip_sw’.
other_config : pmd-auto-lb: optional string, either true or false
Configures PMD Auto Load Balancing that allows automatic assign‐
ment of RX queues to PMDs if any of PMDs is overloaded (i.e. a
processing cycles > other_config:pmd-auto-lb-load-threshold).
It uses current scheme of cycle based assignment of RX queues
that are not statically pinned to PMDs.
The default value is false.
Set this value to true to enable this option. It is currently
disabled by default and an experimental feature.
This only comes in effect if cycle based assignment is enabled
and there are more than one non-isolated PMDs present and at
least one of it polls more than one queue.
other_config : pmd-auto-lb-rebal-interval: optional string, containing
an integer, in range 0 to 20,000
The minimum time (in minutes) 2 consecutive PMD Auto Load Bal‐
ancing iterations.
The default value is 1 min. If configured to 0 then it would be
converted to default value i.e. 1 min
This option can be configured to avoid frequent trigger of auto
load balancing of PMDs. For e.g. set the value (in min) such
that it occurs once in few hours or a day or a week.
other_config : pmd-auto-lb-load-threshold: optional string, containing
an integer, in range 0 to 100
Specifies the minimum PMD thread load threshold (% of used cy‐
cles) of any non-isolated PMD threads when a PMD Auto Load Bal‐
ance may be triggered.
The default value is 95%.
other_config : pmd-auto-lb-improvement-threshold: optional string, con‐
taining an integer, in range 0 to 100
Specifies the minimum evaluated % improvement in load distribu‐
tion across the non-isolated PMD threads that will allow a PMD
Auto Load Balance to occur.
Note, setting this parameter to 0 will always allow an auto load
balance to occur regardless of estimated improvement or not.
The default value is 25%.
other_config : pmd-sleep-max: optional string
Specifies the maximum sleep time that will be requested in mi‐
croseconds per iteration for a PMD thread which has received
zero or a small amount of packets from the Rx queues it is
polling.
The actual sleep time requested is based on the load of the Rx
queues that the PMD polls and may be less than the maximum
value.
The default value is 0 microseconds, which means that the PMD
will not sleep regardless of the load from the Rx queues that it
polls.
The maximum value is 10000 microseconds.
other_config:pmd-sleep-max=<pmd-sleep-list>
where
• <pmd-sleep-list> ::= NULL | <non-empty-list>
• <non-empty-list> ::= <pmd-sleep-value> | <pmd-sleep-
value> , <non-empty-list>
• <pmd-sleep-value> ::= <global-default-sleep-value> |
<pmd-core-sleep-pair>
• <global-default-sleep-value> ::= <max-sleep-time>
• <pmd-core-sleep-pair> ::= <core> : <max-sleep-time>
other_config : userspace-tso-enable: optional string, either true or
false
Set this value to true to enable userspace support for TCP Seg‐
mentation Offloading (TSO). When it is enabled, the interfaces
can provide an oversized TCP segment to the datapath and the
datapath will offload the TCP segmentation and checksum calcula‐
tion to the interfaces when necessary.
The default value is false. Changing this value requires
restarting the daemon.
The feature only works if Open vSwitch is built with DPDK sup‐
port.
The feature is considered experimental.
other_config : explicit-sampled-drops: optional string, either true or
false
When a flow is installed in the datapath with an empty action
list, it indicates an implicit "drop" action. Most datapaths re‐
port this for event for statistics and monitoring (in datapath-
specific ways).
However, if any of the per-bridge or per-flow sampling function‐
alities are enabled (e.g: sFlow, IPFIX, local sampling), the ac‐
tion list might not be empty, but contain an action to implement
such functionality. This makes the datapaths not report the
packet drop.
This knob makes Open vSwitch detect when the last datapath ac‐
tion comes from these sampling features and add an explicit drop
action at the end to keep drop statistics accurate.
The default value is false.
Status:
next_cfg: integer
Sequence number for client to increment. When a client modifies
any part of the database configuration and wishes to wait for
Open vSwitch to finish applying the changes, it may increment
this sequence number.
cur_cfg: integer
Sequence number that Open vSwitch sets to the current value of
next_cfg after it finishes applying a set of configuration
changes.
dpdk_initialized: boolean
True if other_config:dpdk-init is set to true and the DPDK li‐
brary is successfully initialized.
Statistics:
The statistics column contains key-value pairs that report statistics
about a system running an Open vSwitch. These are updated periodically
(currently, every 5 seconds). Key-value pairs that cannot be determined
or that do not apply to a platform are omitted.
other_config : enable-statistics: optional string, either true or false
Statistics are disabled by default to avoid overhead in the com‐
mon case when statistics gathering is not useful. Set this value
to true to enable populating the statistics column or to false
to explicitly disable it.
statistics : cpu: optional string, containing an integer, at least 1
Number of CPU processors, threads, or cores currently online and
available to the operating system on which Open vSwitch is run‐
ning, as an integer. This may be less than the number installed,
if some are not online or if they are not available to the oper‐
ating system.
Open vSwitch userspace processes are not multithreaded, but the
Linux kernel-based datapath is.
statistics : load_average: optional string
A comma-separated list of three floating-point numbers, repre‐
senting the system load average over the last 1, 5, and 15 min‐
utes, respectively.
statistics : memory: optional string
A comma-separated list of integers, each of which represents a
quantity of memory in kilobytes that describes the operating
system on which Open vSwitch is running. In respective order,
these values are:
1. Total amount of RAM allocated to the OS.
2. RAM allocated to the OS that is in use.
3. RAM that can be flushed out to disk or otherwise discarded
if that space is needed for another purpose. This number is
necessarily less than or equal to the previous value.
4. Total disk space allocated for swap.
5. Swap space currently in use.
On Linux, all five values can be determined and are included. On
other operating systems, only the first two values can be deter‐
mined, so the list will only have two values.
statistics : process_NAME: optional string
One such key-value pair, with NAME replaced by a process name,
will exist for each running Open vSwitch daemon process, with
name replaced by the daemon’s name (e.g. process_ovs-vswitchd).
The value is a comma-separated list of integers. The integers
represent the following, with memory measured in kilobytes and
durations in milliseconds:
1. The process’s virtual memory size.
2. The process’s resident set size.
3. The amount of user and system CPU time consumed by the
process.
4. The number of times that the process has crashed and been
automatically restarted by the monitor.
5. The duration since the process was started.
6. The duration for which the process has been running.
The interpretation of some of these values depends on whether
the process was started with the --monitor. If it was not, then
the crash count will always be 0 and the two durations will al‐
ways be the same. If --monitor was given, then the crash count
may be positive; if it is, the latter duration is the amount of
time since the most recent crash and restart.
There will be one key-value pair for each file in Open vSwitch’s
``run directory’’ (usually /var/run/openvswitch) whose name ends
in .pid, whose contents are a process ID, and which is locked by
a running process. The name is taken from the pidfile’s name.
Currently Open vSwitch is only able to obtain all of the above
detail on Linux systems. On other systems, the same key-value
pairs will be present but the values will always be the empty
string.
statistics : file_systems: optional string
A space-separated list of information on local, writable file
systems. Each item in the list describes one file system and
consists in turn of a comma-separated list of the following:
1. Mount point, e.g. / or /var/log. Any spaces or commas in the
mount point are replaced by underscores.
2. Total size, in kilobytes, as an integer.
3. Amount of storage in use, in kilobytes, as an integer.
This key-value pair is omitted if there are no local, writable
file systems or if Open vSwitch cannot obtain the needed infor‐
mation.
Version Reporting:
These columns report the types and versions of the hardware and soft‐
ware running Open vSwitch. We recommend in general that software should
test whether specific features are supported instead of relying on ver‐
sion number checks. These values are primarily intended for reporting
to human administrators.
ovs_version: optional string
The Open vSwitch version number, e.g. 1.1.0.
db_version: optional string
The database schema version number, e.g. 1.2.3. See ovsdb-
tool(1) for an explanation of the numbering scheme.
The schema version is part of the database schema, so it can
also be retrieved by fetching the schema using the Open vSwitch
database protocol.
system_type: optional string
An identifier for the type of system on top of which Open
vSwitch runs, e.g. KVM.
System integrators are responsible for choosing and setting an
appropriate value for this column.
system_version: optional string
The version of the system identified by system_type, e.g.
4.18.0-372.19.1.el8_6 on RHEL 8.6 with kernel 4.18.0-372.19.1.
System integrators are responsible for choosing and setting an
appropriate value for this column.
dpdk_version: optional string
The version of the linked DPDK library.
Capabilities:
These columns report capabilities of the Open vSwitch instance.
datapath_types: set of strings
This column reports the different dpifs registered with the sys‐
tem. These are the values that this instance supports in the
datapath_type column of the Bridge table.
iface_types: set of strings
This column reports the different netdevs registered with the
system. These are the values that this instance supports in the
type column of the Interface table.
Database Configuration:
These columns primarily configure the Open vSwitch database
(ovsdb-server), not the Open vSwitch switch (ovs-vswitchd). The OVSDB
database also uses the ssl settings.
The Open vSwitch switch does read the database configuration to deter‐
mine remote IP addresses to which in-band control should apply.
manager_options: set of Managers
Database clients to which the Open vSwitch database server
should connect or to which it should listen, along with options
for how these connections should be configured. See the Manager
table for more information.
For this column to serve its purpose, ovsdb-server must be con‐
figured to honor it. The easiest way to do this is to invoke
ovsdb-server with the option --re‐
mote=db:Open_vSwitch,Open_vSwitch,manager_options The startup
scripts that accompany Open vSwitch do this by default.
IPsec:
These settings control the global configuration of IPsec tunnels. The
options column of the Interface table configures IPsec for individual
tunnels. The options column also allows for custom options prefixed
with ipsec_ to be passed to the individual connections.
OVS IPsec supports the following three forms of authentication. Cur‐
rently, all IPsec tunnels must use the same form:
1. Pre-shared keys: Omit the global settings. On each tunnel,
set options:psk.
2. Self-signed certificates: Set the private_key and certifi‐
cate global settings. On each tunnel, set options:re‐
mote_cert. The remote certificate can be self-signed.
3. CA-signed certificates: Set all of the global settings. On
each tunnel, set options:remote_name to the common name (CN)
of the remote certificate. The remote certificate must be
signed by the CA.
other_config : private_key: optional string
Name of a PEM file containing the private key used as the
switch’s identity for IPsec tunnels.
other_config : certificate: optional string
Name of a PEM file containing a certificate that certifies the
switch’s private key, and identifies a trustworthy switch for
IPsec tunnels. The certificate must be x.509 version 3 and with
the string in common name (CN) also set in the subject alterna‐
tive name (SAN).
other_config : ca_cert: optional string
Name of a PEM file containing the CA certificate used to verify
that a remote switch of the IPsec tunnel is trustworthy.
Plaintext Tunnel Policy:
When an IPsec tunnel is configured in this database, multiple indepen‐
dent components take responsibility for implementing it. ovs-vswitchd
and its datapath handle packet forwarding to the tunnel and a separate
daemon pushes the tunnel’s IPsec policy configuration to the kernel or
other entity that implements it. There is a race: if the former config‐
uration completes before the latter, then packets sent by the local
host over the tunnel can be transmitted in plaintext. Using this set‐
ting, OVS users can avoid this undesirable situation.
other_config : ipsec_skb_mark: optional string
This setting takes the form value/mask. If it is specified, then
the skb_mark field in every outgoing tunneled packet sent in
plaintext is compared against it and, if it matches, the packet
is dropped. This is a global setting that is applied to every
tunneled packet, regardless of whether IPsec encryption is en‐
abled for the tunnel, the type of tunnel, or whether OVS is in‐
volved.
Example policies:
1/1 Drop all unencrypted tunneled packets in which the least-
significant bit of skb_mark is 1. This would be a useful
policy given an OpenFlow flow table that sets skb_mark to
1 for traffic that should be encrypted. The default
skb_mark is 0, so this would not affect other traffic.
0/1 Drop all unencrypted tunneled packets in which the least-
significant bit of skb_mark is 0. This would be a useful
policy if no unencrypted tunneled traffic should exit the
system without being specially permitted by setting
skb_mark to 1.
(empty)
If this setting is empty or unset, then all unencrypted
tunneled packets are transmitted in the usual way.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
other_config: map of string-string pairs
external_ids: map of string-string pairs
Bridge TABLE
Configuration for a bridge within an Open_vSwitch.
A Bridge record represents an Ethernet switch with one or more
``ports,’’ which are the Port records pointed to by the Bridge’s ports
column.
Summary:
Core Features:
name immutable string (must be unique within
table)
ports set of Ports
mirrors set of Mirrors
netflow optional NetFlow
sflow optional sFlow
ipfix optional IPFIX
flood_vlans set of up to 4,096 integers, in range 0
to 4,095
auto_attach optional AutoAttach
OpenFlow Configuration:
controller set of Controllers
flow_tables map of integer-Flow_Table pairs, key in
range 0 to 254
fail_mode optional string, either secure or stand‐
alone
datapath_id optional string
datapath_version string
other_config : datapath-id optional string
other_config : dp-desc optional string
other_config : dp-sn optional string
other_config : disable-in-band
optional string, either true or false
other_config : in-band-queue
optional string, containing an integer,
in range 0 to 4,294,967,295
other_config : controller-queue-size
optional string, containing an integer,
in range 1 to 512
protocols set of strings, one of OpenFlow10, Open‐
Flow11, OpenFlow12, OpenFlow13, Open‐
Flow14, or OpenFlow15
Spanning Tree Configuration:
STP Configuration:
stp_enable boolean
other_config : stp-system-id
optional string
other_config : stp-priority
optional string, containing an integer,
in range 0 to 65,535
other_config : stp-hello-time
optional string, containing an integer,
in range 1 to 10
other_config : stp-max-age
optional string, containing an integer,
in range 6 to 40
other_config : stp-forward-delay
optional string, containing an integer,
in range 4 to 30
other_config : mcast-snooping-aging-time
optional string, containing an integer,
at least 1
other_config : mcast-snooping-table-size
optional string, containing an integer,
at least 1
other_config : mcast-snooping-disable-flood-unregistered
optional string, either true or false
STP Status:
status : stp_bridge_id optional string
status : stp_designated_root
optional string
status : stp_root_path_cost
optional string
Rapid Spanning Tree:
RSTP Configuration:
rstp_enable boolean
other_config : rstp-address
optional string
other_config : rstp-priority
optional string, containing an integer,
in range 0 to 61,440
other_config : rstp-ageing-time
optional string, containing an integer,
in range 10 to 1,000,000
other_config : rstp-force-protocol-version
optional string, containing an integer
other_config : rstp-max-age
optional string, containing an integer,
in range 6 to 40
other_config : rstp-forward-delay
optional string, containing an integer,
in range 4 to 30
other_config : rstp-transmit-hold-count
optional string, containing an integer,
in range 1 to 10
RSTP Status:
rstp_status : rstp_bridge_id
optional string
rstp_status : rstp_root_id
optional string
rstp_status : rstp_root_path_cost
optional string, containing an integer,
at least 0
rstp_status : rstp_designated_id
optional string
rstp_status : rstp_designated_port_id
optional string
rstp_status : rstp_bridge_port_id
optional string
Multicast Snooping Configuration:
mcast_snooping_enable boolean
Other Features:
datapath_type string
external_ids : bridge-id optional string
other_config : hwaddr optional string
other_config : forward-bpdu
optional string, either true or false
other_config : mac-aging-time
optional string, containing an integer,
at least 1
other_config : mac-table-size
optional string, containing an integer,
at least 1
Common Columns:
other_config map of string-string pairs
external_ids map of string-string pairs
Details:
Core Features:
name: immutable string (must be unique within table)
Bridge identifier. Must be unique among the names of ports, in‐
terfaces, and bridges on a host.
The name must be alphanumeric and must not contain forward or
backward slashes. The name of a bridge is also the name of an
Interface (and a Port) within the bridge, so the restrictions on
the name column in the Interface table, particularly on length,
also apply to bridge names. Refer to the documentation for In‐
terface names for details.
ports: set of Ports
Ports included in the bridge.
mirrors: set of Mirrors
Port mirroring configuration.
netflow: optional NetFlow
NetFlow configuration.
sflow: optional sFlow
sFlow(R) configuration.
ipfix: optional IPFIX
IPFIX configuration.
flood_vlans: set of up to 4,096 integers, in range 0 to 4,095
VLAN IDs of VLANs on which MAC address learning should be dis‐
abled, so that packets are flooded instead of being sent to spe‐
cific ports that are believed to contain packets’ destination
MACs. This should ordinarily be used to disable MAC learning on
VLANs used for mirroring (RSPAN VLANs). It may also be useful
for debugging.
SLB bonding (see the bond_mode column in the Port table) is in‐
compatible with flood_vlans. Consider using another bonding mode
or a different type of mirror instead.
auto_attach: optional AutoAttach
Auto Attach configuration.
OpenFlow Configuration:
controller: set of Controllers
OpenFlow controller set. If unset, then no OpenFlow controllers
will be used.
If there are primary controllers, removing all of them clears
the OpenFlow flow tables, group table, and meter table. If there
are no primary controllers, adding one also clears these tables.
Other changes to the set of controllers, such as adding or re‐
moving a service controller, adding another primary controller
to supplement an existing primary controller, or removing only
one of two primary controllers, have no effect on these tables.
flow_tables: map of integer-Flow_Table pairs, key in range 0 to 254
Configuration for OpenFlow tables. Each pair maps from an Open‐
Flow table ID to configuration for that table.
fail_mode: optional string, either secure or standalone
When a controller is configured, it is, ordinarily, responsible
for setting up all flows on the switch. Thus, if the connection
to the controller fails, no new network connections can be set
up. If the connection to the controller stays down long enough,
no packets can pass through the switch at all. This setting de‐
termines the switch’s response to such a situation. It may be
set to one of the following:
standalone
If no message is received from the controller for three
times the inactivity probe interval (see inactiv‐
ity_probe), then Open vSwitch will take over responsibil‐
ity for setting up flows. In this mode, Open vSwitch
causes the bridge to act like an ordinary MAC-learning
switch. Open vSwitch will continue to retry connecting to
the controller in the background and, when the connection
succeeds, it will discontinue its standalone behavior.
secure Open vSwitch will not set up flows on its own when the
controller connection fails or when no controllers are
defined. The bridge will continue to retry connecting to
any defined controllers forever.
The default is standalone if the value is unset, but future ver‐
sions of Open vSwitch may change the default.
The standalone mode can create forwarding loops on a bridge that
has more than one uplink port unless STP is enabled. To avoid
loops on such a bridge, configure secure mode or enable STP (see
stp_enable).
The fail_mode setting applies only to primary controllers. When
more than one primary controller is configured, fail_mode is
considered only when none of the configured controllers can be
contacted.
Changing fail_mode when no primary controllers are configured
clears the OpenFlow flow tables, group table, and meter table.
datapath_id: optional string
Reports the OpenFlow datapath ID in use. Exactly 16 hex digits.
(Setting this column has no useful effect. Set other-con‐
fig:datapath-id instead.)
datapath_version: string
Reports the datapath version. This column is maintained for
backwards compatibility. The preferred locatation is the data‐
path_id column of the Datapath table. The full documentation for
this column is there.
other_config : datapath-id: optional string
Overrides the default OpenFlow datapath ID, setting it to the
specified value specified in hex. The value must either have a
0x prefix or be exactly 16 hex digits long. May not be all-zero.
other_config : dp-desc: optional string
Human readable description of datapath. It is a maximum 256
byte-long free-form string to describe the datapath for debug‐
ging purposes, e.g. switch3 in room 3120. The value is returned
by the switch as a part of reply to OFPMP_DESC request
(ofp_desc). The OpenFlow specification (e.g. 1.3.5) describes
the ofp_desc structure to contaion "NULL terminated ASCII
strings". For the compatibility reasons no more than 255 ASCII
characters should be used.
other_config : dp-sn: optional string
Serial number. It is a maximum 32 byte-long free-form string to
provide an additional switch identification. The value is re‐
turned by the switch as a part of reply to OFPMP_DESC request
(ofp_desc). Same as mentioned in the description of other-con‐
fig:dp-desc, the string should be no more than 31 ASCII charac‐
ters for the compatibility.
other_config : disable-in-band: optional string, either true or false
If set to true, disable in-band control on the bridge regardless
of controller and manager settings.
other_config : in-band-queue: optional string, containing an integer,
in range 0 to 4,294,967,295
A queue ID as a nonnegative integer. This sets the OpenFlow
queue ID that will be used by flows set up by in-band control on
this bridge. If unset, or if the port used by an in-band control
flow does not have QoS configured, or if the port does not have
a queue with the specified ID, the default queue is used in‐
stead.
other_config : controller-queue-size: optional string, containing an
integer, in range 1 to 512
This sets the maximum size of the queue of packets that need to
be sent to the OpenFlow management controller. The value must be
less than 512. If not specified the queue size is limited to 100
packets by default. Note: increasing the queue size might have a
negative impact on latency.
protocols: set of strings, one of OpenFlow10, OpenFlow11, OpenFlow12,
OpenFlow13, OpenFlow14, or OpenFlow15
List of OpenFlow protocols that may be used when negotiating a
connection with a controller. OpenFlow 1.0, 1.1, 1.2, 1.3, 1.4,
and 1.5 are enabled by default if this column is empty.
Spanning Tree Configuration:
The IEEE 802.1D Spanning Tree Protocol (STP) is a network protocol that
ensures loop-free topologies. It allows redundant links to be included
in the network to provide automatic backup paths if the active links
fails.
These settings configure the slower-to-converge but still widely sup‐
ported version of Spanning Tree Protocol, sometimes known as
802.1D-1998. Open vSwitch also supports the newer Rapid Spanning Tree
Protocol (RSTP), documented later in the section titled Rapid Spanning
Tree Configuration.
STP Configuration:
stp_enable: boolean
Enable spanning tree on the bridge. By default, STP is disabled
on bridges. Bond, internal, and mirror ports are not supported
and will not participate in the spanning tree.
STP and RSTP are mutually exclusive. If both are enabled, RSTP
will be used.
other_config : stp-system-id: optional string
The bridge’s STP identifier (the lower 48 bits of the bridge-id)
in the form xx:xx:xx:xx:xx:xx. By default, the identifier is the
MAC address of the bridge.
other_config : stp-priority: optional string, containing an integer, in
range 0 to 65,535
The bridge’s relative priority value for determining the root
bridge (the upper 16 bits of the bridge-id). A bridge with the
lowest bridge-id is elected the root. By default, the priority
is 0x8000.
other_config : stp-hello-time: optional string, containing an integer,
in range 1 to 10
The interval between transmissions of hello messages by desig‐
nated ports, in seconds. By default the hello interval is 2 sec‐
onds.
other_config : stp-max-age: optional string, containing an integer, in
range 6 to 40
The maximum age of the information transmitted by the bridge
when it is the root bridge, in seconds. By default, the maximum
age is 20 seconds.
other_config : stp-forward-delay: optional string, containing an inte‐
ger, in range 4 to 30
The delay to wait between transitioning root and designated
ports to forwarding, in seconds. By default, the forwarding de‐
lay is 15 seconds.
other_config : mcast-snooping-aging-time: optional string, containing
an integer, at least 1
The maximum number of seconds to retain a multicast snooping en‐
try for which no packets have been seen. The default is cur‐
rently 300 seconds (5 minutes). The value, if specified, is
forced into a reasonable range, currently 15 to 3600 seconds.
other_config : mcast-snooping-table-size: optional string, containing
an integer, at least 1
The maximum number of multicast snooping addresses to learn. The
default is currently 2048. The value, if specified, is forced
into a reasonable range, currently 10 to 1,000,000.
other_config : mcast-snooping-disable-flood-unregistered: optional
string, either true or false
If set to false, unregistered multicast packets are forwarded to
all ports. If set to true, unregistered multicast packets are
forwarded to ports connected to multicast routers.
STP Status:
These key-value pairs report the status of 802.1D-1998. They are
present only if STP is enabled (via the stp_enable column).
status : stp_bridge_id: optional string
The bridge ID used in spanning tree advertisements, in the form
xxxx.yyyyyyyyyyyy where the xs are the STP priority, the ys are
the STP system ID, and each x and y is a hex digit.
status : stp_designated_root: optional string
The designated root for this spanning tree, in the same form as
status:stp_bridge_id. If this bridge is the root, this will have
the same value as status:stp_bridge_id, otherwise it will dif‐
fer.
status : stp_root_path_cost: optional string
The path cost of reaching the designated bridge. A lower number
is better. The value is 0 if this bridge is the root, otherwise
it is higher.
Rapid Spanning Tree:
Rapid Spanning Tree Protocol (RSTP), like STP, is a network protocol
that ensures loop-free topologies. RSTP superseded STP with the publi‐
cation of 802.1D-2004. Compared to STP, RSTP converges more quickly and
recovers more quickly from failures.
RSTP Configuration:
rstp_enable: boolean
Enable Rapid Spanning Tree on the bridge. By default, RSTP is
disabled on bridges. Bond, internal, and mirror ports are not
supported and will not participate in the spanning tree.
STP and RSTP are mutually exclusive. If both are enabled, RSTP
will be used.
other_config : rstp-address: optional string
The bridge’s RSTP address (the lower 48 bits of the bridge-id)
in the form xx:xx:xx:xx:xx:xx. By default, the address is the
MAC address of the bridge.
other_config : rstp-priority: optional string, containing an integer,
in range 0 to 61,440
The bridge’s relative priority value for determining the root
bridge (the upper 16 bits of the bridge-id). A bridge with the
lowest bridge-id is elected the root. By default, the priority
is 0x8000 (32768). This value needs to be a multiple of 4096,
otherwise it’s rounded to the nearest inferior one.
other_config : rstp-ageing-time: optional string, containing an inte‐
ger, in range 10 to 1,000,000
The Ageing Time parameter for the Bridge. The default value is
300 seconds.
other_config : rstp-force-protocol-version: optional string, containing
an integer
The Force Protocol Version parameter for the Bridge. This can
take the value 0 (STP Compatibility mode) or 2 (the default,
normal operation).
other_config : rstp-max-age: optional string, containing an integer, in
range 6 to 40
The maximum age of the information transmitted by the Bridge
when it is the Root Bridge. The default value is 20.
other_config : rstp-forward-delay: optional string, containing an inte‐
ger, in range 4 to 30
The delay used by STP Bridges to transition Root and Designated
Ports to Forwarding. The default value is 15.
other_config : rstp-transmit-hold-count: optional string, containing an
integer, in range 1 to 10
The Transmit Hold Count used by the Port Transmit state machine
to limit transmission rate. The default value is 6.
RSTP Status:
These key-value pairs report the status of 802.1D-2004. They are
present only if RSTP is enabled (via the rstp_enable column).
rstp_status : rstp_bridge_id: optional string
The bridge ID used in rapid spanning tree advertisements, in the
form x.yyy.zzzzzzzzzzzz where x is the RSTP priority, the ys are
a locally assigned system ID extension, the zs are the STP sys‐
tem ID, and each x, y, or z is a hex digit.
rstp_status : rstp_root_id: optional string
The root of this spanning tree, in the same form as rstp_sta‐
tus:rstp_bridge_id. If this bridge is the root, this will have
the same value as rstp_status:rstp_bridge_id, otherwise it will
differ.
rstp_status : rstp_root_path_cost: optional string, containing an inte‐
ger, at least 0
The path cost of reaching the root. A lower number is better.
The value is 0 if this bridge is the root, otherwise it is
higher.
rstp_status : rstp_designated_id: optional string
The RSTP designated ID, in the same form as rstp_sta‐
tus:rstp_bridge_id.
rstp_status : rstp_designated_port_id: optional string
The RSTP designated port ID, as a 4-digit hex number.
rstp_status : rstp_bridge_port_id: optional string
The RSTP bridge port ID, as a 4-digit hex number.
Multicast Snooping Configuration:
Multicast snooping (RFC 4541) monitors the Internet Group Management
Protocol (IGMP) and Multicast Listener Discovery traffic between hosts
and multicast routers. The switch uses what IGMP and MLD snooping
learns to forward multicast traffic only to interfaces that are con‐
nected to interested receivers. Currently it supports IGMPv1, IGMPv2,
IGMPv3, MLDv1 and MLDv2 protocols.
mcast_snooping_enable: boolean
Enable multicast snooping on the bridge. For now, the default is
disabled.
Other Features:
datapath_type: string
Name of datapath provider. The kernel datapath has type system.
The userspace datapath has type netdev. A manager may refer to
the datapath_types column of the Open_vSwitch table for a list
of the types accepted by this Open vSwitch instance.
external_ids : bridge-id: optional string
A unique identifier of the bridge.
other_config : hwaddr: optional string
An Ethernet address in the form xx:xx:xx:xx:xx:xx to set the
hardware address of the local port and influence the datapath
ID.
other_config : forward-bpdu: optional string, either true or false
Controls forwarding of BPDUs and other network control frames
when NORMAL action is invoked. When this option is false or un‐
set, frames with reserved Ethernet addresses (see table below)
will not be forwarded. When this option is true, such frames
will not be treated specially.
The above general rule has the following exceptions:
• If STP is enabled on the bridge (see the stp_enable col‐
umn in the Bridge table), the bridge processes all re‐
ceived STP packets and never passes them to OpenFlow or
forwards them. This is true even if STP is disabled on an
individual port.
• If LLDP is enabled on an interface (see the lldp column
in the Interface table), the interface processes received
LLDP packets and never passes them to OpenFlow or for‐
wards them.
Set this option to true if the Open vSwitch bridge connects dif‐
ferent Ethernet networks and is not configured to participate in
STP.
This option affects packets with the following destination MAC
addresses:
01:80:c2:00:00:00
IEEE 802.1D Spanning Tree Protocol (STP).
01:80:c2:00:00:01
IEEE Pause frame.
01:80:c2:00:00:0x
Other reserved protocols.
00:e0:2b:00:00:00
Extreme Discovery Protocol (EDP).
00:e0:2b:00:00:04 and 00:e0:2b:00:00:06
Ethernet Automatic Protection Switching (EAPS).
01:00:0c:cc:cc:cc
Cisco Discovery Protocol (CDP), VLAN Trunking Protocol
(VTP), Dynamic Trunking Protocol (DTP), Port Aggregation
Protocol (PAgP), and others.
01:00:0c:cc:cc:cd
Cisco Shared Spanning Tree Protocol PVSTP+.
01:00:0c:cd:cd:cd
Cisco STP Uplink Fast.
01:00:0c:00:00:00
Cisco Inter Switch Link.
01:00:0c:cc:cc:cx
Cisco CFM.
other_config : mac-aging-time: optional string, containing an integer,
at least 1
The maximum number of seconds to retain a MAC learning entry for
which no packets have been seen. The default is currently 300
seconds (5 minutes). The value, if specified, is forced into a
reasonable range, currently 15 to 3600 seconds.
A short MAC aging time allows a network to more quickly detect
that a host is no longer connected to a switch port. However, it
also makes it more likely that packets will be flooded unneces‐
sarily, when they are addressed to a connected host that rarely
transmits packets. To reduce the incidence of unnecessary flood‐
ing, use a MAC aging time longer than the maximum interval at
which a host will ordinarily transmit packets.
other_config : mac-table-size: optional string, containing an integer,
at least 1
The maximum number of MAC addresses to learn. The default is
currently 8192. The value, if specified, is forced into a rea‐
sonable range, currently 10 to 1,000,000.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
other_config: map of string-string pairs
external_ids: map of string-string pairs
Port TABLE
A port within a Bridge.
Most commonly, a port has exactly one ``interface,’’ pointed to by its
interfaces column. Such a port logically corresponds to a port on a
physical Ethernet switch. A port with more than one interface is a
``bonded port’’ (see Bonding Configuration).
Some properties that one might think as belonging to a port are actu‐
ally part of the port’s Interface members.
Summary:
name immutable string (must be unique within
table)
interfaces set of 1 or more Interfaces
VLAN Configuration:
vlan_mode optional string, one of access,
dot1q-tunnel, native-tagged, native-un‐
tagged, or trunk
tag optional integer, in range 0 to 4,095
trunks set of up to 4,096 integers, in range 0
to 4,095
cvlans set of up to 4,096 integers, in range 0
to 4,095
other_config : qinq-ethtype
optional string, either 802.1ad or 802.1q
other_config : priority-tags
optional string, one of always,
if-nonzero, or never
Bonding Configuration:
bond_mode optional string, one of active-backup,
balance-slb, or balance-tcp
other_config : bond-hash-basis
optional string, containing an integer
other_config : lb-output-action
optional string, either true or false
other_config : bond-primary
optional string
other_config : all-members-active
optional string, either true or false
Link Failure Detection:
other_config : bond-detect-mode
optional string, either carrier or miimon
other_config : bond-miimon-interval
optional string, containing an integer
bond_updelay integer
bond_downdelay integer
LACP Configuration:
lacp optional string, one of active, off, or
passive
other_config : lacp-system-id
optional string
other_config : lacp-system-priority
optional string, containing an integer,
in range 1 to 65,535
other_config : lacp-time optional string, either fast or slow
other_config : lacp-fallback-ab
optional string, either true or false
Rebalancing Configuration:
other_config : bond-rebalance-interval
optional string, containing an integer,
in range 0 to 2,147,483,647
bond_fake_iface boolean
Spanning Tree Protocol:
STP Configuration:
other_config : stp-enable
optional string, either true or false
other_config : stp-port-num
optional string, containing an integer,
in range 1 to 255
other_config : stp-port-priority
optional string, containing an integer,
in range 0 to 255
other_config : stp-path-cost
optional string, containing an integer,
in range 0 to 65,535
STP Status:
status : stp_port_id optional string
status : stp_state optional string, one of blocking, dis‐
abled, forwarding, learning, or listening
status : stp_sec_in_state
optional string, containing an integer,
at least 0
status : stp_role optional string, one of alternate, desig‐
nated, or root
Rapid Spanning Tree Protocol:
RSTP Configuration:
other_config : rstp-enable
optional string, either true or false
other_config : rstp-port-priority
optional string, containing an integer,
in range 0 to 240
other_config : rstp-port-num
optional string, containing an integer,
in range 1 to 4,095
other_config : rstp-path-cost
optional string, containing an integer
other_config : rstp-port-admin-edge
optional string, either true or false
other_config : rstp-port-auto-edge
optional string, either true or false
other_config : rstp-port-mcheck
optional string, either true or false
RSTP Status:
rstp_status : rstp_port_id
optional string
rstp_status : rstp_port_role
optional string, one of Alternate,
Backup, Designated, Disabled, or Root
rstp_status : rstp_port_state
optional string, one of Disabled, Dis‐
carding, Forwarding, or Learning
rstp_status : rstp_designated_bridge_id
optional string
rstp_status : rstp_designated_port_id
optional string
rstp_status : rstp_designated_path_cost
optional string, containing an integer
RSTP Statistics:
rstp_statistics : rstp_tx_count
optional integer
rstp_statistics : rstp_rx_count
optional integer
rstp_statistics : rstp_error_count
optional integer
rstp_statistics : rstp_uptime
optional integer
Multicast Snooping:
other_config : mcast-snooping-flood
optional string, either true or false
other_config : mcast-snooping-flood-reports
optional string, either true or false
Other Features:
qos optional QoS
mac optional string
fake_bridge boolean
protected boolean
external_ids : fake-bridge-*
optional string
other_config : transient optional string, either true or false
bond_active_slave optional string
Port Statistics:
Statistics: STP transmit and receive counters:
statistics : stp_tx_count
optional integer
statistics : stp_rx_count
optional integer
statistics : stp_error_count
optional integer
Common Columns:
other_config map of string-string pairs
external_ids map of string-string pairs
Details:
name: immutable string (must be unique within table)
Port name. For a non-bonded port, this should be the same as its
interface’s name. Port names must otherwise be unique among the
names of ports, interfaces, and bridges on a host. Because port
and interfaces names are usually the same, the restrictions on
the name column in the Interface table, particularly on length,
also apply to port names. Refer to the documentation for Inter‐
face names for details.
interfaces: set of 1 or more Interfaces
The port’s interfaces. If there is more than one, this is a
bonded Port.
VLAN Configuration:
In short, a VLAN (short for ``virtual LAN’’) is a way to partition a
single switch into multiple switches. VLANs can be confusing, so for an
introduction, please refer to the question ``What’s a VLAN?’’ in the
Open vSwitch FAQ.
A VLAN is sometimes encoded into a packet using a 802.1Q or 802.1ad
VLAN header, but every packet is part of some VLAN whether or not it is
encoded in the packet. (A packet that appears to have no VLAN is part
of VLAN 0, by default.) As a result, it’s useful to think of a VLAN as
a metadata property of a packet, separate from how the VLAN is encoded.
For a given port, this column determines how the encoding of a packet
that ingresses or egresses the port maps to the packet’s VLAN. When a
packet enters the switch, its VLAN is determined based on its setting
in this column and its VLAN headers, if any, and then, conceptually,
the VLAN headers are then stripped off. Conversely, when a packet exits
the switch, its VLAN and the settings in this column determine what
VLAN headers, if any, are pushed onto the packet before it egresses the
port.
The VLAN configuration in this column affects Open vSwitch only when it
is doing ``normal switching.’’ It does not affect flows set up by an
OpenFlow controller, outside of the OpenFlow ``normal action.’’
Bridge ports support the following types of VLAN configuration:
trunk A trunk port carries packets on one or more specified
VLANs specified in the trunks column (often, on every
VLAN). A packet that ingresses on a trunk port is in the
VLAN specified in its 802.1Q header, or VLAN 0 if the
packet has no 802.1Q header. A packet that egresses
through a trunk port will have an 802.1Q header if it has
a nonzero VLAN ID.
Any packet that ingresses on a trunk port tagged with a
VLAN that the port does not trunk is dropped.
access An access port carries packets on exactly one VLAN speci‐
fied in the tag column. Packets egressing on an access
port have no 802.1Q header.
Any packet with an 802.1Q header with a nonzero VLAN ID
that ingresses on an access port is dropped, regardless
of whether the VLAN ID in the header is the access port’s
VLAN ID.
native-tagged
A native-tagged port resembles a trunk port, with the ex‐
ception that a packet without an 802.1Q header that in‐
gresses on a native-tagged port is in the ``native VLAN’’
(specified in the tag column).
native-untagged
A native-untagged port resembles a native-tagged port,
with the exception that a packet that egresses on a na‐
tive-untagged port in the native VLAN will not have an
802.1Q header.
dot1q-tunnel
A dot1q-tunnel port is somewhat like an access port. Like
an access port, it carries packets on the single VLAN
specified in the tag column and this VLAN, called the
service VLAN, does not appear in an 802.1Q header for
packets that ingress or egress on the port. The main dif‐
ference lies in the behavior when packets that include a
802.1Q header ingress on the port. Whereas an access port
drops such packets, a dot1q-tunnel port treats these as
double-tagged with the outer service VLAN tag and the in‐
ner customer VLAN taken from the 802.1Q header. Corre‐
spondingly, to egress on the port, a packet outer VLAN
(or only VLAN) must be tag, which is removed before
egress, which exposes the inner (customer) VLAN if one is
present.
If cvlans is set, only allows packets in the specified
customer VLANs.
A packet will only egress through bridge ports that carry the VLAN of
the packet, as described by the rules above.
vlan_mode: optional string, one of access, dot1q-tunnel, native-tagged,
native-untagged, or trunk
The VLAN mode of the port, as described above. When this column
is empty, a default mode is selected as follows:
• If tag contains a value, the port is an access port. The
trunks column should be empty.
• Otherwise, the port is a trunk port. The trunks column
value is honored if it is present.
tag: optional integer, in range 0 to 4,095
For an access port, the port’s implicitly tagged VLAN. For a na‐
tive-tagged or native-untagged port, the port’s native VLAN.
Must be empty if this is a trunk port.
trunks: set of up to 4,096 integers, in range 0 to 4,095
For a trunk, native-tagged, or native-untagged port, the 802.1Q
VLAN or VLANs that this port trunks; if it is empty, then the
port trunks all VLANs. Must be empty if this is an access port.
A native-tagged or native-untagged port always trunks its native
VLAN, regardless of whether trunks includes that VLAN.
cvlans: set of up to 4,096 integers, in range 0 to 4,095
For a dot1q-tunnel port, the customer VLANs that this port in‐
cludes. If this is empty, the port includes all customer VLANs.
For other kinds of ports, this setting is ignored.
other_config : qinq-ethtype: optional string, either 802.1ad or 802.1q
For a dot1q-tunnel port, this is the TPID for the service tag,
that is, for the 802.1Q header that contains the service VLAN
ID. Because packets that actually ingress and egress a dot1q-
tunnel port do not include an 802.1Q header for the service
VLAN, this does not affect packets on the dot1q-tunnel port it‐
self. Rather, it determines the service VLAN for a packet that
ingresses on a dot1q-tunnel port and egresses on a trunk port.
The value 802.1ad specifies TPID 0x88a8, which is also the de‐
fault if the setting is omitted. The value 802.1q specifies TPID
0x8100.
For other kinds of ports, this setting is ignored.
other_config : priority-tags: optional string, one of always,
if-nonzero, or never
An 802.1Q header contains two important pieces of information: a
VLAN ID and a priority. A frame with a zero VLAN ID, called a
``priority-tagged’’ frame, is supposed to be treated the same
way as a frame without an 802.1Q header at all (except for the
priority).
However, some network elements ignore any frame that has 802.1Q
header at all, even when the VLAN ID is zero. Therefore, by de‐
fault Open vSwitch does not output priority-tagged frames, in‐
stead omitting the 802.1Q header entirely if the VLAN ID is
zero. Set this key to if-nonzero to enable priority-tagged
frames on a port.
For if-nonzero Open vSwitch omits the 802.1Q header on output if
both the VLAN ID and priority would be zero. Set to always to
retain the 802.1Q header in such frames as well.
All frames output to native-tagged ports have a nonzero VLAN ID,
so this setting is not meaningful on native-tagged ports.
Bonding Configuration:
A port that has more than one interface is a ``bonded port.’’ Bonding
allows for load balancing and fail-over.
The following types of bonding will work with any kind of upstream
switch. On the upstream switch, do not configure the interfaces as a
bond:
balance-slb
Balances flows among members based on source MAC address
and output VLAN, with periodic rebalancing as traffic
patterns change.
active-backup
Assigns all flows to one member, failing over to a backup
member when the active member is disabled. This is the
only bonding mode in which interfaces may be plugged into
different upstream switches.
The following modes require the upstream switch to support 802.3ad with
successful LACP negotiation. If LACP negotiation fails and other-con‐
fig:lacp-fallback-ab is true, then active-backup mode is used:
balance-tcp
Balances flows among members based on L3 and L4 protocol
information such as IP addresses and TCP/UDP ports.
These columns apply only to bonded ports. Their values are otherwise
ignored.
bond_mode: optional string, one of active-backup, balance-slb, or bal‐
ance-tcp
The type of bonding used for a bonded port. Defaults to ac‐
tive-backup if unset.
other_config : bond-hash-basis: optional string, containing an integer
An integer hashed along with flows when choosing output members
in load balanced bonds. When changed, all flows will be assigned
different hash values possibly causing member selection deci‐
sions to change. Does not affect bonding modes which do not em‐
ploy load balancing such as active-backup.
other_config : lb-output-action: optional string, either true or false
Enable/disable usage of optimized lb_output action for balancing
flows among output members in load balanced bonds in bal‐
ance-tcp. When enabled, it uses optimized path for balance-tcp
mode by using rss hash and avoids recirculation. This knob does
not affect other balancing modes.
other_config : bond-primary: optional string
If a member interface with this name exists in the bond and is
up, it will be made active. Relevant only when other_con‐
fig:bond_mode is active-backup or if balance-tcp falls back to
active-backup (e.g., LACP negotiation fails and other_con‐
fig:lacp-fallback-ab is true).
other_config : all-members-active: optional string, either true or
false
Enable/Disable delivery of broadcast/multicast packets on sec‐
ondary interface of a balance-slb bond. Relevant only when lacp
is off.
This parameter is identical to all_slaves_active for Linux ker‐
nel bonds. Disabled by default as it is not a desirable configu‐
ration for most users.
Link Failure Detection:
An important part of link bonding is detecting that links are down so
that they may be disabled. These settings determine how Open vSwitch
detects link failure.
other_config : bond-detect-mode: optional string, either carrier or mi‐
imon
The means used to detect link failures. Defaults to carrier
which uses each interface’s carrier to detect failures. When set
to miimon, will check for failures by polling each interface’s
MII.
other_config : bond-miimon-interval: optional string, containing an in‐
teger
The interval, in milliseconds, between successive attempts to
poll each interface’s MII. Relevant only when other_config:bond-
detect-mode is miimon.
bond_updelay: integer
The number of milliseconds for which the link must stay up on an
interface before the interface is considered to be up. Specify 0
to enable the interface immediately.
This setting is honored only when at least one bonded interface
is already enabled. When no interfaces are enabled, then the
first bond interface to come up is enabled immediately.
bond_downdelay: integer
The number of milliseconds for which the link must stay down on
an interface before the interface is considered to be down.
Specify 0 to disable the interface immediately.
LACP Configuration:
LACP, the Link Aggregation Control Protocol, is an IEEE standard that
allows switches to automatically detect that they are connected by mul‐
tiple links and aggregate across those links. These settings control
LACP behavior.
lacp: optional string, one of active, off, or passive
Configures LACP on this port. LACP allows directly connected
switches to negotiate which links may be bonded. LACP may be en‐
abled on non-bonded ports for the benefit of any switches they
may be connected to. active ports are allowed to initiate LACP
negotiations. passive ports are allowed to participate in LACP
negotiations initiated by a remote switch, but not allowed to
initiate such negotiations themselves. If LACP is enabled on a
port whose partner switch does not support LACP, the bond will
be disabled, unless other-config:lacp-fallback-ab is set to
true. Defaults to off if unset.
other_config : lacp-system-id: optional string
The LACP system ID of this Port. The system ID of a LACP bond is
used to identify itself to its partners. Must be a nonzero MAC
address. Defaults to the bridge Ethernet address if unset.
other_config : lacp-system-priority: optional string, containing an in‐
teger, in range 1 to 65,535
The LACP system priority of this Port. In LACP negotiations,
link status decisions are made by the system with the numeri‐
cally lower priority.
other_config : lacp-time: optional string, either fast or slow
The LACP timing which should be used on this Port. By default
slow is used. When configured to be fast LACP heartbeats are re‐
quested at a rate of once per second causing connectivity prob‐
lems to be detected more quickly. In slow mode, heartbeats are
requested at a rate of once every 30 seconds.
other_config : lacp-fallback-ab: optional string, either true or false
Determines the behavior of openvswitch bond in LACP mode. If the
partner switch does not support LACP, setting this option to
true allows openvswitch to fallback to active-backup. If the op‐
tion is set to false, the bond will be disabled. In both the
cases, once the partner switch is configured to LACP mode, the
bond will use LACP.
Rebalancing Configuration:
These settings control behavior when a bond is in balance-slb or bal‐
ance-tcp mode.
other_config : bond-rebalance-interval: optional string, containing an
integer, in range 0 to 2,147,483,647
For a load balanced bonded port, the number of milliseconds be‐
tween successive attempts to rebalance the bond, that is, to
move flows from one interface on the bond to another in an at‐
tempt to keep usage of each interface roughly equal. If zero,
load balancing is disabled on the bond (link failure still cause
flows to move). If less than 1000ms, the rebalance interval will
be 1000ms.
bond_fake_iface: boolean
For a bonded port, whether to create a fake internal interface
with the name of the port. Use only for compatibility with
legacy software that requires this.
Spanning Tree Protocol:
The configuration here is only meaningful, and the status is only popu‐
lated, when 802.1D-1998 Spanning Tree Protocol is enabled on the port’s
Bridge with its stp_enable column.
STP Configuration:
other_config : stp-enable: optional string, either true or false
When STP is enabled on a bridge, it is enabled by default on all
of the bridge’s ports except bond, internal, and mirror ports
(which do not work with STP). If this column’s value is false,
STP is disabled on the port.
other_config : stp-port-num: optional string, containing an integer, in
range 1 to 255
The port number used for the lower 8 bits of the port-id. By de‐
fault, the numbers will be assigned automatically. If any port’s
number is manually configured on a bridge, then they must all
be.
other_config : stp-port-priority: optional string, containing an inte‐
ger, in range 0 to 255
The port’s relative priority value for determining the root port
(the upper 8 bits of the port-id). A port with a lower port-id
will be chosen as the root port. By default, the priority is
0x80.
other_config : stp-path-cost: optional string, containing an integer,
in range 0 to 65,535
Spanning tree path cost for the port. A lower number indicates a
faster link. By default, the cost is based on the maximum speed
of the link.
STP Status:
status : stp_port_id: optional string
The port ID used in spanning tree advertisements for this port,
as 4 hex digits. Configuring the port ID is described in the
stp-port-num and stp-port-priority keys of the other_config sec‐
tion earlier.
status : stp_state: optional string, one of blocking, disabled, for‐
warding, learning, or listening
STP state of the port.
status : stp_sec_in_state: optional string, containing an integer, at
least 0
The amount of time this port has been in the current STP state,
in seconds.
status : stp_role: optional string, one of alternate, designated, or
root
STP role of the port.
Rapid Spanning Tree Protocol:
The configuration here is only meaningful, and the status and statis‐
tics are only populated, when 802.1D-1998 Spanning Tree Protocol is en‐
abled on the port’s Bridge with its stp_enable column.
RSTP Configuration:
other_config : rstp-enable: optional string, either true or false
When RSTP is enabled on a bridge, it is enabled by default on
all of the bridge’s ports except bond, internal, and mirror
ports (which do not work with RSTP). If this column’s value is
false, RSTP is disabled on the port.
other_config : rstp-port-priority: optional string, containing an inte‐
ger, in range 0 to 240
The port’s relative priority value for determining the root
port, in multiples of 16. By default, the port priority is 0x80
(128). Any value in the lower 4 bits is rounded off. The signif‐
icant upper 4 bits become the upper 4 bits of the port-id. A
port with the lowest port-id is elected as the root.
other_config : rstp-port-num: optional string, containing an integer,
in range 1 to 4,095
The local RSTP port number, used as the lower 12 bits of the
port-id. By default the port numbers are assigned automatically,
and typically may not correspond to the OpenFlow port numbers. A
port with the lowest port-id is elected as the root.
other_config : rstp-path-cost: optional string, containing an integer
The port path cost. The Port’s contribution, when it is the Root
Port, to the Root Path Cost for the Bridge. By default the cost
is automatically calculated from the port’s speed.
other_config : rstp-port-admin-edge: optional string, either true or
false
The admin edge port parameter for the Port. Default is false.
other_config : rstp-port-auto-edge: optional string, either true or
false
The auto edge port parameter for the Port. Default is true.
other_config : rstp-port-mcheck: optional string, either true or false
The mcheck port parameter for the Port. Default is false. May be
set to force the Port Protocol Migration state machine to trans‐
mit RST BPDUs for a MigrateTime period, to test whether all STP
Bridges on the attached LAN have been removed and the Port can
continue to transmit RSTP BPDUs. Setting mcheck has no effect if
the Bridge is operating in STP Compatibility mode.
Changing the value from true to false has no effect, but needs
to be done if this behavior is to be triggered again by subse‐
quently changing the value from false to true.
RSTP Status:
rstp_status : rstp_port_id: optional string
The port ID used in spanning tree advertisements for this port,
as 4 hex digits. Configuring the port ID is described in the
rstp-port-num and rstp-port-priority keys of the other_config
section earlier.
rstp_status : rstp_port_role: optional string, one of Alternate,
Backup, Designated, Disabled, or Root
RSTP role of the port.
rstp_status : rstp_port_state: optional string, one of Disabled, Dis‐
carding, Forwarding, or Learning
RSTP state of the port.
rstp_status : rstp_designated_bridge_id: optional string
The port’s RSTP designated bridge ID, in the same form as
rstp_status:rstp_bridge_id in the Bridge table.
rstp_status : rstp_designated_port_id: optional string
The port’s RSTP designated port ID, as 4 hex digits.
rstp_status : rstp_designated_path_cost: optional string, containing an
integer
The port’s RSTP designated path cost. Lower is better.
RSTP Statistics:
rstp_statistics : rstp_tx_count: optional integer
Number of RSTP BPDUs transmitted through this port.
rstp_statistics : rstp_rx_count: optional integer
Number of valid RSTP BPDUs received by this port.
rstp_statistics : rstp_error_count: optional integer
Number of invalid RSTP BPDUs received by this port.
rstp_statistics : rstp_uptime: optional integer
The duration covered by the other RSTP statistics, in seconds.
Multicast Snooping:
other_config : mcast-snooping-flood: optional string, either true or
false
If set to true, multicast packets (except Reports) are uncondi‐
tionally forwarded to the specific port.
other_config : mcast-snooping-flood-reports: optional string, either
true or false
If set to true, multicast Reports are unconditionally forwarded
to the specific port.
Other Features:
qos: optional QoS
Quality of Service configuration for this port.
mac: optional string
The MAC address to use for this port for the purpose of choosing
the bridge’s MAC address. This column does not necessarily re‐
flect the port’s actual MAC address, nor will setting it change
the port’s actual MAC address.
fake_bridge: boolean
Does this port represent a sub-bridge for its tagged VLAN within
the Bridge? See ovs-vsctl(8) for more information.
protected: boolean
The protected ports feature allows certain ports to be desig‐
nated as protected. Traffic between protected ports is blocked.
Protected ports can send traffic to unprotected ports. Unpro‐
tected ports can send traffic to any port. Default is false.
external_ids : fake-bridge-*: optional string
External IDs for a fake bridge (see the fake_bridge column) are
defined by prefixing a Bridge external_ids key with
fake-bridge-, e.g. fake-bridge-bridge-id.
other_config : transient: optional string, either true or false
If set to true, the port will be removed when ovs-ctl start
--delete-transient-ports is used.
bond_active_slave: optional string
For a bonded port, record the MAC address of the current active
member.
Port Statistics:
Key-value pairs that report port statistics. The update period is con‐
trolled by other_config:stats-update-interval in the Open_vSwitch ta‐
ble.
Statistics: STP transmit and receive counters:
statistics : stp_tx_count: optional integer
Number of STP BPDUs sent on this port by the spanning tree li‐
brary.
statistics : stp_rx_count: optional integer
Number of STP BPDUs received on this port and accepted by the
spanning tree library.
statistics : stp_error_count: optional integer
Number of bad STP BPDUs received on this port. Bad BPDUs include
runt packets and those with an unexpected protocol ID.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
other_config: map of string-string pairs
external_ids: map of string-string pairs
Interface TABLE
An interface within a Port.
Summary:
Core Features:
name immutable string (must be unique within
table)
ifindex optional integer, in range 0 to
4,294,967,295
mac_in_use optional string
mac optional string
error optional string
OpenFlow Port Number:
ofport optional integer
ofport_request optional integer, in range 1 to 65,279
System-Specific Details:
type string
Tunnel Options:
options : remote_ip optional string
options : local_ip optional string
options : in_key optional string
options : out_key optional string
options : dst_port optional string
options : key optional string
options : tos optional string
options : ttl optional string
options : df_default optional string, either true or false
options : egress_pkt_mark optional string
Tunnel Options: lisp only:
options : packet_type optional string, either legacy_l3 or ptap
Tunnel Options: vxlan only:
options : exts optional string
options : packet_type optional string, one of legacy_l2,
legacy_l3, or ptap
Tunnel Options: gre only:
options : packet_type optional string, one of legacy_l2,
legacy_l3, or ptap
options : seq optional string, either true or false
Tunnel Options: gre, ip6gre, geneve, bareudp and vxlan:
options : csum optional string, either true or false
Tunnel Options: IPsec:
options : psk optional string
options : remote_cert optional string
options : remote_name optional string
Tunnel Options: erspan only:
options : erspan_idx optional string
options : erspan_ver optional string
options : erspan_dir optional string
options : erspan_hwid optional string
Tunnel Options: Bareudp only:
options : payload_type optional string
Tunnel Options: srv6 only:
options : srv6_segs optional string
options : srv6_flowlabel optional string, one of compute, copy, or
zero
Patch Options:
options : peer optional string
PMD (Poll Mode Driver) Options:
options : n_rxq optional string, containing an integer,
at least 1
options : dpdk-devargs optional string
other_config : pmd-rxq-affinity
optional string
options : xdp-mode optional string, one of best-effort,
generic, native-with-zerocopy, or native
options : use-need-wakeup optional string, either true or false
options : vhost-server-path
optional string
options : tx-retries-max optional string, containing an integer,
in range 0 to 32
options : n_rxq_desc optional string, containing an integer,
in range 1 to 4,096
options : n_txq_desc optional string, containing an integer,
in range 1 to 4,096
options : dpdk-vf-mac optional string
options : rx-steering optional string, either rss+lacp or rss
other_config : tx-steering optional string, either hash or thread
EMC (Exact Match Cache) Configuration:
other_config : emc-enable optional string, either true or false
MTU:
mtu optional integer
mtu_request optional integer, at least 1
Interface Status:
admin_state optional string, either down or up
link_state optional string, either down or up
link_resets optional integer
link_speed optional integer
duplex optional string, either full or half
lacp_current optional boolean
status map of string-string pairs
status : driver_name optional string
status : driver_version optional string
status : firmware_version optional string
status : source_ip optional string
status : tunnel_egress_iface
optional string
status : tunnel_egress_iface_carrier
optional string, either down or up
dpdk:
status : port_no optional string
status : numa_id optional string
status : min_rx_bufsize optional string
status : max_rx_pktlen optional string
status : max_rx_queues optional string
status : max_tx_queues optional string
status : max_mac_addrs optional string
status : max_hash_mac_addrs
optional string
status : max_vfs optional string
status : max_vmdq_pools optional string
status : n_rxq optional string
status : n_txq optional string
status : rx_csum_offload optional string
status : if_type optional string
status : if_descr optional string
status : bus_info optional string
status : dpdk-vf-mac optional string
status : rx-steering optional string
status : rx_steering_queue
optional string
status : rss_queues optional string
dpdkvhostuser:
status : mode optional string
status : features optional string
status : num_of_vrings optional string
status : numa optional string
status : socket optional string
status : status optional string
status : vring_n_size optional string
status : userspace-tso optional string
afxdp:
status : xdp-mode optional string
Statistics:
Statistics: Successful transmit and receive counters:
statistics : rx_packets optional integer
statistics : rx_bytes optional integer
statistics : tx_packets optional integer
statistics : tx_bytes optional integer
Statistics: Receive errors:
statistics : rx_dropped optional integer
statistics : rx_frame_err
optional integer
statistics : rx_over_err optional integer
statistics : rx_crc_err optional integer
statistics : rx_errors optional integer
Statistics: Transmit errors:
statistics : tx_dropped optional integer
statistics : collisions optional integer
statistics : tx_errors optional integer
Ingress Policing:
ingress_policing_rate integer, at least 0
ingress_policing_kpkts_rate
integer, at least 0
ingress_policing_burst integer, at least 0
ingress_policing_kpkts_burst
integer, at least 0
Bidirectional Forwarding Detection (BFD):
BFD Configuration:
bfd : enable optional string, either true or false
bfd : min_rx optional string, containing an integer,
at least 1
bfd : min_tx optional string, containing an integer,
at least 1
bfd : decay_min_rx optional string, containing an integer
bfd : forwarding_if_rx optional string, either true or false
bfd : cpath_down optional string, either true or false
bfd : check_tnl_key optional string, either true or false
bfd : bfd_local_src_mac optional string
bfd : bfd_local_dst_mac optional string
bfd : bfd_remote_dst_mac optional string
bfd : bfd_src_ip optional string
bfd : bfd_dst_ip optional string
bfd : oam optional string
bfd : mult optional string, containing an integer,
in range 1 to 255
BFD Status:
bfd_status : state optional string, one of admin_down, down,
init, or up
bfd_status : forwarding optional string, either true or false
bfd_status : diagnostic optional string
bfd_status : remote_state
optional string, one of admin_down, down,
init, or up
bfd_status : remote_diagnostic
optional string
bfd_status : flap_count optional string, containing an integer,
at least 0
Connectivity Fault Management:
cfm_mpid optional integer
cfm_flap_count optional integer
cfm_fault optional boolean
cfm_fault_status : recv none
cfm_fault_status : rdi none
cfm_fault_status : maid none
cfm_fault_status : loopback
none
cfm_fault_status : overflow
none
cfm_fault_status : override
none
cfm_fault_status : interval
none
cfm_remote_opstate optional string, either down or up
cfm_health optional integer, in range 0 to 100
cfm_remote_mpids set of integers
other_config : cfm_interval
optional string, containing an integer
other_config : cfm_extended
optional string, either true or false
other_config : cfm_demand optional string, either true or false
other_config : cfm_opstate optional string, either down or up
other_config : cfm_ccm_vlan
optional string, containing an integer,
in range 1 to 4,095
other_config : cfm_ccm_pcp optional string, containing an integer,
in range 1 to 7
Bonding Configuration:
other_config : lacp-port-id
optional string, containing an integer,
in range 1 to 65,535
other_config : lacp-port-priority
optional string, containing an integer,
in range 1 to 65,535
other_config : lacp-aggregation-key
optional string, containing an integer,
in range 1 to 65,535
Virtual Machine Identifiers:
external_ids : attached-mac
optional string
external_ids : iface-id optional string
external_ids : iface-status
optional string, either active or inac‐
tive
external_ids : vm-id optional string
Auto Attach Configuration:
lldp : enable optional string, either true or false
Flow control Configuration:
options : rx-flow-ctrl optional string, either true or false
options : tx-flow-ctrl optional string, either true or false
options : flow-ctrl-autoneg
optional string, either true or false
Link State Change detection mode:
options : dpdk-lsc-interrupt
optional string, either true or false
Common Columns:
other_config map of string-string pairs
external_ids map of string-string pairs
Details:
Core Features:
name: immutable string (must be unique within table)
Interface name. Should be alphanumeric. For non-bonded port,
this should be the same as the port name. It must otherwise be
unique among the names of ports, interfaces, and bridges on a
host.
The maximum length of an interface name depends on the underly‐
ing datapath:
• The names of interfaces implemented as Linux and BSD net‐
work devices, including interfaces with type internal,
tap, or system plus the different types of tunnel ports,
are limited to 15 bytes. Windows limits these names to
255 bytes.
• The names of patch ports are not used in the underlying
datapath, so operating system restrictions do not apply.
Thus, they may have arbitrary length.
Regardless of other restrictions, OpenFlow only supports 15-byte
names, which means that ovs-ofctl and OpenFlow controllers will
show names truncated to 15 bytes.
ifindex: optional integer, in range 0 to 4,294,967,295
A positive interface index as defined for SNMP MIB-II in RFCs
1213 and 2863, if the interface has one, otherwise 0. The
ifindex is useful for seamless integration with protocols such
as SNMP and sFlow.
mac_in_use: optional string
The MAC address in use by this interface.
mac: optional string
Ethernet address to set for this interface. If unset then the
default MAC address is used:
• For the local interface, the default is the lowest-num‐
bered MAC address among the other bridge ports, either
the value of the mac in its Port record, if set, or its
actual MAC (for bonded ports, the MAC of its member whose
name is first in alphabetical order). Internal ports and
bridge ports that are used as port mirroring destinations
(see the Mirror table) are ignored.
• For other internal interfaces, the default MAC is ran‐
domly generated.
• External interfaces typically have a MAC address associ‐
ated with their hardware.
Some interfaces may not have a software-controllable MAC ad‐
dress. This option only affects internal ports. For other type
ports, you can change the MAC address outside Open vSwitch, us‐
ing ip command.
error: optional string
If the configuration of the port failed, as indicated by -1 in
ofport, Open vSwitch sets this column to an error description in
human readable form. Otherwise, Open vSwitch clears this column.
OpenFlow Port Number:
When a client adds a new interface, Open vSwitch chooses an OpenFlow
port number for the new port. If the client that adds the port fills in
ofport_request, then Open vSwitch tries to use its value as the Open‐
Flow port number. Otherwise, or if the requested port number is already
in use or cannot be used for another reason, Open vSwitch automatically
assigns a free port number. Regardless of how the port number was ob‐
tained, Open vSwitch then reports in ofport the port number actually
assigned.
Open vSwitch limits the port numbers that it automatically assigns to
the range 1 through 32,767, inclusive. Controllers therefore have free
use of ports 32,768 and up.
ofport: optional integer
OpenFlow port number for this interface. Open vSwitch sets this
column’s value, so other clients should treat it as read-only.
The OpenFlow ``local’’ port (OFPP_LOCAL) is 65,534. The other
valid port numbers are in the range 1 to 65,279, inclusive.
Value -1 indicates an error adding the interface.
ofport_request: optional integer, in range 1 to 65,279
Requested OpenFlow port number for this interface.
A client should ideally set this column’s value in the same
database transaction that it uses to create the interface. Open
vSwitch version 2.1 and later will honor a later request for a
specific port number, althuogh it might confuse some con‐
trollers: OpenFlow does not have a way to announce a port number
change, so Open vSwitch represents it over OpenFlow as a port
deletion followed immediately by a port addition.
If ofport_request is set or changed to some other port’s auto‐
matically assigned port number, Open vSwitch chooses a new port
number for the latter port.
System-Specific Details:
type: string
The interface type. The types supported by a particular instance
of Open vSwitch are listed in the iface_types column in the
Open_vSwitch table. The following types are defined:
system An ordinary network device, e.g. eth0 on Linux. Sometimes
referred to as ``external interfaces’’ since they are
generally connected to hardware external to that on which
the Open vSwitch is running. The empty string is a syn‐
onym for system.
internal
A simulated network device that sends and receives traf‐
fic. An internal interface whose name is the same as its
bridge’s name is called the ``local interface.’’ It does
not make sense to bond an internal interface, so the
terms ``port’’ and ``interface’’ are often used impre‐
cisely for internal interfaces.
tap A TUN/TAP device managed by Open vSwitch.
Open vSwitch checks the interface state before send pack‐
ets to the device. When it is down, the packets are
dropped and the tx_dropped statistic is updated accord‐
ingly. Older versions of Open vSwitch did not check the
interface state and then the tx_packets was incremented
along with tx_dropped.
geneve An Ethernet over Geneve
(http://tools.ietf.org/html/draft-ietf-nvo3-geneve)
IPv4/IPv6 tunnel. A description of how to match and set
Geneve options can be found in the ovs-ofctl manual page.
gre Generic Routing Encapsulation (GRE) over IPv4 tunnel,
configurable to encapsulate layer 2 or layer 3 traffic.
ip6gre Generic Routing Encapsulation (GRE) over IPv6 tunnel, en‐
capsulate layer 2 traffic.
vxlan An Ethernet tunnel over the UDP-based VXLAN protocol de‐
scribed in RFC 7348.
Open vSwitch uses IANA-assigned UDP destination port
4789. The source port used for VXLAN traffic varies on a
per-flow basis and is in the ephemeral port range.
lisp A layer 3 tunnel over the experimental, UDP-based Loca‐
tor/ID Separation Protocol (RFC 6830).
Only IPv4 and IPv6 packets are supported by the protocol,
and they are sent and received without an Ethernet
header. Traffic to/from LISP ports is expected to be con‐
figured explicitly, and the ports are not intended to
participate in learning based switching. As such, they
are always excluded from packet flooding.
stt The Stateless TCP Tunnel (STT) is particularly useful
when tunnel endpoints are in end-systems, as it utilizes
the capabilities of standard network interface cards to
improve performance. STT utilizes a TCP-like header in‐
side the IP header. It is stateless, i.e., there is no
TCP connection state of any kind associated with the tun‐
nel. The TCP-like header is used to leverage the capabil‐
ities of existing network interface cards, but should not
be interpreted as implying any sort of connection state
between endpoints. Since the STT protocol does not engage
in the usual TCP 3-way handshake, so it will have diffi‐
culty traversing stateful firewalls. The protocol is doc‐
umented at https://tools.ietf.org/html/draft-davie-stt
All traffic uses a default destination port of 7471.
patch A pair of virtual devices that act as a patch cable.
gtpu GPRS Tunneling Protocol (GTP) is a group of IP-based com‐
munications protocols used to carry general packet radio
service (GPRS) within GSM, UMTS and LTE networks. GTP-U
is used for carrying user data within the GPRS core net‐
work and between the radio access network and the core
network. The user data transported can be packets in any
of IPv4, IPv6, or PPP formats.
The protocol is documented at http://www.3gpp.org/DynaRe‐
port/29281.htm
Open vSwitch uses UDP destination port 2152. The source
port used for GTP traffic varies on a per-flow basis and
is in the ephemeral port range.
Bareudp
The Bareudp tunnel provides a generic L3 encapsulation
support for tunnelling different L3 protocols like MPLS,
IP, NSH etc. inside a UDP tunnel.
srv6 Segment Routing IPv6 (SRv6) tunnel encapsulates L3 traf‐
fic as "IPv6 in IPv6" or "IPv4 in IPv6" with Segment
Routing Header (SRH) defined in RFC 8754. The segment
list in SRH can be set using a SRv6 specific option.
Tunnel Options:
These options apply to interfaces with type of geneve, bareudp, gre,
ip6gre, vxlan, lisp, stt and srv6.
Each tunnel must be uniquely identified by the combination of type, op‐
tions:remote_ip, options:local_ip, and options:in_key. If two ports are
defined that are the same except one has an optional identifier and the
other does not, the more specific one is matched first. options:in_key
is considered more specific than options:local_ip if a port defines one
and another port defines the other. options:in_key is not applicable
for bareudp and srv6 tunnels. Hence it is not considered while identi‐
fying bareudp or srv6 tunnels.
options : remote_ip: optional string
Required. The remote tunnel endpoint, one of:
• An IPv4 or IPv6 address (not a DNS name), e.g.
192.168.0.123. Only unicast endpoints are supported.
• The word flow. The tunnel accepts packets from any remote
tunnel endpoint. To process only packets from a specific
remote tunnel endpoint, the flow entries may match on the
tun_src or tun_ipv6_srcfield. When sending packets to a
remote_ip=flow tunnel, the flow actions must explicitly
set the tun_dst or tun_ipv6_dst field to the IP address
of the desired remote tunnel endpoint, e.g. with a
set_field action.
The remote tunnel endpoint for any packet received from a tunnel
is available in the tun_src field for matching in the flow ta‐
ble.
options : local_ip: optional string
Optional. The tunnel destination IP that received packets must
match. Default is to match all addresses. If specified, may be
one of:
• An IPv4/IPv6 address (not a DNS name), e.g. 192.168.12.3.
• The word flow. The tunnel accepts packets sent to any of
the local IP addresses of the system running OVS. To
process only packets sent to a specific IP address, the
flow entries may match on the tun_dst or tun_ipv6_dst
field. When sending packets to a local_ip=flow tunnel,
the flow actions may explicitly set the tun_src or
tun_ipv6_src field to the desired IP address, e.g. with a
set_field action. However, while routing the tunneled
packet out, the local system may override the specified
address with the local IP address configured for the out‐
going system interface.
This option is valid only for tunnels also configured
with the remote_ip=flow option.
The tunnel destination IP address for any packet received from a
tunnel is available in the tun_dst or tun_ipv6_dst field for
matching in the flow table.
options : in_key: optional string
Optional, not applicable for bareudp and srv6. The key that re‐
ceived packets must contain, one of:
• 0. The tunnel receives packets with no key or with a key
of 0. This is equivalent to specifying no options:in_key
at all.
• A positive 24-bit (for Geneve, VXLAN, and LISP), 32-bit
(for GRE) or 64-bit (for STT) number. The tunnel receives
only packets with the specified key.
• The word flow. The tunnel accepts packets with any key.
The key will be placed in the tun_id field for matching
in the flow table. The ovs-fields(7) manual page contains
additional information about matching fields in OpenFlow
flows.
options : out_key: optional string
Optional, not applicable for bareudp and srv6. The key to be set
on outgoing packets, one of:
• 0. Packets sent through the tunnel will have no key. This
is equivalent to specifying no options:out_key at all.
• A positive 24-bit (for Geneve, VXLAN and LISP), 32-bit
(for GRE) or 64-bit (for STT) number. Packets sent
through the tunnel will have the specified key.
• The word flow. Packets sent through the tunnel will have
the key set using the set_tunnel Nicira OpenFlow vendor
extension (0 is used in the absence of an action). The
ovs-fields(7) manual page contains additional information
about the Nicira OpenFlow vendor extensions.
options : dst_port: optional string
Optional. The tunnel transport layer destination port, for UDP
and TCP based tunnel protocols (Geneve, VXLAN, LISP, and STT).
options : key: optional string
Optional. Shorthand to set in_key and out_key at the same time.
options : tos: optional string
Optional. The value of the ToS bits to be set on the encapsulat‐
ing packet. ToS is interpreted as DSCP and ECN bits, ECN part
must be zero. It may also be the word inherit, in which case the
ToS will be copied from the inner packet if it is IPv4 or IPv6
(otherwise it will be 0). The ECN fields are always inherited.
Default is 0.
options : ttl: optional string
Optional. The TTL to be set on the encapsulating packet. It may
also be the word inherit, in which case the TTL will be copied
from the inner packet if it is IPv4 or IPv6 (otherwise it will
be the system default, typically 64). Default is the system de‐
fault TTL.
options : df_default: optional string, either true or false
Optional. If enabled, the Don’t Fragment bit will be set on tun‐
nel outer headers to allow path MTU discovery. Default is en‐
abled; set to false to disable.
options : egress_pkt_mark: optional string
Optional. The pkt_mark to be set on the encapsulating packet.
This option sets packet mark for the tunnel endpoint for all
tunnel packets including tunnel monitoring.
Tunnel Options: lisp only:
options : packet_type: optional string, either legacy_l3 or ptap
A LISP tunnel sends and receives only IPv4 and IPv6 packets.
This option controls what how the tunnel represents the packets
that it sends and receives:
• By default, or if this option is legacy_l3, the tunnel
represents packets as Ethernet frames for compatibility
with legacy OpenFlow controllers that expect this behav‐
ior.
• If this option is ptap, the tunnel represents packets us‐
ing the packet_type mechanism introduced in OpenFlow 1.5.
Tunnel Options: vxlan only:
options : exts: optional string
Optional. Comma separated list of optional VXLAN extensions to
enable. The following extensions are supported:
• gbp: VXLAN-GBP allows to transport the group policy con‐
text of a packet across the VXLAN tunnel to other network
peers. See the description of tun_gbp_id and
tun_gbp_flags in ovs-fields(7) for additional informa‐
tion.
(https://tools.ietf.org/html/draft-smith-vxlan-group-pol‐
icy)
• gpe: Support for Generic Protocol Encapsulation in accor‐
dance with IETF draft
https://tools.ietf.org/html/draft-ietf-nvo3-vxlan-gpe.
Without this option, a VXLAN packet always encapsulates
an Ethernet frame. With this option, an VXLAN packet may
also encapsulate an IPv4, IPv6, NSH, or MPLS packet.
options : packet_type: optional string, one of legacy_l2, legacy_l3, or
ptap
This option controls what types of packets the tunnel sends and
receives and how it represents them:
• By default, or if this option is legacy_l2, the tunnel
sends and receives only Ethernet frames.
• If this option is legacy_l3, the tunnel sends and re‐
ceives only non-Ethernet (L3) packet, but the packets are
represented as Ethernet frames for compatibility with
legacy OpenFlow controllers that expect this behavior.
This requires enabling gpe in options:exts.
• If this option is ptap, Open vSwitch represents packets
in the tunnel using the packet_type mechanism introduced
in OpenFlow 1.5. This mechanism supports any kind of
packet, but actually sending and receiving non-Ethernet
packets requires additionally enabling gpe in op‐
tions:exts.
Tunnel Options: gre only:
gre interfaces support these options.
options : packet_type: optional string, one of legacy_l2, legacy_l3, or
ptap
This option controls what types of packets the tunnel sends and
receives and how it represents them:
• By default, or if this option is legacy_l2, the tunnel
sends and receives only Ethernet frames.
• If this option is legacy_l3, the tunnel sends and re‐
ceives only non-Ethernet (L3) packet, but the packets are
represented as Ethernet frames for compatibility with
legacy OpenFlow controllers that expect this behavior.
• The legacy_l3 option is only available via the user space
datapath. The OVS kernel datapath does not support de‐
vices of type ARPHRD_IPGRE which is the requirement for
legacy_l3 type packets.
• If this option is ptap, the tunnel sends and receives any
kind of packet. Open vSwitch represents packets in the
tunnel using the packet_type mechanism introduced in
OpenFlow 1.5.
options : seq: optional string, either true or false
Optional. A 4-byte sequence number field for GRE tunnel only.
Default is disabled, set to true to enable. Sequence number is
incremented by one on each outgoing packet.
Tunnel Options: gre, ip6gre, geneve, bareudp and vxlan:
gre, ip6gre, geneve, bareudp and vxlan interfaces support these op‐
tions.
options : csum: optional string, either true or false
Optional. Compute encapsulation header (either GRE or UDP)
checksums on outgoing packets. When unset (the default value),
checksum computing for outgoing packets is enabled for UDP IPv6
tunnels, and disabled for GRE and IPv4 UDP tunnels. When set to
false, no checksums will be computed for outgoing tunnel encap‐
sulation headers. When true, checksums will be computed for all
outgoing tunnel encapsulation headers. Checksums present on in‐
coming packets will be validated regardless of this setting. In‐
coming packets without a checksum will also be accepted regard‐
less of this setting.
When using the upstream Linux kernel module, computation of
checksums for geneve and vxlan requires Linux kernel version 4.0
or higher. gre and ip6gre support checksums for all versions of
Open vSwitch that support GRE. The out of tree kernel module
distributed as part of OVS can compute all tunnel checksums on
any kernel version that it is compatible with.
Tunnel Options: IPsec:
Setting any of these options enables IPsec support for a given tunnel.
gre, geneve, vxlan and stt interfaces support these options. See the
IPsec section in the Open_vSwitch table for a description of each mode.
options : psk: optional string
In PSK mode only, the preshared secret to negotiate tunnel. This
value must match on both tunnel ends.
options : remote_cert: optional string
In self-signed certificate mode only, name of a PEM file con‐
taining a certificate of the remote switch. The certificate must
be x.509 version 3 and with the string in common name (CN) also
set in the subject alternative name (SAN).
options : remote_name: optional string
In CA-signed certificate mode only, common name (CN) of the re‐
mote certificate.
Tunnel Options: erspan only:
Only erspan interfaces support these options.
options : erspan_idx: optional string
20 bit index/port number associated with the ERSPAN traffic’s
source port and direction (ingress/egress). This field is plat‐
form dependent.
options : erspan_ver: optional string
ERSPAN version: 1 for version 1 (type II) or 2 for version 2
(type III).
options : erspan_dir: optional string
Specifies the ERSPAN v2 mirrored traffic’s direction. 1 for
egress traffic, and 0 for ingress traffic.
options : erspan_hwid: optional string
ERSPAN hardware ID is a 6-bit unique identifier of an ERSPAN v2
engine within a system.
Tunnel Options: Bareudp only:
options : payload_type: optional string
Specifies the ethertype of the l3 protocol the bareudp device is
tunnelling. For the tunnels which supports multiple ethertypes
of a l3 protocol (IP, MPLS) this field specifies the protocol
name as a string.
Tunnel Options: srv6 only:
options : srv6_segs: optional string
Specifies the segment list in Segment Routing Header (SRH). It
consists of a comma-separated list of segments represented in
IPv6 format, e.g. "fc00:100::1,fc00:200::1,fc00:300::1". Note
that the first segment must be the same as options:remote_ip.
options : srv6_flowlabel: optional string, one of compute, copy, or
zero
Optional. This option controls how flowlabel in outer IPv6
header is configured. It gives the benefit of IPv6 flow label
based load balancing, which is supported by some popular vendor
appliances. Like net.ipv6.seg6_flowlabel sysconfig, it is one of
the three values below:
• By default, or if this option is copy, copy the flowlabel
of inner IPv6 header to the flowlabel of outer IPv6
header. If inner header is not IPv6, it is set to 0.
• If this option is zero, simply set flowlabel to 0.
• If this option is compute, set flowlabel to a hash over
the L3/L4 fields of the inner packet.
Patch Options:
These options apply only to patch ports, that is, interfaces whose type
column is patch. Patch ports are mainly a way to connect otherwise in‐
dependent bridges to one another, similar to how one might plug an Eth‐
ernet cable (a ``patch cable’’) into two physical switches to connect
those switches. The effect of plugging a patch port into two switches
is conceptually similar to that of plugging the two ends of a Linux
veth device into those switches, but the implementation of patch ports
makes them much more efficient.
Patch ports may connect two different bridges (the usual case) or the
same bridge. In the latter case, take special care to avoid loops, e.g.
by programming appropriate flows with OpenFlow. Patch ports do not work
if its ends are attached to bridges on different datapaths, e.g. to
connect bridges in system and netdev datapaths.
The following command creates and connects patch ports p0 and p1 and
adds them to bridges br0 and br1, respectively:
ovs-vsctl add-port br0 p0 -- set Interface p0 type=patch options:peer=p1 \
-- add-port br1 p1 -- set Interface p1 type=patch options:peer=p0
options : peer: optional string
The name of the Interface for the other side of the patch. The
named Interface’s own peer option must specify this Interface’s
name. That is, the two patch interfaces must have reversed name
and peer values.
PMD (Poll Mode Driver) Options:
Only PMD netdevs support these options.
options : n_rxq: optional string, containing an integer, at least 1
Specifies the maximum number of rx queues to be created for PMD
netdev. If not specified or specified to 0, one rx queue will be
created by default. Not supported by DPDK vHost interfaces.
options : dpdk-devargs: optional string
Specifies the PCI address associated with the port for physical
devices, or the virtual driver to be used for the port when a
virtual PMD is intended to be used. For the latter, the argument
string typically takes the form of eth_driver_namex, where dri‐
ver_name is a valid virtual DPDK PMD driver name and x is a
unique identifier of your choice for the given port. Only sup‐
ported by the dpdk port type.
other_config : pmd-rxq-affinity: optional string
Specifies mapping of RX queues of this interface to CPU cores.
Value should be set in the following form:
other_config:pmd-rxq-affinity=<rxq-affinity-list>
where
• <rxq-affinity-list> ::= NULL | <non-empty-list>
• <non-empty-list> ::= <affinity-pair> | <affinity-pair> ,
<non-empty-list>
• <affinity-pair> ::= <queue-id> : <core-id>
options : xdp-mode: optional string, one of best-effort, generic, na‐
tive-with-zerocopy, or native
Specifies the operational mode of the XDP program.
In native-with-zerocopy mode the XDP program is loaded into the
device driver with zero-copy RX and TX enabled. This mode re‐
quires device driver support and has the best performance be‐
cause there should be no copying of packets.
native is the same as native-with-zerocopy, but without zero-
copy capability. This requires at least one copy between kernel
and the userspace. This mode also requires support from device
driver.
In generic case the XDP program in kernel works after skb allo‐
cation on early stages of packet processing inside the network
stack. This mode doesn’t require driver support, but has much
lower performance.
best-effort tries to detect and choose the best (fastest) from
the available modes for current interface.
Note that this option is specific to netdev-afxdp. Defaults to
best-effort mode.
options : use-need-wakeup: optional string, either true or false
Specifies whether to use need_wakeup feature in afxdp netdev. If
enabled, OVS explicitly wakes up the kernel RX, using poll()
syscall and wakes up TX, using sendto() syscall. For physical
devices, this feature improves the performance by avoiding un‐
necessary sendto syscalls. Defaults to true if supported by
libbpf.
options : vhost-server-path: optional string
The value specifies the path to the socket associated with a
vHost User client mode device that has been or will be created
by QEMU. Only supported by dpdkvhostuserclient interfaces.
options : tx-retries-max: optional string, containing an integer, in
range 0 to 32
The value specifies the maximum amount of vhost tx retries that
can be made while trying to send a batch of packets to an inter‐
face. Only supported by dpdkvhostuserclient interfaces.
Default value is 8.
options : n_rxq_desc: optional string, containing an integer, in range
1 to 4,096
Specifies the rx queue size (number rx descriptors) for dpdk
ports. The value must be a power of 2, less than 4096 and sup‐
ported by the hardware of the device being configured. If not
specified or an incorrect value is specified, 2048 rx descrip‐
tors will be used by default.
options : n_txq_desc: optional string, containing an integer, in range
1 to 4,096
Specifies the tx queue size (number tx descriptors) for dpdk
ports. The value must be a power of 2, less than 4096 and sup‐
ported by the hardware of the device being configured. If not
specified or an incorrect value is specified, 2048 tx descrip‐
tors will be used by default.
options : dpdk-vf-mac: optional string
Ethernet address to set for this VF interface. If unset then the
default MAC address is used:
• For most drivers, the default MAC address assigned by
their hardware.
• For bifurcated drivers, the MAC currently used by the
kernel netdevice.
This option may only be used with dpdk VF representors.
options : rx-steering: optional string, either rss+lacp or rss
Configure hardware Rx queue steering policy.
This option takes one of the following values:
rss Distribution of ingress packets in all Rx queues accord‐
ing to the RSS algorithm. This is the default behaviour.
rss+lacp
Distribution of ingress packets according to the RSS al‐
gorithm on all but the last Rx queue. An extra Rx queue
is allocated for LACP packets.
If the user has already configured multiple options:n_rxq on the
port, an additional one will be allocated for the specified pro‐
tocols. Even if the hardware cannot satisfy the requested number
of requested Rx queues, the last Rx queue will be used. If only
one Rx queue is available or if the hardware does not support
the rte_flow matchers/actions required to redirect the selected
protocols, custom rx-steering will fall back to default rss
mode.
This feature is mutually exclusive with other_config:hw-offload
as it may conflict with the offloaded flows. If both are en‐
abled, rx-steering will fall back to default rss mode.
This option is only applicable to interfaces with type dpdk.
other_config : tx-steering: optional string, either hash or thread
Specifies the Tx steering mode for the interface.
thread enables static (1:1) thread-to-txq mapping when the num‐
ber of Tx queues is greater than number of PMD threads, and dy‐
namic (N:1) mapping if equal or lower. In this mode a single
thread can not use more than 1 transmit queue of a given port.
hash enables hash-based Tx steering, which distributes the pack‐
ets on all the transmit queues based on their 5-tuples hashes.
Defaults to thread.
EMC (Exact Match Cache) Configuration:
These settings controls behaviour of EMC lookups/insertions for packets
received from the interface.
other_config : emc-enable: optional string, either true or false
Specifies if Exact Match Cache (EMC) should be used while pro‐
cessing packets received from this interface. If true,
other_config:emc-insert-inv-prob will have effect on this inter‐
face.
Defaults to true.
MTU:
The MTU (maximum transmission unit) is the largest amount of data that
can fit into a single Ethernet frame. The standard Ethernet MTU is 1500
bytes. Some physical media and many kinds of virtual interfaces can be
configured with higher MTUs.
A client may change an interface MTU by filling in mtu_request. Open
vSwitch then reports in mtu the currently configured value.
mtu: optional integer
The currently configured MTU for the interface.
This column will be empty for an interface that does not have an
MTU as, for example, some kinds of tunnels do not.
Open vSwitch sets this column’s value, so other clients should
treat it as read-only.
mtu_request: optional integer, at least 1
Requested MTU (Maximum Transmission Unit) for the interface. A
client can fill this column to change the MTU of an interface.
RFC 791 requires every internet module to be able to forward a
datagram of 68 octets without further fragmentation. The maximum
size of an IP packet is 65535 bytes.
If this is not set and if the interface has internal type, Open
vSwitch will change the MTU to match the minimum of the other
interfaces in the bridge.
Interface Status:
Status information about interfaces attached to bridges, updated every
5 seconds. Not all interfaces have all of these properties; virtual in‐
terfaces don’t have a link speed, for example. Non-applicable columns
will have empty values.
admin_state: optional string, either down or up
The administrative state of the physical network link.
link_state: optional string, either down or up
The observed state of the physical network link. This is ordi‐
narily the link’s carrier status. If the interface’s Port is a
bond configured for miimon monitoring, it is instead the network
link’s miimon status.
link_resets: optional integer
The number of times Open vSwitch has observed the link_state of
this Interface change.
link_speed: optional integer
The negotiated speed of the physical network link. Valid values
are positive integers greater than 0.
duplex: optional string, either full or half
The duplex mode of the physical network link.
lacp_current: optional boolean
Boolean value indicating LACP status for this interface. If
true, this interface has current LACP information about its LACP
partner. This information may be used to monitor the health of
interfaces in a LACP enabled port. This column will be empty if
LACP is not enabled.
status: map of string-string pairs
Key-value pairs that report port status. Supported status values
are type-dependent; some interfaces may not have a valid sta‐
tus:driver_name, for example.
status : driver_name: optional string
The name of the device driver controlling the network adapter.
status : driver_version: optional string
The version string of the device driver controlling the network
adapter.
status : firmware_version: optional string
The version string of the network adapter’s firmware, if avail‐
able.
status : source_ip: optional string
The source IP address used for an IPv4/IPv6 tunnel end-point,
such as gre.
status : tunnel_egress_iface: optional string
Egress interface for tunnels. Currently only relevant for tun‐
nels on Linux systems, this column will show the name of the in‐
terface which is responsible for routing traffic destined for
the configured options:remote_ip. This could be an internal in‐
terface such as a bridge port.
status : tunnel_egress_iface_carrier: optional string, either down or
up
Whether carrier is detected on status:tunnel_egress_iface.
dpdk:
DPDK specific interface status options.
status : port_no: optional string
DPDK port ID.
status : numa_id: optional string
NUMA socket ID to which an Ethernet device is connected.
status : min_rx_bufsize: optional string
Minimum size of RX buffer.
status : max_rx_pktlen: optional string
Maximum configurable length of RX pkt.
status : max_rx_queues: optional string
Maximum number of RX queues.
status : max_tx_queues: optional string
Maximum number of TX queues.
status : max_mac_addrs: optional string
Maximum number of MAC addresses.
status : max_hash_mac_addrs: optional string
Maximum number of hash MAC addresses for MTA and UTA.
status : max_vfs: optional string
Maximum number of hash MAC addresses for MTA and UTA. Maximum
number of VFs.
status : max_vmdq_pools: optional string
Maximum number of VMDq pools.
status : n_rxq: optional string
Number of Rx queues.
status : n_txq: optional string
Number of Tx queues.
status : rx_csum_offload: optional string
Whether Rx Checksum offload is enabled or not.
status : if_type: optional string
Interface type ID according to IANA ifTYPE MIB definitions.
status : if_descr: optional string
Interface description string.
status : bus_info: optional string
Bus name and bus info such as Vendor ID and Device ID of PCI de‐
vice.
status : dpdk-vf-mac: optional string
Ethernet address set for this VF interface. Only reported for
dpdk VF representors.
status : rx-steering: optional string
Hardware Rx queue steering policy in use.
status : rx_steering_queue: optional string
ID of rx steering queue. Only reported if rx-steering is sup‐
ported by hardware.
status : rss_queues: optional string
IDs of rss queues. Only reported if rx-steering is supported by
hardware.
dpdkvhostuser:
dpdkvhostuser and dpdkvhostuserclient netdev specific interface status
information.
status : mode: optional string
client (connecting) or server (listening) in the socket communi‐
cation.
status : features: optional string
virtio features bitmap as per virtio specification.
status : num_of_vrings: optional string
The number of available virtqueues.
status : numa: optional string
The numa id of the device and guest memory.
status : socket: optional string
The path to the socket used for communication.
status : status: optional string
Status of connection to the device.
status : vring_n_size: optional string
Each virtqueue will have it’s size reported, where n is the
virtqueue number from 0..(num_of_vrings-1).
status : userspace-tso: optional string
Whether userspace-tso is enabled or disabled.
afxdp:
AF_XDP specific interface status options.
status : xdp-mode: optional string
XDP mode currently in use. See options:xdp-mode for description
of possible values.
Statistics:
Key-value pairs that report interface statistics. The current implemen‐
tation updates these counters periodically. The update period is con‐
trolled by other_config:stats-update-interval in the Open_vSwitch ta‐
ble. Future implementations may update them when an interface is cre‐
ated, when they are queried (e.g. using an OVSDB select operation), and
just before an interface is deleted due to virtual interface hot-unplug
or VM shutdown, and perhaps at other times, but not on any regular pe‐
riodic basis.
These are the same statistics reported by OpenFlow in its struct
ofp_port_stats structure. If an interface does not support a given sta‐
tistic, then that pair is omitted.
Statistics: Successful transmit and receive counters:
statistics : rx_packets: optional integer
Number of received packets.
statistics : rx_bytes: optional integer
Number of received bytes.
statistics : tx_packets: optional integer
Number of transmitted packets.
statistics : tx_bytes: optional integer
Number of transmitted bytes.
Statistics: Receive errors:
statistics : rx_dropped: optional integer
Number of packets dropped by RX.
statistics : rx_frame_err: optional integer
Number of frame alignment errors.
statistics : rx_over_err: optional integer
Number of packets with RX overrun.
statistics : rx_crc_err: optional integer
Number of CRC errors.
statistics : rx_errors: optional integer
Total number of receive errors, greater than or equal to the sum
of the above.
Statistics: Transmit errors:
statistics : tx_dropped: optional integer
Number of packets dropped by TX.
statistics : collisions: optional integer
Number of collisions.
statistics : tx_errors: optional integer
Total number of transmit errors, greater than or equal to the
sum of the above.
Ingress Policing:
These settings control ingress policing for packets received on this
interface. On a physical interface, this limits the rate at which traf‐
fic is allowed into the system from the outside; on a virtual interface
(one connected to a virtual machine), this limits the rate at which the
VM is able to transmit.
Policing is a simple form of quality-of-service that simply drops pack‐
ets received in excess of the configured rate. Due to its simplicity,
policing is usually less accurate and less effective than egress QoS
(which is configured using the QoS and Queue tables).
Policing settings can be set with byte rate or packet rate, and they
can be configured together, in which case they take effect together,
that means the smaller speed limit of them is in effect.
Currently, byte rate policing is implemented on Linux and OVS with
DPDK, while packet rate policing is only implemented on Linux. Both
Linux and OVS DPDK implementations use a simple ``token bucket’’ ap‐
proach.
Byte rate policing:
• The size of the bucket corresponds to ingress_polic‐
ing_burst. Initially the bucket is full.
• Whenever a packet is received, its size (converted to to‐
kens) is compared to the number of tokens currently in
the bucket. If the required number of tokens are avail‐
able, they are removed and the packet is forwarded. Oth‐
erwise, the packet is dropped.
• Whenever it is not full, the bucket is refilled with to‐
kens at the rate specified by ingress_policing_rate.
Packet rate policing:
• The size of the bucket corresponds to ingress_polic‐
ing_kpkts_burst. Initially the bucket is full.
• Whenever a packet is received, it will consume one token
from the current bucket. If the token is available in the
bucket, it’s removed and the packet is forwarded. Other‐
wise, the packet is dropped.
• Whenever it is not full, the bucket is refilled with to‐
kens at the rate specified by ingress_policing_kp‐
kts_rate.
Policing interacts badly with some network protocols, and especially
with fragmented IP packets. Suppose that there is enough network activ‐
ity to keep the bucket nearly empty all the time. Then this token
bucket algorithm will forward a single packet every so often, with the
period depending on packet size and on the configured rate. All of the
fragments of an IP packets are normally transmitted back-to-back, as a
group. In such a situation, therefore, only one of these fragments will
be forwarded and the rest will be dropped. IP does not provide any way
for the intended recipient to ask for only the remaining fragments. In
such a case there are two likely possibilities for what will happen
next: either all of the fragments will eventually be retransmitted (as
TCP will do), in which case the same problem will recur, or the sender
will not realize that its packet has been dropped and data will simply
be lost (as some UDP-based protocols will do). Either way, it is possi‐
ble that no forward progress will ever occur.
ingress_policing_rate: integer, at least 0
Maximum rate for data received on this interface, in kbps. Data
received faster than this rate is dropped. Set to 0 (the de‐
fault) to disable policing.
ingress_policing_kpkts_rate: integer, at least 0
Maximum rate for data received on this interface, in kpps (1
kpps is 1000 pps). Data received faster than this rate is
dropped. Set to 0 (the default) to disable policing.
ingress_policing_burst: integer, at least 0
Maximum burst size for data received on this interface, in kb.
The default burst size if set to 0 is 8000 kbit. This value has
no effect if ingress_policing_rate is 0.
Specifying a larger burst size lets the algorithm be more for‐
giving, which is important for protocols like TCP that react se‐
verely to dropped packets. The burst size should be at least the
size of the interface’s MTU. Specifying a value that is numeri‐
cally at least as large as 80% of ingress_policing_rate helps
TCP come closer to achieving the full rate.
ingress_policing_kpkts_burst: integer, at least 0
Maximum burst size for data received on this interface, in kpkts
(1 kpkts is 1000 packets). The default burst size if set to 0 is
16 kpkts. This value has no effect if ingress_policing_kp‐
kts_rate is 0.
Specifying a larger burst size lets the algorithm be more for‐
giving, which is important for protocols like TCP that react se‐
verely to dropped packets. Specifying a value that is numeri‐
cally at least as large as 80% of ingress_policing_kpkts_rate
helps TCP come closer to achieving the full rate.
Bidirectional Forwarding Detection (BFD):
BFD, defined in RFC 5880 and RFC 5881, allows point-to-point detection
of connectivity failures by occasional transmission of BFD control mes‐
sages. Open vSwitch implements BFD to serve as a more popular and stan‐
dards compliant alternative to CFM.
BFD operates by regularly transmitting BFD control messages at a rate
negotiated independently in each direction. Each endpoint specifies the
rate at which it expects to receive control messages, and the rate at
which it is willing to transmit them. By default, Open vSwitch uses a
detection multiplier of three, meaning that an endpoint signals a con‐
nectivity fault if three consecutive BFD control messages fail to ar‐
rive. In the case of a unidirectional connectivity issue, the system
not receiving BFD control messages signals the problem to its peer in
the messages it transmits.
The Open vSwitch implementation of BFD aims to comply faithfully with
RFC 5880 requirements. Open vSwitch does not implement the optional Au‐
thentication or ``Echo Mode’’ features.
OVS 2.13 and earlier intercepted and processed all BFD packets. OVS
2.14 and later only intercept and process BFD packets destined to a
configured BFD instance, and other BFD packets are made available to
the OVS flow table for forwarding.
BFD Configuration:
A controller sets up key-value pairs in the bfd column to enable and
configure BFD.
bfd : enable: optional string, either true or false
True to enable BFD on this Interface. If not specified, BFD will
not be enabled by default.
bfd : min_rx: optional string, containing an integer, at least 1
The shortest interval, in milliseconds, at which this BFD ses‐
sion offers to receive BFD control messages. The remote endpoint
may choose to send messages at a slower rate. Defaults to 1000.
bfd : min_tx: optional string, containing an integer, at least 1
The shortest interval, in milliseconds, at which this BFD ses‐
sion is willing to transmit BFD control messages. Messages will
actually be transmitted at a slower rate if the remote endpoint
is not willing to receive as quickly as specified. Defaults to
100.
bfd : decay_min_rx: optional string, containing an integer
An alternate receive interval, in milliseconds, that must be
greater than or equal to bfd:min_rx. The implementation switches
from bfd:min_rx to bfd:decay_min_rx when there is no obvious in‐
coming data traffic at the interface, to reduce the CPU and
bandwidth cost of monitoring an idle interface. This feature may
be disabled by setting a value of 0. This feature is reset when‐
ever bfd:decay_min_rx or bfd:min_rx changes.
bfd : forwarding_if_rx: optional string, either true or false
When true, traffic received on the Interface is used to indicate
the capability of packet I/O. BFD control packets are still
transmitted and received. At least one BFD control packet must
be received every 100 * bfd:min_rx amount of time. Otherwise,
even if traffic are received, the bfd:forwarding will be false.
bfd : cpath_down: optional string, either true or false
Set to true to notify the remote endpoint that traffic should
not be forwarded to this system for some reason other than a
connectivty failure on the interface being monitored. The typi‐
cal underlying reason is ``concatenated path down,’’ that is,
that connectivity beyond the local system is down. Defaults to
false.
bfd : check_tnl_key: optional string, either true or false
Set to true to make BFD accept only control messages with a tun‐
nel key of zero. By default, BFD accepts control messages with
any tunnel key.
bfd : bfd_local_src_mac: optional string
Set to an Ethernet address in the form xx:xx:xx:xx:xx:xx to set
the MAC used as source for transmitted BFD packets. The default
is the mac address of the BFD enabled interface.
bfd : bfd_local_dst_mac: optional string
Set to an Ethernet address in the form xx:xx:xx:xx:xx:xx to set
the MAC used as destination for transmitted BFD packets. The de‐
fault is 00:23:20:00:00:01.
bfd : bfd_remote_dst_mac: optional string
Set to an Ethernet address in the form xx:xx:xx:xx:xx:xx to set
the MAC used for checking the destination of received BFD pack‐
ets. Packets with different destination MAC will not be consid‐
ered as BFD packets. If not specified the destination MAC ad‐
dress of received BFD packets are not checked.
bfd : bfd_src_ip: optional string
Set to an IPv4 address to set the IP address used as source for
transmitted BFD packets. The default is 169.254.1.1.
bfd : bfd_dst_ip: optional string
Set to an IPv4 address to set the IP address used as destination
for transmitted BFD packets. The default is 169.254.1.0.
bfd : oam: optional string
Some tunnel protocols (such as Geneve) include a bit in the
header to indicate that the encapsulated packet is an OAM frame.
By setting this to true, BFD packets will be marked as OAM if
encapsulated in one of these tunnels.
bfd : mult: optional string, containing an integer, in range 1 to 255
The BFD detection multiplier, which defaults to 3. An endpoint
signals a connectivity fault if the given number of consecutive
BFD control messages fail to arrive.
BFD Status:
The switch sets key-value pairs in the bfd_status column to report the
status of BFD on this interface. When BFD is not enabled, with bfd:en‐
able, the switch clears all key-value pairs from bfd_status.
bfd_status : state: optional string, one of admin_down, down, init, or
up
Reports the state of the BFD session. The BFD session is fully
healthy and negotiated if UP.
bfd_status : forwarding: optional string, either true or false
Reports whether the BFD session believes this Interface may be
used to forward traffic. Typically this means the local session
is signaling UP, and the remote system isn’t signaling a problem
such as concatenated path down.
bfd_status : diagnostic: optional string
A diagnostic code specifying the local system’s reason for the
last change in session state. The error messages are defined in
section 4.1 of [RFC 5880].
bfd_status : remote_state: optional string, one of admin_down, down,
init, or up
Reports the state of the remote endpoint’s BFD session.
bfd_status : remote_diagnostic: optional string
A diagnostic code specifying the remote system’s reason for the
last change in session state. The error messages are defined in
section 4.1 of [RFC 5880].
bfd_status : flap_count: optional string, containing an integer, at
least 0
Counts the number of bfd_status:forwarding flaps since start. A
flap is considered as a change of the bfd_status:forwarding
value.
Connectivity Fault Management:
802.1ag Connectivity Fault Management (CFM) allows a group of Mainte‐
nance Points (MPs) called a Maintenance Association (MA) to detect con‐
nectivity problems with each other. MPs within a MA should have com‐
plete and exclusive interconnectivity. This is verified by occasionally
broadcasting Continuity Check Messages (CCMs) at a configurable trans‐
mission interval.
According to the 802.1ag specification, each Maintenance Point should
be configured out-of-band with a list of Remote Maintenance Points it
should have connectivity to. Open vSwitch differs from the specifica‐
tion in this area. It simply assumes the link is faulted if no Remote
Maintenance Points are reachable, and considers it not faulted other‐
wise.
When operating over tunnels which have no in_key, or an in_key of flow.
CFM will only accept CCMs with a tunnel key of zero.
cfm_mpid: optional integer
A Maintenance Point ID (MPID) uniquely identifies each endpoint
within a Maintenance Association. The MPID is used to identify
this endpoint to other Maintenance Points in the MA. Each end of
a link being monitored should have a different MPID. Must be
configured to enable CFM on this Interface.
According to the 802.1ag specification, MPIDs can only range be‐
tween [1, 8191]. However, extended mode (see other_con‐
fig:cfm_extended) supports eight byte MPIDs.
cfm_flap_count: optional integer
Counts the number of cfm fault flapps since boot. A flap is con‐
sidered to be a change of the cfm_fault value.
cfm_fault: optional boolean
Indicates a connectivity fault triggered by an inability to re‐
ceive heartbeats from any remote endpoint. When a fault is trig‐
gered on Interfaces participating in bonds, they will be dis‐
abled.
Faults can be triggered for several reasons. Most importantly
they are triggered when no CCMs are received for a period of 3.5
times the transmission interval. Faults are also triggered when
any CCMs indicate that a Remote Maintenance Point is not receiv‐
ing CCMs but able to send them. Finally, a fault is triggered if
a CCM is received which indicates unexpected configuration. No‐
tably, this case arises when a CCM is received which advertises
the local MPID.
cfm_fault_status : recv: none
Indicates a CFM fault was triggered due to a lack of CCMs re‐
ceived on the Interface.
cfm_fault_status : rdi: none
Indicates a CFM fault was triggered due to the reception of a
CCM with the RDI bit flagged. Endpoints set the RDI bit in their
CCMs when they are not receiving CCMs themselves. This typically
indicates a unidirectional connectivity failure.
cfm_fault_status : maid: none
Indicates a CFM fault was triggered due to the reception of a
CCM with a MAID other than the one Open vSwitch uses. CFM broad‐
casts are tagged with an identification number in addition to
the MPID called the MAID. Open vSwitch only supports receiving
CCM broadcasts tagged with the MAID it uses internally.
cfm_fault_status : loopback: none
Indicates a CFM fault was triggered due to the reception of a
CCM advertising the same MPID configured in the cfm_mpid column
of this Interface. This may indicate a loop in the network.
cfm_fault_status : overflow: none
Indicates a CFM fault was triggered because the CFM module re‐
ceived CCMs from more remote endpoints than it can keep track
of.
cfm_fault_status : override: none
Indicates a CFM fault was manually triggered by an administrator
using an ovs-appctl command.
cfm_fault_status : interval: none
Indicates a CFM fault was triggered due to the reception of a
CCM frame having an invalid interval.
cfm_remote_opstate: optional string, either down or up
When in extended mode, indicates the operational state of the
remote endpoint as either up or down. See other_config:cfm_op‐
state.
cfm_health: optional integer, in range 0 to 100
Indicates the health of the interface as a percentage of CCM
frames received over 21 other_config:cfm_intervals. The health
of an interface is undefined if it is communicating with more
than one cfm_remote_mpids. It reduces if healthy heartbeats are
not received at the expected rate, and gradually improves as
healthy heartbeats are received at the desired rate. Every 21
other_config:cfm_intervals, the health of the interface is re‐
freshed.
As mentioned above, the faults can be triggered for several rea‐
sons. The link health will deteriorate even if heartbeats are
received but they are reported to be unhealthy. An unhealthy
heartbeat in this context is a heartbeat for which either some
fault is set or is out of sequence. The interface health can be
100 only on receiving healthy heartbeats at the desired rate.
cfm_remote_mpids: set of integers
When CFM is properly configured, Open vSwitch will occasionally
receive CCM broadcasts. These broadcasts contain the MPID of the
sending Maintenance Point. The list of MPIDs from which this In‐
terface is receiving broadcasts from is regularly collected and
written to this column.
other_config : cfm_interval: optional string, containing an integer
The interval, in milliseconds, between transmissions of CFM
heartbeats. Three missed heartbeat receptions indicate a connec‐
tivity fault.
In standard operation only intervals of 3, 10, 100, 1,000,
10,000, 60,000, or 600,000 ms are supported. Other values will
be rounded down to the nearest value on the list. Extended mode
(see other_config:cfm_extended) supports any interval up to
65,535 ms. In either mode, the default is 1000 ms.
We do not recommend using intervals less than 100 ms.
other_config : cfm_extended: optional string, either true or false
When true, the CFM module operates in extended mode. This causes
it to use a nonstandard destination address to avoid conflicting
with compliant implementations which may be running concurrently
on the network. Furthermore, extended mode increases the accu‐
racy of the cfm_interval configuration parameter by breaking
wire compatibility with 802.1ag compliant implementations. And
extended mode allows eight byte MPIDs. Defaults to false.
other_config : cfm_demand: optional string, either true or false
When true, and other_config:cfm_extended is true, the CFM module
operates in demand mode. When in demand mode, traffic received
on the Interface is used to indicate liveness. CCMs are still
transmitted and received. At least one CCM must be received
every 100 * other_config:cfm_interval amount of time. Otherwise,
even if traffic are received, the CFM module will raise the con‐
nectivity fault.
Demand mode has a couple of caveats:
• To ensure that ovs-vswitchd has enough time to pull sta‐
tistics from the datapath, the fault detection interval
is set to 3.5 * MAX(other_config:cfm_interval, 500) ms.
• To avoid ambiguity, demand mode disables itself when
there are multiple remote maintenance points.
• If the Interface is heavily congested, CCMs containing
the other_config:cfm_opstate status may be dropped caus‐
ing changes in the operational state to be delayed. Simi‐
larly, if CCMs containing the RDI bit are not received,
unidirectional link failures may not be detected.
other_config : cfm_opstate: optional string, either down or up
When down, the CFM module marks all CCMs it generates as opera‐
tionally down without triggering a fault. This allows remote
maintenance points to choose not to forward traffic to the In‐
terface on which this CFM module is running. Currently, in Open
vSwitch, the opdown bit of CCMs affects Interfaces participating
in bonds, and the bundle OpenFlow action. This setting is ig‐
nored when CFM is not in extended mode. Defaults to up.
other_config : cfm_ccm_vlan: optional string, containing an integer, in
range 1 to 4,095
When set, the CFM module will apply a VLAN tag to all CCMs it
generates with the given value. May be the string random in
which case each CCM will be tagged with a different randomly
generated VLAN.
other_config : cfm_ccm_pcp: optional string, containing an integer, in
range 1 to 7
When set, the CFM module will apply a VLAN tag to all CCMs it
generates with the given PCP value, the VLAN ID of the tag is
governed by the value of other_config:cfm_ccm_vlan. If
other_config:cfm_ccm_vlan is unset, a VLAN ID of zero is used.
Bonding Configuration:
other_config : lacp-port-id: optional string, containing an integer, in
range 1 to 65,535
The LACP port ID of this Interface. Port IDs are used in LACP
negotiations to identify individual ports participating in a
bond.
other_config : lacp-port-priority: optional string, containing an inte‐
ger, in range 1 to 65,535
The LACP port priority of this Interface. In LACP negotiations
Interfaces with numerically lower priorities are preferred for
aggregation.
other_config : lacp-aggregation-key: optional string, containing an in‐
teger, in range 1 to 65,535
The LACP aggregation key of this Interface. Interfaces with dif‐
ferent aggregation keys may not be active within a given Port at
the same time.
Virtual Machine Identifiers:
These key-value pairs specifically apply to an interface that repre‐
sents a virtual Ethernet interface connected to a virtual machine.
These key-value pairs should not be present for other types of inter‐
faces. Keys whose names end in -uuid have values that uniquely identify
the entity in question.
external_ids : attached-mac: optional string
The MAC address programmed into the ``virtual hardware’’ for
this interface, in the form xx:xx:xx:xx:xx:xx.
external_ids : iface-id: optional string
A system-unique identifier for the interface.
external_ids : iface-status: optional string, either active or inactive
Hypervisors may sometimes have more than one interface associ‐
ated with a given external_ids:iface-id, only one of which is
actually in use at a given time. For example, in some circum‐
stances hypervisor may have both a ``tap’’ and a ``vif’’ inter‐
face for a single external_ids:iface-id, but only uses one of
them at a time. A hypervisor that behaves this way must mark the
currently in use interface active and the others inactive. A hy‐
pervisor that never has more than one interface for a given ex‐
ternal_ids:iface-id may mark that interface active or omit ex‐
ternal_ids:iface-status entirely.
During VM migration, a given external_ids:iface-id might tran‐
siently be marked active on two different hypervisors. That is,
active means that this external_ids:iface-id is the active in‐
stance within a single hypervisor, not in a broader scope. There
is one exception: some hypervisors support ``migration’’ from a
given hypervisor to itself (most often for test purposes). Dur‐
ing such a ``migration,’’ two instances of a single exter‐
nal_ids:iface-id might both be briefly marked active on a single
hypervisor.
external_ids : vm-id: optional string
The VM to which this interface belongs.
Auto Attach Configuration:
Auto Attach configuration for a particular interface.
lldp : enable: optional string, either true or false
True to enable LLDP on this Interface. If not specified, LLDP
will be disabled by default.
Flow control Configuration:
Ethernet flow control defined in IEEE 802.1Qbb provides link level flow
control using MAC pause frames. Implemented only for interfaces with
type dpdk.
options : rx-flow-ctrl: optional string, either true or false
Set to true to enable Rx flow control on physical ports. By de‐
fault, Rx flow control is disabled.
options : tx-flow-ctrl: optional string, either true or false
Set to true to enable Tx flow control on physical ports. By de‐
fault, Tx flow control is disabled.
options : flow-ctrl-autoneg: optional string, either true or false
Set to true to enable flow control auto negotiation on physical
ports. By default, auto-neg is disabled.
Link State Change detection mode:
options : dpdk-lsc-interrupt: optional string, either true or false
Set this value to false to configure poll mode for Link State
Change (LSC) detection instead of interrupt mode for the DPDK
interface.
If this value is not set, interrupt mode is configured.
This parameter has an effect only on netdev dpdk interfaces.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
other_config: map of string-string pairs
external_ids: map of string-string pairs
Flow_Table TABLE
Configuration for a particular OpenFlow table.
Summary:
name optional string
Eviction Policy:
flow_limit optional integer, at least 0
overflow_policy optional string, either evict or refuse
groups set of strings
Classifier Optimization:
prefixes set of up to 3 strings
Common Columns:
external_ids map of string-string pairs
Details:
name: optional string
The table’s name. Set this column to change the name that con‐
trollers will receive when they request table statistics, e.g.
ovs-ofctl dump-tables. The name does not affect switch behavior.
Eviction Policy:
Open vSwitch supports limiting the number of flows that may be in‐
stalled in a flow table, via the flow_limit column. When adding a flow
would exceed this limit, by default Open vSwitch reports an error, but
there are two ways to configure Open vSwitch to instead delete
(``evict’’) a flow to make room for the new one:
• Set the overflow_policy column to evict.
• Send an OpenFlow 1.4+ ``table mod request’’ to enable
eviction for the flow table (e.g. ovs-ofctl -O OpenFlow14
mod-table br0 0 evict to enable eviction on flow table 0
of bridge br0).
When a flow must be evicted due to overflow, the flow to evict is cho‐
sen through an approximation of the following algorithm. This algorithm
is used regardless of how eviction was enabled:
1. Divide the flows in the table into groups based on the val‐
ues of the fields or subfields specified in the groups col‐
umn, so that all of the flows in a given group have the same
values for those fields. If a flow does not specify a given
field, that field’s value is treated as 0. If groups is
empty, then all of the flows in the flow table are treated
as a single group.
2. Consider the flows in the largest group, that is, the group
that contains the greatest number of flows. If two or more
groups all have the same largest number of flows, consider
the flows in all of those groups.
3. If the flows under consideration have different importance
values, eliminate from consideration any flows except those
with the lowest importance. (``Importance,’’ a 16-bit inte‐
ger value attached to each flow, was introduced in OpenFlow
1.4. Flows inserted with older versions of OpenFlow always
have an importance of 0.)
4. Among the flows under consideration, choose the flow that
expires soonest for eviction.
The eviction process only considers flows that have an idle timeout or
a hard timeout. That is, eviction never deletes permanent flows. (Per‐
manent flows do count against flow_limit.)
flow_limit: optional integer, at least 0
If set, limits the number of flows that may be added to the ta‐
ble. Open vSwitch may limit the number of flows in a table for
other reasons, e.g. due to hardware limitations or for resource
availability or performance reasons.
overflow_policy: optional string, either evict or refuse
Controls the switch’s behavior when an OpenFlow flow table modi‐
fication request would add flows in excess of flow_limit. The
supported values are:
refuse Refuse to add the flow or flows. This is also the default
policy when overflow_policy is unset.
evict Delete a flow chosen according to the algorithm described
above.
groups: set of strings
When overflow_policy is evict, this controls how flows are cho‐
sen for eviction when the flow table would otherwise exceed
flow_limit flows. Its value is a set of NXM fields or sub-
fields, each of which takes one of the forms field[] or
field[start..end], e.g. NXM_OF_IN_PORT[]. Please see meta-flow.h
for a complete list of NXM field names.
Open vSwitch ignores any invalid or unknown field specifica‐
tions.
When eviction is not enabled, via overflow_policy or an OpenFlow
1.4+ ``table mod,’’ this column has no effect.
Classifier Optimization:
prefixes: set of up to 3 strings
This string set specifies which fields should be used for ad‐
dress prefix tracking. Prefix tracking allows the classifier to
skip rules with longer than necessary prefixes, resulting in
better wildcarding for datapath flows.
Prefix tracking may be beneficial when a flow table contains
matches on IP address fields with different prefix lengths. For
example, when a flow table contains IP address matches on both
full addresses and proper prefixes, the full address matches
will typically cause the datapath flow to un-wildcard the whole
address field (depending on flow entry priorities). In this case
each packet with a different address gets handed to the user‐
space for flow processing and generates its own datapath flow.
With prefix tracking enabled for the address field in question
packets with addresses matching shorter prefixes would generate
datapath flows where the irrelevant address bits are wildcarded,
allowing the same datapath flow to handle all the packets within
the prefix in question. In this case many userspace upcalls can
be avoided and the overall performance can be better.
This is a performance optimization only, so packets will receive
the same treatment with or without prefix tracking.
The supported fields are: tun_id, tun_src, tun_dst,
tun_ipv6_src, tun_ipv6_dst, nw_src, nw_dst (or aliases ip_src
and ip_dst), ipv6_src, and ipv6_dst. (Using this feature for
tun_id would only make sense if the tunnel IDs have prefix
structure similar to IP addresses.)
By default, the prefixes=ip_dst,ip_src are used on each flow ta‐
ble. This instructs the flow classifier to track the IP destina‐
tion and source addresses used by the rules in this specific
flow table.
The keyword none is recognized as an explicit override of the
default values, causing no prefix fields to be tracked.
To set the prefix fields, the flow table record needs to exist:
ovs-vsctl set Bridge br0 flow_tables:0=@N1 -- --id=@N1 create
Flow_Table name=table0
Creates a flow table record for the OpenFlow table number
0.
ovs-vsctl set Flow_Table table0 prefixes=ip_dst,ip_src
Enables prefix tracking for IP source and destination ad‐
dress fields.
There is a maximum number of fields that can be enabled for any
one flow table. Currently this limit is 3.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
external_ids: map of string-string pairs
QoS TABLE
Quality of Service (QoS) configuration for each Port that references
it.
Summary:
type string
queues map of integer-Queue pairs, key in range
0 to 4,294,967,295
Configuration for linux-htb and linux-hfsc:
other_config : max-rate optional string, containing an integer
Configuration for egress-policer QoS:
other_config : cir optional string, containing an integer
other_config : cbs optional string, containing an integer
other_config : eir optional string, containing an integer
other_config : ebs optional string, containing an integer
Configuration for linux-sfq:
other_config : perturb optional string, containing an integer
other_config : quantum optional string, containing an integer
Configuration for linux-netem:
other_config : latency optional string, containing an integer
other_config : limit optional string, containing an integer
other_config : loss optional string, containing an integer
other_config : jitter optional string, containing an integer
Common Columns:
other_config map of string-string pairs
external_ids map of string-string pairs
Details:
type: string
The type of QoS to implement. The currently defined types are
listed below:
linux-htb
Linux ``hierarchy token bucket’’ classifier. See tc-
htb(8) (also at http://linux.die.net/man/8/tc-htb) and
the HTB manual (http://luxik.cdi.cz/~devik/qos/htb/man‐
ual/userg.htm) for information on how this classifier
works and how to configure it.
linux-hfsc
Linux "Hierarchical Fair Service Curve" classifier. See
http://linux-ip.net/articles/hfsc.en/ for information on
how this classifier works.
linux-sfq
Linux ``Stochastic Fairness Queueing’’ classifier. See
tc-sfq(8) (also at http://linux.die.net/man/8/tc-sfq) for
information on how this classifier works.
linux-codel
Linux ``Controlled Delay’’ classifier. See tc-codel(8)
(also at
http://man7.org/linux/man-pages/man8/tc-codel.8.html) for
information on how this classifier works.
linux-fq_codel
Linux ``Fair Queuing with Controlled Delay’’ classifier.
See tc-fq_codel(8) (also at
http://man7.org/linux/man-pages/man8/tc-fq_codel.8.html)
for information on how this classifier works.
linux-netem
Linux ``Network Emulator’’ classifier. See tc-netem(8)
(also at
http://man7.org/linux/man-pages/man8/tc-netem.8.html) for
information on how this classifier works.
linux-noop
Linux ``No operation.’’ By default, Open vSwitch manages
quality of service on all of its configured ports. This
can be helpful, but sometimes administrators prefer to
use other software to manage QoS. This type prevents Open
vSwitch from changing the QoS configuration for a port.
egress-policer
A DPDK egress policer algorithm using the DPDK rte_meter
library. The rte_meter library provides an implementation
which allows the metering and policing of traffic. The
implementation in OVS essentially creates a single token
bucket used to police traffic. It should be noted that
when the rte_meter is configured as part of QoS there
will be a performance overhead as the rte_meter itself
will consume CPU cycles in order to police traffic. These
CPU cycles ordinarily are used for packet proccessing. As
such the drop in performance will be noticed in terms of
overall aggregate traffic throughput.
trtcm-policer
A DPDK egress policer algorithm using RFC 4115’s Two-
Rate, Three-Color marker. It’s a two-level hierarchical
policer which first does a color-blind marking of the
traffic at the queue level, followed by a color-aware
marking at the port level. At the end traffic marked as
Green or Yellow is forwarded, Red is dropped. For details
on how traffic is marked, see RFC 4115. If the ``default
queue’’, 0, is not configured it’s automatically created
with the same other_config values as the physical port.
queues: map of integer-Queue pairs, key in range 0 to 4,294,967,295
A map from queue numbers to Queue records. The supported range
of queue numbers depend on type. The queue numbers are the same
as the queue_id used in OpenFlow in struct ofp_action_enqueue
and other structures.
Queue 0 is the ``default queue.’’ It is used by OpenFlow output
actions when no specific queue has been set. When no configura‐
tion for queue 0 is present, it is automatically configured as
if a Queue record with empty dscp and other_config columns had
been specified. (Before version 1.6, Open vSwitch would leave
queue 0 unconfigured in this case. With some queuing disci‐
plines, this dropped all packets destined for the default
queue.)
Configuration for linux-htb and linux-hfsc:
The linux-htb and linux-hfsc classes support the following key-value
pair:
other_config : max-rate: optional string, containing an integer
Maximum rate shared by all queued traffic, in bit/s. Optional.
If not specified, for physical interfaces, the default is the
link rate. For other interfaces or if the link rate cannot be
determined, the default is currently 10 Gbps.
Configuration for egress-policer QoS:
QoS type egress-policer provides egress policing for userspace port
types with DPDK. It has the following key-value pairs defined.
other_config : cir: optional string, containing an integer
The Committed Information Rate (CIR) is measured in bytes of IP
packets per second, i.e. it includes the IP header, but not link
specific (e.g. Ethernet) headers. This represents the bytes per
second rate at which the token bucket will be updated. The cir
value is calculated by (pps x packet data size). For example as‐
suming a user wishes to limit a stream consisting of 64 byte
packets to 1 million packets per second the CIR would be set to
to to 46000000. This value can be broken into ’1,000,000 x 46’.
Where 1,000,000 is the policing rate for the number of packets
per second and 46 represents the size of the packet data for a
64 bytes IP packet without 14 bytes Ethernet and 4 bytes FCS
header.
other_config : cbs: optional string, containing an integer
The Committed Burst Size (CBS) is measured in bytes and repre‐
sents a token bucket. At a minimum this value should be be set
to the expected largest size packet in the traffic stream. In
practice larger values may be used to increase the size of the
token bucket. If a packet can be transmitted then the cbs will
be decremented by the number of bytes/tokens of the packet. If
there are not enough tokens in the cbs bucket the packet will be
dropped.
other_config : eir: optional string, containing an integer
The Excess Information Rate (EIR) is measured in bytes of IP
packets per second, i.e. it includes the IP header, but not link
specific (e.g. Ethernet) headers. This represents the bytes per
second rate at which the token bucket will be updated. The eir
value is calculated by (pps x packet data size). For example as‐
suming a user wishes to limit a stream consisting of 64 byte
packets to 1 million packets per second the EIR would be set to
to to 46000000. This value can be broken into ’1,000,000 x 46’.
Where 1,000,000 is the policing rate for the number of packets
per second and 46 represents the size of the packet data for a
64 bytes IP packet without 14 bytes Ethernet and 4 bytes FCS
header.
other_config : ebs: optional string, containing an integer
The Excess Burst Size (EBS) is measured in bytes and represents
a token bucket. At a minimum this value should be be set to the
expected largest size packet in the traffic stream. In practice
larger values may be used to increase the size of the token
bucket. If a packet can be transmitted then the ebs will be
decremented by the number of bytes/tokens of the packet. If
there are not enough tokens in the cbs bucket the packet might
be dropped.
Configuration for linux-sfq:
The linux-sfq QoS supports the following key-value pairs:
other_config : perturb: optional string, containing an integer
Number of seconds between consecutive perturbations in hashing
algorithm. Different flows can end up in the same hash bucket
causing unfairness. Perturbation’s goal is to remove possible
unfairness. The default and recommended value is 10. Too low a
value is discouraged because each perturbation can cause packet
reordering.
other_config : quantum: optional string, containing an integer
Number of bytes linux-sfq QoS can dequeue in one turn in round-
robin from one flow. The default and recommended value is equal
to interface’s MTU.
Configuration for linux-netem:
The linux-netem QoS supports the following key-value pairs:
other_config : latency: optional string, containing an integer
Adds the chosen delay to the packets outgoing to chosen network
interface. The latency value expressed in us.
other_config : limit: optional string, containing an integer
Maximum number of packets the qdisc may hold queued at a time.
The default value is 1000.
other_config : loss: optional string, containing an integer
Adds an independent loss probability to the packets outgoing
from the chosen network interface.
other_config : jitter: optional string, containing an integer
Adds the provided jitter to the latency outgoing to the chosen
network interface. The jitter value expressed in us.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
other_config: map of string-string pairs
external_ids: map of string-string pairs
Queue TABLE
A configuration for a port output queue, used in configuring Quality of
Service (QoS) features. May be referenced by queues column in QoS ta‐
ble.
Summary:
dscp optional integer, in range 0 to 63
Configuration for linux-htb QoS:
other_config : min-rate optional string, containing an integer,
at least 1
other_config : max-rate optional string, containing an integer,
at least 1
other_config : burst optional string, containing an integer,
at least 1
other_config : priority optional string, containing an integer,
in range 0 to 4,294,967,295
Configuration for linux-hfsc QoS:
other_config : min-rate optional string, containing an integer,
at least 1
other_config : max-rate optional string, containing an integer,
at least 1
Common Columns:
other_config map of string-string pairs
external_ids map of string-string pairs
Details:
dscp: optional integer, in range 0 to 63
If set, Open vSwitch will mark all traffic egressing this Queue
with the given DSCP bits. Traffic egressing the default Queue is
only marked if it was explicitly selected as the Queue at the
time the packet was output. If unset, the DSCP bits of traffic
egressing this Queue will remain unchanged.
Configuration for linux-htb QoS:
QoS type linux-htb may use queue_ids less than 61440. It has the fol‐
lowing key-value pairs defined.
other_config : min-rate: optional string, containing an integer, at
least 1
Minimum guaranteed bandwidth, in bit/s.
other_config : max-rate: optional string, containing an integer, at
least 1
Maximum allowed bandwidth, in bit/s. Optional. If specified, the
queue’s rate will not be allowed to exceed the specified value,
even if excess bandwidth is available. If unspecified, defaults
to no limit.
other_config : burst: optional string, containing an integer, at least
1
Burst size, in bits. This is the maximum amount of ``credits’’
that a queue can accumulate while it is idle. Optional. Details
of the linux-htb implementation require a minimum burst size, so
a too-small burst will be silently ignored.
other_config : priority: optional string, containing an integer, in
range 0 to 4,294,967,295
A queue with a smaller priority will receive all the excess
bandwidth that it can use before a queue with a larger value re‐
ceives any. Specific priority values are unimportant; only rela‐
tive ordering matters. Defaults to 0 if unspecified.
Configuration for linux-hfsc QoS:
QoS type linux-hfsc may use queue_ids less than 61440. It has the fol‐
lowing key-value pairs defined.
other_config : min-rate: optional string, containing an integer, at
least 1
Minimum guaranteed bandwidth, in bit/s.
other_config : max-rate: optional string, containing an integer, at
least 1
Maximum allowed bandwidth, in bit/s. Optional. If specified, the
queue’s rate will not be allowed to exceed the specified value,
even if excess bandwidth is available. If unspecified, defaults
to no limit.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
other_config: map of string-string pairs
external_ids: map of string-string pairs
Mirror TABLE
A port mirror within a Bridge.
A port mirror configures a bridge to send selected frames to special
``mirrored’’ ports, in addition to their normal destinations. Mirroring
traffic may also be referred to as SPAN or RSPAN, depending on how the
mirrored traffic is sent.
When a packet enters an Open vSwitch bridge, it becomes eligible for
mirroring based on its ingress port and VLAN. As the packet travels
through the flow tables, each time it is output to a port, it becomes
eligible for mirroring based on the egress port and VLAN. In Open
vSwitch 2.5 and later, mirroring occurs just after a packet first be‐
comes eligible, using the packet as it exists at that point; in Open
vSwitch 2.4 and earlier, mirroring occurs only after a packet has tra‐
versed all the flow tables, using the original packet as it entered the
bridge. This makes a difference only when the flow table modifies the
packet: in Open vSwitch 2.4, the modifications are never visible to
mirrors, whereas in Open vSwitch 2.5 and later modifications made be‐
fore the first output that makes it eligible for mirroring to a partic‐
ular destination are visible.
A packet that enters an Open vSwitch bridge is mirrored to a particular
destination only once, even if it is eligible for multiple reasons. For
example, a packet would be mirrored to a particular output_port only
once, even if it is selected for mirroring to that port by se‐
lect_dst_port and select_src_port in the same or different Mirror
records.
Summary:
name string
Selecting Packets for Mirroring:
select_all boolean
select_dst_port set of weak reference to Ports
select_src_port set of weak reference to Ports
select_vlan set of up to 4,096 integers, in range 0
to 4,095
filter optional string
Mirroring Destination Configuration:
output_port optional weak reference to Port
output_vlan optional integer, in range 1 to 4,095
snaplen optional integer, in range 14 to 65,535
Statistics: Mirror counters:
statistics : tx_packets optional integer
statistics : tx_bytes optional integer
Common Columns:
external_ids map of string-string pairs
Details:
name: string
Arbitrary identifier for the Mirror.
Selecting Packets for Mirroring:
To be selected for mirroring, a given packet must enter or leave the
bridge through a selected port and it must also be in one of the se‐
lected VLANs.
select_all: boolean
If true, every packet arriving or departing on any port is se‐
lected for mirroring.
select_dst_port: set of weak reference to Ports
Ports on which departing packets are selected for mirroring.
select_src_port: set of weak reference to Ports
Ports on which arriving packets are selected for mirroring.
select_vlan: set of up to 4,096 integers, in range 0 to 4,095
VLANs on which packets are selected for mirroring. An empty set
selects packets on all VLANs.
filter: optional string
When set, only packets that match filter are selected for mir‐
roring. Packets that do not match are ignored by thie mirror.
The filter syntax is described in ovs-fields(7). However, the
in_port field is not supported; select_src_port should be used
to limit the mirror to a source port.
This filter is applied after select_all, select_dst_port, se‐
lect_src_port, and select_vlan.
Mirroring Destination Configuration:
These columns are mutually exclusive. Exactly one of them must be non‐
empty.
output_port: optional weak reference to Port
Output port for selected packets, if nonempty.
Specifying a port for mirror output reserves that port exclu‐
sively for mirroring. No frames other than those selected for
mirroring via this column will be forwarded to the port, and any
frames received on the port will be discarded.
The output port may be any kind of port supported by Open
vSwitch. It may be, for example, a physical port (sometimes
called SPAN) or a GRE tunnel.
output_vlan: optional integer, in range 1 to 4,095
Output VLAN for selected packets, if nonempty.
The frames will be sent out all ports that trunk output_vlan, as
well as any ports with implicit VLAN output_vlan. When a mir‐
rored frame is sent out a trunk port, the frame’s VLAN tag will
be set to output_vlan, replacing any existing tag; when it is
sent out an implicit VLAN port, the frame will not be tagged.
This type of mirroring is sometimes called RSPAN.
See the documentation for other_config:forward-bpdu in the In‐
terface table for a list of destination MAC addresses which will
not be mirrored to a VLAN to avoid confusing switches that in‐
terpret the protocols that they represent.
Please note: Mirroring to a VLAN can disrupt a network that con‐
tains unmanaged switches. Consider an unmanaged physical switch
with two ports: port 1, connected to an end host, and port 2,
connected to an Open vSwitch configured to mirror received pack‐
ets into VLAN 123 on port 2. Suppose that the end host sends a
packet on port 1 that the physical switch forwards to port 2.
The Open vSwitch forwards this packet to its destination and
then reflects it back on port 2 in VLAN 123. This reflected
packet causes the unmanaged physical switch to replace the MAC
learning table entry, which correctly pointed to port 1, with
one that incorrectly points to port 2. Afterward, the physical
switch will direct packets destined for the end host to the Open
vSwitch on port 2, instead of to the end host on port 1, dis‐
rupting connectivity. If mirroring to a VLAN is desired in this
scenario, then the physical switch must be replaced by one that
learns Ethernet addresses on a per-VLAN basis. In addition,
learning should be disabled on the VLAN containing mirrored
traffic. If this is not done then intermediate switches will
learn the MAC address of each end host from the mirrored traf‐
fic. If packets being sent to that end host are also mirrored,
then they will be dropped since the switch will attempt to send
them out the input port. Disabling learning for the VLAN will
cause the switch to correctly send the packet out all ports con‐
figured for that VLAN. If Open vSwitch is being used as an in‐
termediate switch, learning can be disabled by adding the mir‐
rored VLAN to flood_vlans in the appropriate Bridge table or ta‐
bles.
Mirroring to a GRE tunnel has fewer caveats than mirroring to a
VLAN and should generally be preferred.
snaplen: optional integer, in range 14 to 65,535
Maximum per-packet number of bytes to mirror.
A mirrored packet with size larger than snaplen will be trun‐
cated in datapath to snaplen bytes before sending to the mirror
output port. If omitted, packets are not truncated.
Statistics: Mirror counters:
Key-value pairs that report mirror statistics. The update period is
controlled by other_config:stats-update-interval in the Open_vSwitch
table.
statistics : tx_packets: optional integer
Number of packets transmitted through this mirror.
statistics : tx_bytes: optional integer
Number of bytes transmitted through this mirror.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
external_ids: map of string-string pairs
Controller TABLE
An OpenFlow controller.
Summary:
Core Features:
type optional string, either primary or ser‐
vice
target string
connection_mode optional string, either in-band or
out-of-band
Controller Failure Detection and Handling:
max_backoff optional integer, at least 1,000
inactivity_probe optional integer
Asynchronous Messages:
enable_async_messages optional boolean
Controller Rate Limiting:
controller_queue_size optional integer, in range 1 to 512
controller_rate_limit optional integer, at least 100
controller_burst_limit optional integer, at least 25
Controller Rate Limiting Statistics:
status : packet-in-TYPE-bypassed
optional string, containing an integer,
at least 0
status : packet-in-TYPE-queued
optional string, containing an integer,
at least 0
status : packet-in-TYPE-dropped
optional string, containing an integer,
at least 0
status : packet-in-TYPE-backlog
optional string, containing an integer,
at least 0
Additional In-Band Configuration:
local_ip optional string
local_netmask optional string
local_gateway optional string
Controller Status:
is_connected boolean
role optional string, one of master, other, or
slave
status : last_error optional string
status : state optional string, one of ACTIVE, BACKOFF,
CONNECTING, IDLE, or VOID
status : sec_since_connect optional string, containing an integer,
at least 0
status : sec_since_disconnect
optional string, containing an integer,
at least 1
Connection Parameters:
other_config : dscp optional string, containing an integer
Common Columns:
external_ids map of string-string pairs
other_config map of string-string pairs
Details:
Core Features:
type: optional string, either primary or service
Open vSwitch supports two kinds of OpenFlow controllers. A
bridge may have any number of each kind:
Primary controllers
This is the kind of controller envisioned by the OpenFlow
specifications. Usually, a primary controller implements
a network policy by taking charge of the switch’s flow
table.
The fail_mode column in the Bridge table applies to pri‐
mary controllers.
When multiple primary controllers are configured, Open
vSwitch connects to all of them simultaneously. OpenFlow
provides few facilities to allow multiple controllers to
coordinate in interacting with a single switch, so more
than one primary controller should be specified only if
the controllers are themselves designed to coordinate
with each other.
Service controllers
These kinds of OpenFlow controller connections are in‐
tended for occasional support and maintenance use, e.g.
with ovs-ofctl. Usually a service controller connects
only briefly to inspect or modify some of a switch’s
state.
The fail_mode column in the Bridge table does not apply
to service controllers.
By default, Open vSwitch treats controllers with active connec‐
tion methods as primary controllers and those with passive con‐
nection methods as service controllers. Set this column to the
desired type to override this default.
target: string
Connection method for controller.
The following active connection methods are currently supported:
ssl:host[:port]
The specified SSL port on the host at the given host,
which can either be a DNS name (if built with unbound li‐
brary) or an IP address. The ssl column in the
Open_vSwitch table must point to a valid SSL configura‐
tion when this form is used.
If port is not specified, it defaults to 6653.
SSL support is an optional feature that is not always
built as part of Open vSwitch.
tcp:host[:port]
The specified TCP port on the host at the given host,
which can either be a DNS name (if built with unbound li‐
brary) or an IP address (IPv4 or IPv6). If host is an
IPv6 address, wrap it in square brackets, e.g.
tcp:[::1]:6653.
If port is not specified, it defaults to 6653.
The following passive connection methods are currently sup‐
ported:
pssl:[port][:host]
Listens for SSL connections on the specified TCP port. If
host, which can either be a DNS name (if built with un‐
bound library) or an IP address, is specified, then con‐
nections are restricted to the resolved or specified lo‐
cal IP address (either IPv4 or IPv6). If host is an IPv6
address, wrap it in square brackets, e.g.
pssl:6653:[::1].
If port is not specified, it defaults to 6653. If host is
not specified then it listens only on IPv4 (but not IPv6)
addresses. The ssl column in the Open_vSwitch table must
point to a valid SSL configuration when this form is
used.
If port is not specified, it currently to 6653.
SSL support is an optional feature that is not always
built as part of Open vSwitch.
ptcp:[port][:host]
Listens for connections on the specified TCP port. If
host, which can either be a DNS name (if built with un‐
bound library) or an IP address, is specified, then con‐
nections are restricted to the resolved or specified lo‐
cal IP address (either IPv4 or IPv6). If host is an IPv6
address, wrap it in square brackets, e.g.
ptcp:6653:[::1]. If host is not specified then it listens
only on IPv4 addresses.
If port is not specified, it defaults to 6653.
When multiple controllers are configured for a single bridge,
the target values must be unique. Duplicate target values yield
unspecified results.
connection_mode: optional string, either in-band or out-of-band
If it is specified, this setting must be one of the following
strings that describes how Open vSwitch contacts this OpenFlow
controller over the network:
in-band
In this mode, this controller’s OpenFlow traffic travels
over the bridge associated with the controller. With this
setting, Open vSwitch allows traffic to and from the con‐
troller regardless of the contents of the OpenFlow flow
table. (Otherwise, Open vSwitch would never be able to
connect to the controller, because it did not have a flow
to enable it.) This is the most common connection mode
because it is not necessary to maintain two independent
networks.
out-of-band
In this mode, OpenFlow traffic uses a control network
separate from the bridge associated with this controller,
that is, the bridge does not use any of its own network
devices to communicate with the controller. The control
network must be configured separately, before or after
ovs-vswitchd is started.
If not specified, the default is implementation-specific.
Controller Failure Detection and Handling:
max_backoff: optional integer, at least 1,000
Maximum number of milliseconds to wait between connection at‐
tempts. Default is implementation-specific.
inactivity_probe: optional integer
Maximum number of milliseconds of idle time on connection to
controller before sending an inactivity probe message. If Open
vSwitch does not communicate with the controller for the speci‐
fied number of seconds, it will send a probe. If a response is
not received for the same additional amount of time, Open
vSwitch assumes the connection has been broken and attempts to
reconnect. Default is implementation-specific. A value of 0 dis‐
ables inactivity probes.
Asynchronous Messages:
OpenFlow switches send certain messages to controllers spontanenously,
that is, not in response to any request from the controller. These mes‐
sages are called ``asynchronous messages.’’ These columns allow asyn‐
chronous messages to be limited or disabled to ensure the best use of
network resources.
enable_async_messages: optional boolean
The OpenFlow protocol enables asynchronous messages at time of
connection establishment, which means that a controller can re‐
ceive asynchronous messages, potentially many of them, even if
it turns them off immediately after connecting. Set this column
to false to change Open vSwitch behavior to disable, by default,
all asynchronous messages. The controller can use the
NXT_SET_ASYNC_CONFIG Nicira extension to OpenFlow to turn on any
messages that it does want to receive, if any.
Controller Rate Limiting:
A switch can forward packets to a controller over the OpenFlow proto‐
col. Forwarding packets this way at too high a rate can overwhelm a
controller, frustrate use of the OpenFlow connection for other pur‐
poses, increase the latency of flow setup, and use an unreasonable
amount of bandwidth. Therefore, Open vSwitch supports limiting the rate
of packet forwarding to a controller.
There are two main reasons in OpenFlow for a packet to be sent to a
controller: either the packet ``misses’’ in the flow table, that is,
there is no matching flow, or a flow table action says to send the
packet to the controller. Open vSwitch limits the rate of each kind of
packet separately at the configured rate. Therefore, the actual rate
that packets are sent to the controller can be up to twice the config‐
ured rate, when packets are sent for both reasons.
This feature is specific to forwarding packets over an OpenFlow connec‐
tion. It is not general-purpose QoS. See the QoS table for quality of
service configuration, and ingress_policing_rate in the Interface table
for ingress policing configuration.
controller_queue_size: optional integer, in range 1 to 512
This sets the maximum size of the queue of packets that need to
be sent to this OpenFlow controller. The value must be less than
512. If not specified the queue size is limited to the value set
for the management controller in other_config:controller-queue-
size if present or 100 packets by default. Note: increasing the
queue size might have a negative impact on latency.
controller_rate_limit: optional integer, at least 100
The maximum rate at which the switch will forward packets to the
OpenFlow controller, in packets per second. If no value is spec‐
ified, rate limiting is disabled.
controller_burst_limit: optional integer, at least 25
When a high rate triggers rate-limiting, Open vSwitch queues
packets to the controller for each port and transmits them to
the controller at the configured rate. This value limits the
number of queued packets. Ports on a bridge share the packet
queue fairly.
This value has no effect unless controller_rate_limit is config‐
ured. The current default when this value is not specified is
one-quarter of controller_rate_limit, meaning that queuing can
delay forwarding a packet to the controller by up to 250 ms.
Controller Rate Limiting Statistics:
These values report the effects of rate limiting. Their values are rel‐
ative to establishment of the most recent OpenFlow connection, or since
rate limiting was enabled, whichever happened more recently. Each con‐
sists of two values, one with TYPE replaced by miss for rate limiting
flow table misses, and the other with TYPE replaced by action for rate
limiting packets sent by OpenFlow actions.
These statistics are reported only when controller rate limiting is en‐
abled.
status : packet-in-TYPE-bypassed: optional string, containing an inte‐
ger, at least 0
Number of packets sent directly to the controller, without queu‐
ing, because the rate did not exceed the configured maximum.
status : packet-in-TYPE-queued: optional string, containing an integer,
at least 0
Number of packets added to the queue to send later.
status : packet-in-TYPE-dropped: optional string, containing an inte‐
ger, at least 0
Number of packets added to the queue that were later dropped due
to overflow. This value is less than or equal to status:packet-
in-TYPE-queued.
status : packet-in-TYPE-backlog: optional string, containing an inte‐
ger, at least 0
Number of packets currently queued. The other statistics in‐
crease monotonically, but this one fluctuates between 0 and the
controller_burst_limit as conditions change.
Additional In-Band Configuration:
These values are considered only in in-band control mode (see connec‐
tion_mode).
When multiple controllers are configured on a single bridge, there
should be only one set of unique values in these columns. If different
values are set for these columns in different controllers, the effect
is unspecified.
local_ip: optional string
The IP address to configure on the local port, e.g.
192.168.0.123. If this value is unset, then local_netmask and
local_gateway are ignored.
local_netmask: optional string
The IP netmask to configure on the local port, e.g.
255.255.255.0. If local_ip is set but this value is unset, then
the default is chosen based on whether the IP address is class
A, B, or C.
local_gateway: optional string
The IP address of the gateway to configure on the local port, as
a string, e.g. 192.168.0.1. Leave this column unset if this net‐
work has no gateway.
Controller Status:
is_connected: boolean
true if currently connected to this controller, false otherwise.
role: optional string, one of master, other, or slave
The level of authority this controller has on the associated
bridge. Possible values are:
other Allows the controller access to all OpenFlow features.
master Equivalent to other, except that there may be at most one
such controller at a time. If a given controller promotes
itself to this role, ovs-vswitchd demotes any existing
controller with the role to slave.
slave Allows the controller read-only access to OpenFlow fea‐
tures. Attempts to modify the flow table will be rejected
with an error. Such controllers do not receive
OFPT_PACKET_IN or OFPT_FLOW_REMOVED messages, but they do
receive OFPT_PORT_STATUS messages.
status : last_error: optional string
A human-readable description of the last error on the connection
to the controller; i.e. strerror(errno). This key will exist
only if an error has occurred.
status : state: optional string, one of ACTIVE, BACKOFF, CONNECTING,
IDLE, or VOID
The state of the connection to the controller:
VOID Connection is disabled.
BACKOFF
Attempting to reconnect at an increasing period.
CONNECTING
Attempting to connect.
ACTIVE Connected, remote host responsive.
IDLE Connection is idle. Waiting for response to keep-alive.
These values may change in the future. They are provided only
for human consumption.
status : sec_since_connect: optional string, containing an integer, at
least 0
The amount of time since this controller last successfully con‐
nected to the switch (in seconds). Value is empty if controller
has never successfully connected.
status : sec_since_disconnect: optional string, containing an integer,
at least 1
The amount of time since this controller last disconnected from
the switch (in seconds). Value is empty if controller has never
disconnected.
Connection Parameters:
Additional configuration for a connection between the controller and
the Open vSwitch.
other_config : dscp: optional string, containing an integer
The Differentiated Service Code Point (DSCP) is specified using
6 bits in the Type of Service (TOS) field in the IP header. DSCP
provides a mechanism to classify the network traffic and provide
Quality of Service (QoS) on IP networks. The DSCP value speci‐
fied here is used when establishing the connection between the
controller and the Open vSwitch. If no value is specified, a de‐
fault value of 48 is chosen. Valid DSCP values must be in the
range 0 to 63.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
external_ids: map of string-string pairs
other_config: map of string-string pairs
Manager TABLE
Configuration for a database connection to an Open vSwitch database
(OVSDB) client.
This table primarily configures the Open vSwitch database
(ovsdb-server), not the Open vSwitch switch (ovs-vswitchd). The switch
does read the table to determine what connections should be treated as
in-band.
The Open vSwitch database server can initiate and maintain active con‐
nections to remote clients. It can also listen for database connec‐
tions.
Summary:
Core Features:
target string (must be unique within table)
connection_mode optional string, either in-band or
out-of-band
Client Failure Detection and Handling:
max_backoff optional integer, at least 1,000
inactivity_probe optional integer
Status:
is_connected boolean
status : last_error optional string
status : state optional string, one of ACTIVE, BACKOFF,
CONNECTING, IDLE, or VOID
status : sec_since_connect optional string, containing an integer,
at least 0
status : sec_since_disconnect
optional string, containing an integer,
at least 0
status : locks_held optional string
status : locks_waiting optional string
status : locks_lost optional string
status : n_connections optional string, containing an integer,
at least 2
status : bound_port optional string, containing an integer
Connection Parameters:
other_config : dscp optional string, containing an integer
Common Columns:
external_ids map of string-string pairs
other_config map of string-string pairs
Details:
Core Features:
target: string (must be unique within table)
Connection method for managers.
The following connection methods are currently supported:
ssl:host[:port]
The specified SSL port on the host at the given host,
which can either be a DNS name (if built with unbound li‐
brary) or an IP address. The ssl column in the
Open_vSwitch table must point to a valid SSL configura‐
tion when this form is used.
If port is not specified, it defaults to 6640.
SSL support is an optional feature that is not always
built as part of Open vSwitch.
tcp:host[:port]
The specified TCP port on the host at the given host,
which can either be a DNS name (if built with unbound li‐
brary) or an IP address (IPv4 or IPv6). If host is an
IPv6 address, wrap it in square brackets, e.g.
tcp:[::1]:6640.
If port is not specified, it defaults to 6640.
pssl:[port][:host]
Listens for SSL connections on the specified TCP port.
Specify 0 for port to have the kernel automatically
choose an available port. If host, which can either be a
DNS name (if built with unbound library) or an IP ad‐
dress, is specified, then connections are restricted to
the resolved or specified local IP address (either IPv4
or IPv6 address). If host is an IPv6 address, wrap in
square brackets, e.g. pssl:6640:[::1]. If host is not
specified then it listens only on IPv4 (but not IPv6) ad‐
dresses. The ssl column in the Open_vSwitch table must
point to a valid SSL configuration when this form is
used.
If port is not specified, it defaults to 6640.
SSL support is an optional feature that is not always
built as part of Open vSwitch.
ptcp:[port][:host]
Listens for connections on the specified TCP port. Spec‐
ify 0 for port to have the kernel automatically choose an
available port. If host, which can either be a DNS name
(if built with unbound library) or an IP address, is
specified, then connections are restricted to the re‐
solved or specified local IP address (either IPv4 or IPv6
address). If host is an IPv6 address, wrap it in square
brackets, e.g. ptcp:6640:[::1]. If host is not specified
then it listens only on IPv4 addresses.
If port is not specified, it defaults to 6640.
When multiple managers are configured, the target values must be
unique. Duplicate target values yield unspecified results.
connection_mode: optional string, either in-band or out-of-band
If it is specified, this setting must be one of the following
strings that describes how Open vSwitch contacts this OVSDB
client over the network:
in-band
In this mode, this connection’s traffic travels over a
bridge managed by Open vSwitch. With this setting, Open
vSwitch allows traffic to and from the client regardless
of the contents of the OpenFlow flow table. (Otherwise,
Open vSwitch would never be able to connect to the
client, because it did not have a flow to enable it.)
This is the most common connection mode because it is not
necessary to maintain two independent networks.
out-of-band
In this mode, the client’s traffic uses a control network
separate from that managed by Open vSwitch, that is, Open
vSwitch does not use any of its own network devices to
communicate with the client. The control network must be
configured separately, before or after ovs-vswitchd is
started.
If not specified, the default is implementation-specific.
Client Failure Detection and Handling:
max_backoff: optional integer, at least 1,000
Maximum number of milliseconds to wait between connection at‐
tempts. Default is implementation-specific.
inactivity_probe: optional integer
Maximum number of milliseconds of idle time on connection to the
client before sending an inactivity probe message. If Open
vSwitch does not communicate with the client for the specified
number of seconds, it will send a probe. If a response is not
received for the same additional amount of time, Open vSwitch
assumes the connection has been broken and attempts to recon‐
nect. Default is implementation-specific. A value of 0 disables
inactivity probes.
Status:
Key-value pair of is_connected is always updated. Other key-value pairs
in the status columns may be updated depends on the target type.
When target specifies a connection method that listens for inbound con‐
nections (e.g. ptcp: or punix:), both n_connections and is_connected
may also be updated while the remaining key-value pairs are omitted.
On the other hand, when target specifies an outbound connection, all
key-value pairs may be updated, except the above-mentioned two key-
value pairs associated with inbound connection targets. They are omit‐
ted.
is_connected: boolean
true if currently connected to this manager, false otherwise.
status : last_error: optional string
A human-readable description of the last error on the connection
to the manager; i.e. strerror(errno). This key will exist only
if an error has occurred.
status : state: optional string, one of ACTIVE, BACKOFF, CONNECTING,
IDLE, or VOID
The state of the connection to the manager:
VOID Connection is disabled.
BACKOFF
Attempting to reconnect at an increasing period.
CONNECTING
Attempting to connect.
ACTIVE Connected, remote host responsive.
IDLE Connection is idle. Waiting for response to keep-alive.
These values may change in the future. They are provided only
for human consumption.
status : sec_since_connect: optional string, containing an integer, at
least 0
The amount of time since this manager last successfully con‐
nected to the database (in seconds). Value is empty if manager
has never successfully connected.
status : sec_since_disconnect: optional string, containing an integer,
at least 0
The amount of time since this manager last disconnected from the
database (in seconds). Value is empty if manager has never dis‐
connected.
status : locks_held: optional string
Space-separated list of the names of OVSDB locks that the con‐
nection holds. Omitted if the connection does not hold any
locks.
status : locks_waiting: optional string
Space-separated list of the names of OVSDB locks that the con‐
nection is currently waiting to acquire. Omitted if the connec‐
tion is not waiting for any locks.
status : locks_lost: optional string
Space-separated list of the names of OVSDB locks that the con‐
nection has had stolen by another OVSDB client. Omitted if no
locks have been stolen from this connection.
status : n_connections: optional string, containing an integer, at
least 2
When target specifies a connection method that listens for in‐
bound connections (e.g. ptcp: or pssl:) and more than one con‐
nection is actually active, the value is the number of active
connections. Otherwise, this key-value pair is omitted.
status : bound_port: optional string, containing an integer
When target is ptcp: or pssl:, this is the TCP port on which the
OVSDB server is listening. (This is particularly useful when
target specifies a port of 0, allowing the kernel to choose any
available port.)
Connection Parameters:
Additional configuration for a connection between the manager and the
Open vSwitch Database.
other_config : dscp: optional string, containing an integer
The Differentiated Service Code Point (DSCP) is specified using
6 bits in the Type of Service (TOS) field in the IP header. DSCP
provides a mechanism to classify the network traffic and provide
Quality of Service (QoS) on IP networks. The DSCP value speci‐
fied here is used when establishing the connection between the
manager and the Open vSwitch. If no value is specified, a de‐
fault value of 48 is chosen. Valid DSCP values must be in the
range 0 to 63.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
external_ids: map of string-string pairs
other_config: map of string-string pairs
NetFlow TABLE
A NetFlow target. NetFlow is a protocol that exports a number of de‐
tails about terminating IP flows, such as the principals involved and
duration.
Summary:
targets set of 1 or more strings
engine_id optional integer, in range 0 to 255
engine_type optional integer, in range 0 to 255
active_timeout integer, at least -1
add_id_to_interface boolean
Common Columns:
external_ids map of string-string pairs
Details:
targets: set of 1 or more strings
NetFlow targets in the form ip:port. The ip must be specified
numerically, not as a DNS name.
engine_id: optional integer, in range 0 to 255
Engine ID to use in NetFlow messages. Defaults to datapath index
if not specified.
engine_type: optional integer, in range 0 to 255
Engine type to use in NetFlow messages. Defaults to datapath in‐
dex if not specified.
active_timeout: integer, at least -1
The interval at which NetFlow records are sent for flows that
are still active, in seconds. A value of 0 requests the default
timeout (currently 600 seconds); a value of -1 disables active
timeouts.
The NetFlow passive timeout, for flows that become inactive, is
not configurable. It will vary depending on the Open vSwitch
version, the forms and contents of the OpenFlow flow tables, CPU
and memory usage, and network activity. A typical passive time‐
out is about a second.
add_id_to_interface: boolean
If this column’s value is false, the ingress and egress inter‐
face fields of NetFlow flow records are derived from OpenFlow
port numbers. When it is true, the 7 most significant bits of
these fields will be replaced by the least significant 7 bits of
the engine id. This is useful because many NetFlow collectors do
not expect multiple switches to be sending messages from the
same host, so they do not store the engine information which
could be used to disambiguate the traffic.
When this option is enabled, a maximum of 508 ports are sup‐
ported.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
external_ids: map of string-string pairs
Datapath TABLE
Configuration for a datapath within Open_vSwitch.
A datapath is responsible for providing the packet handling in Open
vSwitch. There are two primary datapath implementations used by Open
vSwitch: kernel and userspace. Kernel datapath implementations are
available for Linux and Hyper-V, and selected as system in the data‐
path_type column of the Bridge table. The userspace datapath is used by
DPDK and AF-XDP, and is selected as netdev in the datapath_type column
of the Bridge table.
A datapath of a particular type is shared by all the bridges that use
that datapath. Thus, configurations applied to this table affect all
bridges that use this datapath.
Summary:
datapath_version string
ct_zones map of integer-CT_Zone pairs, key in
range 0 to 65,535
Capabilities:
capabilities : max_vlan_headers
optional string, containing an integer,
at least 0
capabilities : recirc optional string, either true or false
capabilities : lb_output_action
optional string, either true or false
Connection-Tracking Capabilities:
capabilities : ct_state optional string, either true or false
capabilities : ct_state_nat
optional string, either true or false
capabilities : ct_zone optional string, either true or false
capabilities : ct_mark optional string, either true or false
capabilities : ct_label optional string, either true or false
capabilities : ct_orig_tuple
optional string, either true or false
capabilities : ct_orig_tuple6
optional string, either true or false
capabilities : masked_set_action
optional string, either true or false
capabilities : tnl_push_pop
optional string, either true or false
capabilities : ufid optional string, either true or false
capabilities : trunc optional string, either true or false
capabilities : nd_ext optional string, either true or false
Clone Actions:
capabilities : clone optional string, either true or false
capabilities : sample_nesting
optional string, containing an integer,
at least 0
capabilities : ct_eventmask
optional string, either true or false
capabilities : ct_clear optional string, either true or false
capabilities : max_hash_alg
optional string, containing an integer,
at least 0
capabilities : check_pkt_len
optional string, either true or false
capabilities : ct_timeout optional string, either true or false
capabilities : explicit_drop_action
optional string, either true or false
capabilities : ct_zero_snat
optional string, either true or false
capabilities : ct_flush optional string, either true or false
capabilities : psample optional string, either true or false
ct_zone_default_limit optional integer, in range 0 to
4,294,967,295
Common Columns:
external_ids map of string-string pairs
Details:
datapath_version: string
Reports the version number of the Open vSwitch datapath in use.
This allows management software to detect and report discrepan‐
cies between Open vSwitch userspace and datapath versions. (The
ovs_version column in the Open_vSwitch reports the Open vSwitch
userspace version.) The version reported depends on the datapath
in use:
• When the kernel module included in the Open vSwitch
source tree is used, this column reports the Open vSwitch
version from which the module was taken.
• When the kernel module that is part of the upstream Linux
kernel is used, this column reports <unknown>.
• When the datapath is built into the ovs-vswitchd binary,
this column reports <built-in>. A built-in datapath is by
definition the same version as the rest of the Open
vSwitch userspace.
• Other datapaths (such as the Hyper-V kernel datapath)
currently report <unknown>.
A version discrepancy between ovs-vswitchd and the datapath in
use is not normally cause for alarm. The Open vSwitch kernel
datapaths for Linux and Hyper-V, in particular, are designed for
maximum inter-version compatibility: any userspace version works
with with any kernel version. Some reasons do exist to insist on
particular user/kernel pairings. First, newer kernel versions
add new features, that can only be used by new-enough userspace,
e.g. VXLAN tunneling requires certain minimal userspace and ker‐
nel versions. Second, as an extension to the first reason, some
newer kernel versions add new features for enhancing performance
that only new-enough userspace versions can take advantage of.
ct_zones: map of integer-CT_Zone pairs, key in range 0 to 65,535
Configuration for connection tracking zones. Each pair maps from
a zone id to a configuration for that zone. Zone 0 applies to
the default zone (ie, the one used if a zone is not specified in
connection tracking-related OpenFlow matches and actions).
Capabilities:
The capabilities column reports a datapath’s features. For the netdev
datapath, the capabilities are fixed for a given version of Open
vSwitch because this datapath is built into the ovs-vswitchd binary.
The Linux kernel and Windows and other datapaths, which are external to
OVS userspace, can vary in version and capabilities independently from
ovs-vswitchd.
Some of these features indicate whether higher-level Open vSwitch fea‐
tures are available. For example, OpenFlow features for connection-
tracking are available only when capabilities:ct_state is true. A con‐
troller that wishes to determine whether a feature is supported could,
therefore, consult the relevant capabilities in this table. However, as
a general rule, it is better for a controller to try to use the higher-
level feature and use the result as an indication of support, since the
low-level capabilities are more likely to shift over time than the
high-level features that rely on them.
capabilities : max_vlan_headers: optional string, containing an inte‐
ger, at least 0
Number of 802.1q VLAN headers supported by the datapath, as
probed by the ovs-vswitchd slow path. If the datapath supports
more VLAN headers than the slow path, this reports the slow
path’s limit. The value of other-config:vlan-limit in the
Open_vSwitch table does not influence the number reported here.
capabilities : recirc: optional string, either true or false
If this is true, then the datapath supports recirculation,
specifically OVS_KEY_ATTR_RECIRC_ID. Recirculation enables
higher performance for MPLS and active-active load balancing
bonding modes.
capabilities : lb_output_action: optional string, either true or false
If this is true, then the datapath supports optimized balance-
tcp bond mode. This capability replaces existing hash and recirc
actions with new action lb_output and avoids recirculation of
packet in datapath. It is supported only for balance-tcp bond
mode in netdev datapath. The new action gives higher performance
by using bond buckets instead of post recirculation flows for
selection of member port from bond. By default this new action
is disabled, however it can be enabled by setting other-con‐
fig:lb-output-action in Port table.
Connection-Tracking Capabilities:
These capabilities are granular because Open vSwitch and its datapaths
added support for connection tracking over several releases, with fea‐
tures added individually over that time.
capabilities : ct_state: optional string, either true or false
If true, datapath supports OVS_KEY_ATTR_CT_STATE, which indi‐
cates support for the bits in the OpenFlow ct_state field (see
ovs-fields(7)) other than snat and dnat, which have a separate
capability.
If this is false, the datapath does not support connection-
tracking at all and the remaining connection-tracking capabili‐
ties should all be false. In this case, Open vSwitch will reject
flows that match on the ct_state field or use the ct action.
capabilities : ct_state_nat: optional string, either true or false
If true, it means that the datapath supports the snat and dnat
flags in the OpenFlow ct_state field. The ct_state capability
must be true for this to make sense.
If false, Open vSwitch will reject flows that match on the snat
or dnat bits in ct_state or use nat in the ct action.
capabilities : ct_zone: optional string, either true or false
If true, datapath supports OVS_KEY_ATTR_CT_ZONE. If false, Open
vSwitch rejects flows that match on the ct_zone field or that
specify a nonzero zone or a zone field on the ct action.
capabilities : ct_mark: optional string, either true or false
If true, datapath supports OVS_KEY_ATTR_CT_MARK. If false, Open
vSwitch rejects flows that match on the ct_mark field or that
set ct_mark in the ct action.
capabilities : ct_label: optional string, either true or false
If true, datapath supports OVS_KEY_ATTR_CT_LABEL. If false, Open
vSwitch rejects flows that match on the ct_label field or that
set ct_label in the ct action.
capabilities : ct_orig_tuple: optional string, either true or false
If true, the datapath supports matching the 5-tuple from the
connection’s original direction for IPv4 traffic. If false, Open
vSwitch rejects flows that match on ct_nw_src or ct_nw_dst, that
use the ct feature of the resubmit action, or the force keyword
in the ct action. (The latter isn’t tied to connection tracking
support of original tuples in any technical way. They are con‐
flated because all current datapaths implemented the two fea‐
tures at the same time.)
If this and capabilities:ct_orig_tuple6 are both false, Open
vSwitch rejects flows that match on ct_nw_proto, ct_tp_src, or
ct_tp_dst.
capabilities : ct_orig_tuple6: optional string, either true or false
If true, the datapath supports matching the 5-tuple from the
connection’s original direction for IPv6 traffic. If false, Open
vSwitch rejects flows that match on ct_ipv6_src or ct_ipv6_dst.
capabilities : masked_set_action: optional string, either true or false
True if the datapath supports masked data in OVS_ACTION_ATTR_SET
actions. Masked data can improve performance by allowing
megaflows to match on fewer fields.
capabilities : tnl_push_pop: optional string, either true or false
True if the datapath supports tnl_push and pop actions. This is
a prerequisite for a datapath to support native tunneling.
capabilities : ufid: optional string, either true or false
True if the datapath supports OVS_FLOW_ATTR_UFID. UFID support
improves revalidation performance by transferring less data be‐
tween the slow path and the datapath.
capabilities : trunc: optional string, either true or false
True if the datapath supports OVS_ACTION_ATTR_TRUNC action. If
false, the output action with packet truncation requires every
packet to be sent to the Open vSwitch slow path, which is likely
to make it too slow for mirroring traffic in bulk.
capabilities : nd_ext: optional string, either true or false
True if the datapath supports OVS_KEY_ATTR_ND_EXTENSIONS to
match on ICMPv6 "ND reserved" and "ND option type" header
fields. If false, the datapath reports error if the feature is
used.
Clone Actions:
When Open vSwitch translates actions from OpenFlow into the datapath
representation, some of the datapath actions may modify the packet or
have other side effects that later datapath actions can’t undo. The
OpenFlow ct, meter, output with truncation, encap, decap, and
dec_nsh_ttl actions fall into this category. Often, this is not a prob‐
lem because nothing later on needs the original packet.
Such actions can, however, occur in circumstances where the translation
does require the original packet. For example, an OpenFlow output ac‐
tion might direct a packet to a patch port, which might in turn lead to
a ct action that NATs the packet (which cannot be undone), and then af‐
terward when control flow pops back across the patch port some other
action might need to act on the original packet.
Open vSwitch has two different ways to implement this ``save and re‐
store’’ via datapath actions. These capabilities indicate which one
Open vSwitch will choose. When neither is available, Open vSwitch sim‐
ply fails in situations that require this feature.
capabilities : clone: optional string, either true or false
True if the datapath supports OVS_ACTION_ATTR_CLONE action. This
is the preferred option for saving and restoring packets, since
it is intended for the purpose, but old datapaths do not support
it. Open vSwitch will use it whenever it is available.
(The OpenFlow clone action does not always yield a OVS_AC‐
TION_ATTR_CLONE action. It only does so when the datapath sup‐
ports it and the clone brackets actions that otherwise cannot be
undone.)
capabilities : sample_nesting: optional string, containing an integer,
at least 0
Maximum level of nesting allowed by OVS_ACTION_ATTR_SAMPLE ac‐
tion. Open vSwitch misuses this action for saving and restoring
packets when the datapath supports more than 3 levels of nesting
and OVS_ACTION_ATTR_CLONE is not available.
capabilities : ct_eventmask: optional string, either true or false
True if the datapath’s OVS_ACTION_ATTR_CT action implements the
OVS_CT_ATTR_EVENTMASK attribute. When this is true, Open vSwitch
uses the event mask feature to limit the kinds of events re‐
ported to conntrack update listeners. When Open vSwitch doesn’t
limit the event mask, listeners receive reports of numerous usu‐
ally unimportant events, such as TCP state machine changes,
which can waste CPU time.
capabilities : ct_clear: optional string, either true or false
True if the datapath supports OVS_ACTION_ATTR_CT_CLEAR action.
If false, the OpenFlow ct_clear action has no effect on the
datapath.
capabilities : max_hash_alg: optional string, containing an integer, at
least 0
Highest supported dp_hash algorithm. This allows Open vSwitch to
avoid requesting a packet hash that the datapath does not sup‐
port.
capabilities : check_pkt_len: optional string, either true or false
True if the datapath supports OVS_ACTION_ATTR_CHECK_PKT_LEN. If
false, Open vSwitch implements the check_pkt_larger action by
sending every packet through the Open vSwitch slow path, which
is likely to make it too slow for handling traffic in bulk.
capabilities : ct_timeout: optional string, either true or false
True if the datapath supports OVS_CT_ATTR_TIMEOUT in the OVS_AC‐
TION_ATTR_CT action. If false, Open vswitch cannot implement
timeout policies based on connection tracking zones, as config‐
ured through the CT_Timeout_Policy table.
capabilities : explicit_drop_action: optional string, either true or
false
True if the datapath supports OVS_ACTION_ATTR_DROP. If false,
explicit drop action will not be sent to the datapath.
capabilities : ct_zero_snat: optional string, either true or false
True if the datapath supports all-zero SNAT. This is a special
case if the src IP address is configured as all 0’s, i.e.,
nat(src=0.0.0.0). In this case, when a source port collision is
detected during the commit, the source port will be translated
to an ephemeral port. If there is no collision, no SNAT is per‐
formed.
capabilities : ct_flush: optional string, either true or false
True if the datapath supports CT flush OpenFlow Nicira extension
called NXT_CT_FLUSH. The NXT_CT_FLUSH extensions allows to flush
CT entries based on specified parameters.
capabilities : psample: optional string, either true or false
True if the datapath supports OVS_ACTION_ATTR_PSAMPLE. If false,
local sampling will not be supported with the Linux kernel data‐
path.
ct_zone_default_limit: optional integer, in range 0 to 4,294,967,295
Default connection tracking zone limit that is applied to all
zones that didn’t specify the limit explicitly. If the limit is
unspecified the default limit configuration for the datapath is
left intact. The value 0 means unlimited.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
external_ids: map of string-string pairs
CT_Zone TABLE
Connection tracking zone configuration
Summary:
timeout_policy optional CT_Timeout_Policy
limit optional integer, in range 0 to
4,294,967,295
Common Columns:
external_ids map of string-string pairs
Details:
timeout_policy: optional CT_Timeout_Policy
Connection tracking timeout policy for this zone. If a timeout
policy is not specified, it defaults to the timeout policy in
the system.
limit: optional integer, in range 0 to 4,294,967,295
Connection tracking limit for this zone. If the limit is unspec‐
ified the ct_zone_default_limit will be used. The value 0 means
unlimited.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
external_ids: map of string-string pairs
CT_Timeout_Policy TABLE
Connection tracking timeout policy configuration
Summary:
Timeouts:
timeouts map of string-integer pairs, key one of
icmp_first, icmp_reply, tcp_close,
tcp_close_wait, tcp_established,
tcp_fin_wait, tcp_last_ack, tcp_retrans‐
mit, tcp_syn_recv, tcp_syn_sent2,
tcp_syn_sent, tcp_time_wait, tcp_unack,
udp_first, udp_multiple, or udp_single,
value in range 0 to 4,294,967,295
TCP Timeouts:
timeouts : tcp_syn_sent optional integer, in range 0 to
4,294,967,295
timeouts : tcp_syn_recv optional integer, in range 0 to
4,294,967,295
timeouts : tcp_established
optional integer, in range 0 to
4,294,967,295
timeouts : tcp_fin_wait optional integer, in range 0 to
4,294,967,295
timeouts : tcp_close_wait
optional integer, in range 0 to
4,294,967,295
timeouts : tcp_last_ack optional integer, in range 0 to
4,294,967,295
timeouts : tcp_time_wait optional integer, in range 0 to
4,294,967,295
timeouts : tcp_close optional integer, in range 0 to
4,294,967,295
timeouts : tcp_syn_sent2 optional integer, in range 0 to
4,294,967,295
timeouts : tcp_retransmit
optional integer, in range 0 to
4,294,967,295
timeouts : tcp_unack optional integer, in range 0 to
4,294,967,295
UDP Timeouts:
timeouts : udp_first optional integer, in range 0 to
4,294,967,295
timeouts : udp_single optional integer, in range 0 to
4,294,967,295
timeouts : udp_multiple optional integer, in range 0 to
4,294,967,295
ICMP Timeouts:
timeouts : icmp_first optional integer, in range 0 to
4,294,967,295
timeouts : icmp_reply optional integer, in range 0 to
4,294,967,295
Common Columns:
external_ids map of string-string pairs
Details:
Timeouts:
timeouts: map of string-integer pairs, key one of icmp_first, icmp_re‐
ply, tcp_close, tcp_close_wait, tcp_established, tcp_fin_wait,
tcp_last_ack, tcp_retransmit, tcp_syn_recv, tcp_syn_sent2,
tcp_syn_sent, tcp_time_wait, tcp_unack, udp_first, udp_multiple, or
udp_single, value in range 0 to 4,294,967,295
The timeouts column contains key-value pairs used to configure
connection tracking timeouts in a datapath. Key-value pairs that
are not supported by a datapath are ignored. The timeout value
is in seconds.
TCP Timeouts:
timeouts : tcp_syn_sent: optional integer, in range 0 to 4,294,967,295
The timeout for the connection after the first TCP SYN packet
has been seen by conntrack.
timeouts : tcp_syn_recv: optional integer, in range 0 to 4,294,967,295
The timeout of the connection after the first TCP SYN-ACK packet
has been seen by conntrack.
timeouts : tcp_established: optional integer, in range 0 to
4,294,967,295
The timeout of the connection after the connection has been
fully established.
timeouts : tcp_fin_wait: optional integer, in range 0 to 4,294,967,295
The timeout of the connection after the first TCP FIN packet has
been seen by conntrack.
timeouts : tcp_close_wait: optional integer, in range 0 to
4,294,967,295
The timeout of the connection after the first TCP ACK packet has
been seen after it receives TCP FIN packet. This timeout is only
supported by the Linux kernel datapath.
timeouts : tcp_last_ack: optional integer, in range 0 to 4,294,967,295
The timeout of the connection after TCP FIN packets have been
seen by conntrack from both directions. This timeout is only
supported by the Linux kernel datapath.
timeouts : tcp_time_wait: optional integer, in range 0 to 4,294,967,295
The timeout of the connection after conntrack has seen the TCP
ACK packet for the second TCP FIN packet.
timeouts : tcp_close: optional integer, in range 0 to 4,294,967,295
The timeout of the connection after the first TCP RST packet has
been seen by conntrack.
timeouts : tcp_syn_sent2: optional integer, in range 0 to 4,294,967,295
The timeout of the connection when only a TCP SYN packet has
been seen by conntrack from both directions (simultaneous open).
This timeout is only supported by the Linux kernel datapath.
timeouts : tcp_retransmit: optional integer, in range 0 to
4,294,967,295
The timeout of the connection when it exceeds the maximum number
of retransmissions. This timeout is only supported by the Linux
kernel datapath.
timeouts : tcp_unack: optional integer, in range 0 to 4,294,967,295
The timeout of the connection when non-SYN packets create an es‐
tablished connection in TCP loose tracking mode. This timeout is
only supported by the Linux kernel datapath.
UDP Timeouts:
timeouts : udp_first: optional integer, in range 0 to 4,294,967,295
The timeout of the connection after the first UDP packet has
been seen by conntrack. This timeout is only supported by the
userspace datapath.
timeouts : udp_single: optional integer, in range 0 to 4,294,967,295
The timeout of the connection when conntrack only seen UDP
packet from the source host, but the destination host has never
sent one back.
timeouts : udp_multiple: optional integer, in range 0 to 4,294,967,295
The timeout of the connection when UDP packets have been seen in
both directions.
ICMP Timeouts:
timeouts : icmp_first: optional integer, in range 0 to 4,294,967,295
The timeout of the connection after the first ICMP packet has
been seen by conntrack.
timeouts : icmp_reply: optional integer, in range 0 to 4,294,967,295
The timeout of the connection when ICMP packets have been seen
in both direction. This timeout is only supported by the user‐
space datapath.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
external_ids: map of string-string pairs
SSL TABLE
SSL configuration for an Open_vSwitch.
Summary:
private_key string
certificate string
ca_cert string
bootstrap_ca_cert boolean
Common Columns:
external_ids map of string-string pairs
Details:
private_key: string
Name of a PEM file containing the private key used as the
switch’s identity for SSL connections to the controller.
certificate: string
Name of a PEM file containing a certificate, signed by the cer‐
tificate authority (CA) used by the controller and manager, that
certifies the switch’s private key, identifying a trustworthy
switch.
ca_cert: string
Name of a PEM file containing the CA certificate used to verify
that the switch is connected to a trustworthy controller.
bootstrap_ca_cert: boolean
If set to true, then Open vSwitch will attempt to obtain the CA
certificate from the controller on its first SSL connection and
save it to the named PEM file. If it is successful, it will im‐
mediately drop the connection and reconnect, and from then on
all SSL connections must be authenticated by a certificate
signed by the CA certificate thus obtained. This option exposes
the SSL connection to a man-in-the-middle attack obtaining the
initial CA certificate. It may still be useful for bootstrap‐
ping.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
external_ids: map of string-string pairs
sFlow TABLE
A set of sFlow(R) targets. sFlow is a protocol for remote monitoring of
switches.
Summary:
agent optional string
header optional integer
polling optional integer
sampling optional integer
targets set of 1 or more strings
Common Columns:
external_ids map of string-string pairs
Details:
agent: optional string
Determines the agent address, that is, the IP address reported
to collectors as the source of the sFlow data. It may be an IP
address or the name of a network device. In the latter case, the
network device’s IP address is used,
If not specified, the agent device is figured from the first
target address and the routing table. If the routing table does
not contain a route to the target, the IP address defaults to
the local_ip in the collector’s Controller.
If an agent IP address cannot be determined, sFlow is disabled.
header: optional integer
Number of bytes of a sampled packet to send to the collector. If
not specified, the default is 128 bytes.
polling: optional integer
Polling rate in seconds to send port statistics to the collec‐
tor. If not specified, defaults to 30 seconds.
sampling: optional integer
Rate at which packets should be sampled and sent to the collec‐
tor. If not specified, defaults to 400, which means one out of
400 packets, on average, will be sent to the collector.
targets: set of 1 or more strings
sFlow targets in the form ip:port.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
external_ids: map of string-string pairs
IPFIX TABLE
Configuration for sending packets to IPFIX collectors.
IPFIX is a protocol that exports a number of details about flows. The
IPFIX implementation in Open vSwitch samples packets at a configurable
rate, extracts flow information from those packets, optionally caches
and aggregates the flow information, and sends the result to one or
more collectors.
IPFIX in Open vSwitch can be configured two different ways:
• With per-bridge sampling, Open vSwitch performs IPFIX
sampling automatically on all packets that pass through a
bridge. To configure per-bridge sampling, create an IPFIX
record and point a Bridge table’s ipfix column to it. The
Flow_Sample_Collector_Set table is not used for per-
bridge sampling.
• With flow-based sampling, sample actions in the OpenFlow
flow table drive IPFIX sampling. See ovs-actions(7) for a
description of the sample action.
Flow-based sampling also requires database configuration:
create a IPFIX record that describes the IPFIX configura‐
tion and a Flow_Sample_Collector_Set record that points
to the Bridge whose flow table holds the sample actions
and to IPFIX record. The ipfix in the Bridge table is not
used for flow-based sampling.
Summary:
targets set of strings
cache_active_timeout optional integer, in range 0 to 4,200
cache_max_flows optional integer, in range 0 to
4,294,967,295
stats_interval optional integer, in range 1 to 3,600
template_interval optional integer, in range 1 to 3,600
other_config : enable-tunnel-sampling
optional string, either true or false
other_config : virtual_obs_id optional string
Per-Bridge Sampling:
sampling optional integer, in range 1 to
4,294,967,295
obs_domain_id optional integer, in range 0 to
4,294,967,295
obs_point_id optional integer, in range 0 to
4,294,967,295
other_config : enable-input-sampling
optional string, either true or false
other_config : enable-output-sampling
optional string, either true or false
Common Columns:
external_ids map of string-string pairs
Details:
targets: set of strings
IPFIX target collectors in the form ip:port.
cache_active_timeout: optional integer, in range 0 to 4,200
The maximum period in seconds for which an IPFIX flow record is
cached and aggregated before being sent. If not specified, de‐
faults to 0. If 0, caching is disabled.
cache_max_flows: optional integer, in range 0 to 4,294,967,295
The maximum number of IPFIX flow records that can be cached at a
time. If not specified, defaults to 0. If 0, caching is dis‐
abled.
stats_interval: optional integer, in range 1 to 3,600
Interval (in seconds) for sending IPFIX exporting process sta‐
tistics according to IETF RFC 5101 Section 4.3.
Default value is 600
template_interval: optional integer, in range 1 to 3,600
Interval (in seconds) for sending IPFIX Template information for
each Observation Domain ID.
Default value is 600
other_config : enable-tunnel-sampling: optional string, either true or
false
Set to true to enable sampling and reporting tunnel header 7-tu‐
ples in IPFIX flow records. Tunnel sampling is enabled by de‐
fault.
The following enterprise entities report the sampled tunnel
info:
tunnelType:
ID: 891, and enterprise ID 6876 (VMware).
type: unsigned 8-bit integer.
data type semantics: identifier.
description: Identifier of the layer 2 network overlay
network encapsulation type: 0x01 VxLAN, 0x02 GRE, 0x03
LISP, 0x07 GENEVE.
tunnelKey:
ID: 892, and enterprise ID 6876 (VMware).
type: variable-length octetarray.
data type semantics: identifier.
description: Key which is used for identifying an indi‐
vidual traffic flow within a VxLAN (24-bit VNI), GENEVE
(24-bit VNI), GRE (32-bit key), or LISP (24-bit instance
ID) tunnel. The key is encoded in this octetarray as a
3-, 4-, or 8-byte integer ID in network byte order.
tunnelSourceIPv4Address:
ID: 893, and enterprise ID 6876 (VMware).
type: unsigned 32-bit integer.
data type semantics: identifier.
description: The IPv4 source address in the tunnel IP
packet header.
tunnelDestinationIPv4Address:
ID: 894, and enterprise ID 6876 (VMware).
type: unsigned 32-bit integer.
data type semantics: identifier.
description: The IPv4 destination address in the tunnel
IP packet header.
tunnelProtocolIdentifier:
ID: 895, and enterprise ID 6876 (VMware).
type: unsigned 8-bit integer.
data type semantics: identifier.
description: The value of the protocol number in the tun‐
nel IP packet header. The protocol number identifies the
tunnel IP packet payload type.
tunnelSourceTransportPort:
ID: 896, and enterprise ID 6876 (VMware).
type: unsigned 16-bit integer.
data type semantics: identifier.
description: The source port identifier in the tunnel
transport header. For the transport protocols UDP, TCP,
and SCTP, this is the source port number given in the re‐
spective header.
tunnelDestinationTransportPort:
ID: 897, and enterprise ID 6876 (VMware).
type: unsigned 16-bit integer.
data type semantics: identifier.
description: The destination port identifier in the tun‐
nel transport header. For the transport protocols UDP,
TCP, and SCTP, this is the destination port number given
in the respective header.
Before Open vSwitch 2.5.90, other_config:enable-tunnel-sampling
was only supported with per-bridge sampling, and ignored other‐
wise. Open vSwitch 2.5.90 and later support other_config:enable-
tunnel-sampling for per-bridge and per-flow sampling.
other_config : virtual_obs_id: optional string
A string that accompanies each IPFIX flow record. Its intended
use is for the ``virtual observation ID,’’ an identifier of a
virtual observation point that is locally unique in a virtual
network. It describes a location in the virtual network where IP
packets can be observed. The maximum length is 254 bytes. If not
specified, the field is omitted from the IPFIX flow record.
The following enterprise entity reports the specified virtual
observation ID:
virtualObsID:
ID: 898, and enterprise ID 6876 (VMware).
type: variable-length string.
data type semantics: identifier.
description: A virtual observation domain ID that is lo‐
cally unique in a virtual network.
This feature was introduced in Open vSwitch 2.5.90.
Per-Bridge Sampling:
These values affect only per-bridge sampling. See above for a descrip‐
tion of the differences between per-bridge and flow-based sampling.
sampling: optional integer, in range 1 to 4,294,967,295
The rate at which packets should be sampled and sent to each
target collector. If not specified, defaults to 400, which means
one out of 400 packets, on average, will be sent to each target
collector.
obs_domain_id: optional integer, in range 0 to 4,294,967,295
The IPFIX Observation Domain ID sent in each IPFIX packet. If
not specified, defaults to 0.
obs_point_id: optional integer, in range 0 to 4,294,967,295
The IPFIX Observation Point ID sent in each IPFIX flow record.
If not specified, defaults to 0.
other_config : enable-input-sampling: optional string, either true or
false
By default, Open vSwitch samples and reports flows at bridge
port input in IPFIX flow records. Set this column to false to
disable input sampling.
other_config : enable-output-sampling: optional string, either true or
false
By default, Open vSwitch samples and reports flows at bridge
port output in IPFIX flow records. Set this column to false to
disable output sampling.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
external_ids: map of string-string pairs
Flow_Sample_Collector_Set TABLE
A set of IPFIX or local sampling collectors of packet samples generated
by OpenFlow sample actions.
If the column ipfix contains a reference to a valid IPFIX entry, sam‐
ples will be emitted via IPFIX. This mechanism is known as flow-based
IPFIX sampling, as opposed to bridge-based sampling (see the IPFIX ta‐
ble for a description of the two forms).
If the column local_group_id contains an integer and the running data‐
path supports local sample emission, packets will be sent to some local
sample collector. Samples will contain the group number specified by
local_group_id which helps identify their source as well as a 64-bit
cookie result from the concatenation of the observation_domain_id an
the observation_point_id in network byte order. The way the sample is
emitted and made available for local collectors is datapath-specific.
Currently only Linux kernel datapath supports local sampling which is
implemented by sending the packet to the psample netlink multicast
group.
Note: both local_group_id and ipfix can be configured simultaneously.
Summary:
id integer, in range 0 to 4,294,967,295
bridge Bridge
ipfix optional IPFIX
local_group_id optional integer, in range 0 to
4,294,967,295
Common Columns:
external_ids map of string-string pairs
Details:
id: integer, in range 0 to 4,294,967,295
The ID of this collector set, unique among the bridge’s collec‐
tor sets, to be used as the collector_set_id in OpenFlow sample
actions.
bridge: Bridge
The bridge into which OpenFlow sample actions can be added to
send packet samples to this set of IPFIX collectors.
ipfix: optional IPFIX
Configuration of the set of IPFIX collectors to send one flow
record per sampled packet to.
local_group_id: optional integer, in range 0 to 4,294,967,295
Configuration of the sample group id to be used in local sam‐
pling.
Common Columns:
The overall purpose of these columns is described under Common Columns
at the beginning of this document.
external_ids: map of string-string pairs
AutoAttach TABLE
Auto Attach configuration within a bridge. The IETF Auto-Attach SPBM
draft standard describes a compact method of using IEEE 802.1AB Link
Layer Discovery Protocol (LLDP) together with a IEEE 802.1aq Shortest
Path Bridging (SPB) network to automatically attach network devices to
individual services in a SPB network. The intent here is to allow net‐
work applications and devices using OVS to be able to easily take ad‐
vantage of features offered by industry standard SPB networks.
Auto Attach (AA) uses LLDP to communicate between a directly connected
Auto Attach Client (AAC) and Auto Attach Server (AAS). The LLDP proto‐
col is extended to add two new Type-Length-Value tuples (TLVs). The
first new TLV supports the ongoing discovery of directly connected AA
correspondents. Auto Attach operates by regularly transmitting AA dis‐
covery TLVs between the AA client and AA server. By exchanging these
discovery messages, both the AAC and AAS learn the system name and sys‐
tem description of their peer. In the OVS context, OVS operates as the
AA client and the AA server resides on a switch at the edge of the SPB
network.
Once AA discovery has been completed the AAC then uses the second new
TLV to deliver identifier mappings from the AAC to the AAS. A primary
feature of Auto Attach is to facilitate the mapping of VLANs defined
outside the SPB network onto service ids (ISIDs) defined within the SPM
network. By doing so individual external VLANs can be mapped onto spe‐
cific SPB network services. These VLAN id to ISID mappings can be con‐
figured and managed locally using new options added to the ovs-vsctl
command.
The Auto Attach OVS feature does not provide a full implementation of
the LLDP protocol. Support for the mandatory TLVs as defined by the
LLDP standard and support for the AA TLV extensions is provided. LLDP
protocol support in OVS can be enabled or disabled on a port by port
basis. LLDP support is disabled by default.
Summary:
system_name string
system_description string
mappings map of integer-integer pairs, key in
range 0 to 16,777,215, value in range 0
to 4,095
Details:
system_name: string
The system_name string is exported in LLDP messages. It should
uniquely identify the bridge in the network.
system_description: string
The system_description string is exported in LLDP messages. It
should describe the type of software and hardware.
mappings: map of integer-integer pairs, key in range 0 to 16,777,215,
value in range 0 to 4,095
A mapping from SPB network Individual Service Identifier (ISID)
to VLAN id.
Open vSwitch 3.4.0 DB Schema 8.7.0 ovs-vswitchd.conf.db(5)