ovn-controller(8)                 OVN Manual                 ovn-controller(8)

NAME
       ovn-controller - Open Virtual Network local controller

SYNOPSIS
       ovn-controller [options] [ovs-database]

DESCRIPTION
       ovn-controller is the local controller daemon for OVN, the Open Virtual
       Network.  It connects up to the OVN Southbound database (see ovn-sb(5))
       over the OVSDB protocol, and down to the  Open  vSwitch  database  (see
       ovs-vswitchd.conf.db(5)) over the OVSDB protocol and to ovs-vswitchd(8)
       via OpenFlow. Each hypervisor and software gateway in an OVN deployment
       runs its own independent copy of ovn-controller; thus, ovn-controller’s
       downward  connections  are machine-local and do not run over a physical
       network.

ACL LOGGING
       ACL log messages are logged through ovn-controller’s logging mechanism.
       ACL log entries have the module acl_log at log level info.  Configuring
       logging is described below in the Logging Options section.

OPTIONS
   Daemon Options
       --pidfile[=pidfile]
              Causes a file (by default, program.pid) to be created indicating
              the  PID  of the running process. If the pidfile argument is not
              specified, or if it does not begin with /, then it is created in
              .

              If --pidfile is not specified, no pidfile is created.

       --overwrite-pidfile
              By default, when --pidfile is specified and the  specified  pid‐
              file already exists and is locked by a running process, the dae‐
              mon refuses to start. Specify --overwrite-pidfile to cause it to
              instead overwrite the pidfile.

              When --pidfile is not specified, this option has no effect.

       --detach
              Runs  this  program  as a background process. The process forks,
              and in the child it starts a new session,  closes  the  standard
              file descriptors (which has the side effect of disabling logging
              to  the  console), and changes its current directory to the root
              (unless --no-chdir is specified). After the child completes  its
              initialization, the parent exits.

       --monitor
              Creates  an  additional  process  to monitor this program. If it
              dies due to a signal that indicates a programming  error  (SIGA‐‐
              BRT, SIGALRM, SIGBUS, SIGFPE, SIGILL, SIGPIPE, SIGSEGV, SIGXCPU,
              or SIGXFSZ) then the monitor process starts a new copy of it. If
              the daemon dies or exits for another reason, the monitor process
              exits.

              This  option  is  normally used with --detach, but it also func‐
              tions without it.

       --no-chdir
              By default, when --detach is specified, the daemon  changes  its
              current  working  directory  to  the root directory after it de‐
              taches. Otherwise, invoking the daemon from a carelessly  chosen
              directory  would  prevent  the administrator from unmounting the
              file system that holds that directory.

              Specifying --no-chdir suppresses this behavior,  preventing  the
              daemon  from changing its current working directory. This may be
              useful for collecting core files, since it is common behavior to
              write core dumps into the current working directory and the root
              directory is not a good directory to use.

              This option has no effect when --detach is not specified.

       --no-self-confinement
              By default this daemon will try to self-confine itself  to  work
              with  files  under  well-known  directories  determined at build
              time. It is better to stick with this default behavior  and  not
              to  use  this  flag  unless some other Access Control is used to
              confine daemon. Note that in contrast to  other  access  control
              implementations  that  are  typically enforced from kernel-space
              (e.g. DAC or MAC), self-confinement is imposed  from  the  user-
              space daemon itself and hence should not be considered as a full
              confinement  strategy,  but instead should be viewed as an addi‐
              tional layer of security.

       --user=user:group
              Causes this program to run as  a  different  user  specified  in
              user:group,  thus  dropping  most  of the root privileges. Short
              forms user and :group are also allowed,  with  current  user  or
              group  assumed,  respectively.  Only daemons started by the root
              user accepts this argument.

              On   Linux,   daemons   will   be   granted   CAP_IPC_LOCK   and
              CAP_NET_BIND_SERVICES  before  dropping root privileges. Daemons
              that interact with a datapath, such  as  ovs-vswitchd,  will  be
              granted  three  additional  capabilities,  namely CAP_NET_ADMIN,
              CAP_NET_BROADCAST and CAP_NET_RAW. The  capability  change  will
              apply even if the new user is root.

              On Windows, this option is not currently supported. For security
              reasons,  specifying  this  option will cause the daemon process
              not to start.

   Logging Options
       -v[spec]
       --verbose=[spec]
            Sets logging levels. Without any spec,  sets  the  log  level  for
            every  module and destination to dbg. Otherwise, spec is a list of
            words separated by spaces or commas or colons, up to one from each
            category below:

            •      A valid module name, as displayed by the vlog/list  command
                   on ovs-appctl(8), limits the log level change to the speci‐
                   fied module.

            •      syslog,  console, or file, to limit the log level change to
                   only to the system log, to the console, or to a  file,  re‐
                   spectively.  (If  --detach  is specified, the daemon closes
                   its standard file descriptors, so logging  to  the  console
                   will have no effect.)

                   On  Windows  platform,  syslog is accepted as a word and is
                   only useful along with the --syslog-target option (the word
                   has no effect otherwise).

            •      off, emer, err, warn, info, or  dbg,  to  control  the  log
                   level.  Messages  of  the  given severity or higher will be
                   logged, and messages of lower  severity  will  be  filtered
                   out.  off filters out all messages. See ovs-appctl(8) for a
                   definition of each log level.

            Case is not significant within spec.

            Regardless of the log levels set for file, logging to a file  will
            not take place unless --log-file is also specified (see below).

            For compatibility with older versions of OVS, any is accepted as a
            word but has no effect.

       -v
       --verbose
            Sets  the  maximum  logging  verbosity level, equivalent to --ver‐‐
            bose=dbg.

       -vPATTERN:destination:pattern
       --verbose=PATTERN:destination:pattern
            Sets the log pattern for destination to pattern. Refer to  ovs-ap‐‐
            pctl(8) for a description of the valid syntax for pattern.

       -vFACILITY:facility
       --verbose=FACILITY:facility
            Sets  the RFC5424 facility of the log message. facility can be one
            of kern, user, mail, daemon, auth, syslog, lpr, news, uucp, clock,
            ftp, ntp, audit, alert, clock2, local0,  local1,  local2,  local3,
            local4, local5, local6 or local7. If this option is not specified,
            daemon  is used as the default for the local system syslog and lo‐‐
            cal0 is used while sending a message to the  target  provided  via
            the --syslog-target option.

       --log-file[=file]
            Enables  logging  to a file. If file is specified, then it is used
            as the exact name for the log file. The default log file name used
            if file is omitted is /usr/local/var/log/ovn/program.log.

       --syslog-target=host:port
            Send syslog messages to UDP port on host, in addition to the  sys‐
            tem  syslog.  The host must be a numerical IP address, not a host‐
            name.

       --syslog-method=method
            Specify method as how syslog messages should  be  sent  to  syslog
            daemon. The following forms are supported:

            •      libc,  to use the libc syslog() function. Downside of using
                   this options is that libc adds fixed prefix to  every  mes‐
                   sage  before  it is actually sent to the syslog daemon over
                   /dev/log UNIX domain socket.

            •      unix:file, to use a UNIX domain socket directly. It is pos‐
                   sible to specify arbitrary message format with this option.
                   However, rsyslogd 8.9 and older  versions  use  hard  coded
                   parser  function anyway that limits UNIX domain socket use.
                   If you want to use  arbitrary  message  format  with  older
                   rsyslogd  versions, then use UDP socket to localhost IP ad‐
                   dress instead.

            •      udp:ip:port, to use a UDP socket. With this  method  it  is
                   possible  to  use  arbitrary message format also with older
                   rsyslogd. When sending syslog messages over UDP socket  ex‐
                   tra precaution needs to be taken into account, for example,
                   syslog daemon needs to be configured to listen on the spec‐
                   ified  UDP  port, accidental iptables rules could be inter‐
                   fering with local syslog traffic and there are  some  secu‐
                   rity  considerations  that apply to UDP sockets, but do not
                   apply to UNIX domain sockets.

            •      null, to discard all messages logged to syslog.

            The default is taken from the OVS_SYSLOG_METHOD environment  vari‐
            able; if it is unset, the default is libc.

   PKI Options
       PKI  configuration  is required in order to use SSL for the connections
       to the Northbound and Southbound databases.

              -p privkey.pem
              --private-key=privkey.pem
                   Specifies a PEM file containing the  private  key  used  as
                   identity for outgoing SSL connections.

              -c cert.pem
              --certificate=cert.pem
                   Specifies  a  PEM file containing a certificate that certi‐
                   fies the private key specified on -p or --private-key to be
                   trustworthy. The certificate must be signed by the certifi‐
                   cate authority (CA) that the peer in SSL  connections  will
                   use to verify it.

              -C cacert.pem
              --ca-cert=cacert.pem
                   Specifies a PEM file containing the CA certificate for ver‐
                   ifying certificates presented to this program by SSL peers.
                   (This  may  be  the  same certificate that SSL peers use to
                   verify the certificate specified on -c or --certificate, or
                   it may be a different one, depending on the PKI  design  in
                   use.)

              -C none
              --ca-cert=none
                   Disables  verification  of  certificates  presented  by SSL
                   peers. This introduces a security risk,  because  it  means
                   that  certificates  cannot be verified to be those of known
                   trusted hosts.

              --bootstrap-ca-cert=cacert.pem
                     When cacert.pem exists, this option has the  same  effect
                     as  -C  or --ca-cert. If it does not exist, then the exe‐
                     cutable will attempt to obtain the  CA  certificate  from
                     the  SSL  peer on its first SSL connection and save it to
                     the named PEM file. If it is successful, it will  immedi‐
                     ately drop the connection and reconnect, and from then on
                     all  SSL  connections must be authenticated by a certifi‐
                     cate 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, but
                     it may be useful for bootstrapping.

                     This option is only useful if the SSL peer sends  its  CA
                     certificate as part of the SSL certificate chain. The SSL
                     protocol  does not require the server to send the CA cer‐
                     tificate.

                     This option is mutually exclusive with -C and --ca-cert.

              --peer-ca-cert=peer-cacert.pem
                     Specifies a PEM file that contains one or more additional
                     certificates to send to SSL peers. peer-cacert.pem should
                     be the CA certificate used to sign the program’s own cer‐
                     tificate, that is, the certificate  specified  on  -c  or
                     --certificate.  If  the  program’s  certificate  is self-
                     signed,  then  --certificate  and  --peer-ca-cert  should
                     specify the same file.

                     This  option  is  not useful in normal operation, because
                     the SSL peer must already have the CA certificate for the
                     peer to have any confidence in  the  program’s  identity.
                     However,  this  offers  a  way  for a new installation to
                     bootstrap the CA certificate on its first SSL connection.

   Other Options
       -h
       --help
            Prints a brief help message to the console.

       -V
       --version
            Prints version information to the console.

CONFIGURATION
       ovn-controller retrieves most of its configuration information from the
       local Open vSwitch’s ovsdb-server instance.  The  default  location  is
       db.sock in the local Open vSwitch’s "run" directory. It may be overrid‐
       den  by specifying the ovs-database argument as an OVSDB active or pas‐
       sive connection method, as described in ovsdb(7).

       ovn-controller assumes it gets configuration information from the  fol‐
       lowing keys in the Open_vSwitch table of the local OVS instance:

              external_ids:system-id
                     The  chassis  name  to use in the Chassis table. Changing
                     the system-id while ovn-controller is running is not  di‐
                     rectly  supported.  Users  have two options: either first
                     gracefully stop ovn-controller  or  manually  delete  the
                     stale  Chassis and Chassis_Private records after changing
                     the system-id.

              external_ids:hostname
                     The hostname to use in the Chassis table.

              external_ids:ovn-bridge
                     The integration bridge to which  logical  ports  are  at‐
                     tached.  The  default  is br-int. If this bridge does not
                     exist when ovn-controller starts, it will be created  au‐
                     tomatically  with  the default configuration suggested in
                     ovn-architecture(7).

              external_ids:ovn-bridge-datapath-type
                     This configuration is optional. If set, then the datapath
                     type of the integration bridge will be set to the config‐
                     ured value. If this option  is  not  set,  then  ovn-con‐‐
                     troller will not modify the existing datapath-type of the
                     integration bridge.

              external_ids:ovn-remote
                     The  OVN  database that this system should connect to for
                     its configuration, in one of the  same  forms  documented
                     above for the ovs-database.

              external_ids:ovn-monitor-all
                     A boolean value that tells if ovn-controller should moni‐
                     tor  all  records  of  tables  in ovs-database. If set to
                     false, it will conditionally monitor the records that  is
                     needed in the current chassis.

                     It is more efficient to set it to true in use cases where
                     the  chassis  would  anyway  need  to monitor most of the
                     records in OVN Southbound database, which would save  the
                     overhead  of conditions processing, especially for server
                     side. Typically, set it to true for environments that all
                     workloads need to be reachable from each other.

                     Default value is false.

              external_ids:ovn-remote-probe-interval
                     The inactivity probe interval of the  connection  to  the
                     OVN  database,  in milliseconds. If the value is zero, it
                     disables the connection keepalive feature.

                     If the value is nonzero, then it  will  be  forced  to  a
                     value of at least 1000 ms.

              external_ids:ovn-openflow-probe-interval
                     The  inactivity probe interval of the OpenFlow connection
                     to the OpenvSwitch integration bridge, in seconds. If the
                     value is zero, it disables the connection keepalive  fea‐
                     ture.

                     If  the  value  is  nonzero,  then it will be forced to a
                     value of at least 5s.

              external_ids:ovn-encap-type
                     The encapsulation type that a chassis should use to  con‐
                     nect  to  this  node. Multiple encapsulation types may be
                     specified with a comma-separated list. Each listed encap‐
                     sulation type will be paired with ovn-encap-ip.

                     Supported tunnel types  for  connecting  hypervisors  and
                     gateways are geneve, vxlan, and stt.

                     Due to the limited amount of metadata in vxlan, the capa‐
                     bilities and performance of connected gateways and hyper‐
                     visors will be reduced versus other tunnel formats.

              external_ids:ovn-encap-ip
                     The  IP  address  that a chassis should use to connect to
                     this node using encapsulation types specified  by  exter‐‐
                     nal_ids:ovn-encap-type.

              external_ids:ovn-bridge-mappings
                     A  list  of  key-value  pairs that map a physical network
                     name to a local ovs bridge that provides connectivity  to
                     that  network. An example value mapping two physical net‐
                     work  names  to  two  ovs   bridges   would   be:   phys‐‐
                     net1:br-eth0,physnet2:br-eth1.

              external_ids:ovn-encap-csum
                     ovn-encap-csum indicates that encapsulation checksums can
                     be  transmitted and received with reasonable performance.
                     It is a hint to senders transmitting data to this chassis
                     that they should use checksums to protect  OVN  metadata.
                     Set  to  true to enable or false to disable. Depending on
                     the capabilities of the network interface card,  enabling
                     encapsulation  checksum  may  incur  performance loss. In
                     such cases, encapsulation checksums can be disabled.

              external_ids:ovn-encap-tos
                     ovn-encap-tos indicates the value to be  applied  to  OVN
                     tunnel   interface’s   option:tos  as  specified  in  the
                     Open_vSwitch database Interface table.  Please  refer  to
                     Open VSwitch Manual for details.

              external_ids:ovn-cms-options
                     A list of options that will be consumed by the CMS Plugin
                     and which specific to this particular chassis. An example
                     would be: cms_option1,cms_option2:foo.

              external_ids:ovn-transport-zones
                     The  transport  zone(s)  that  this  chassis  belongs to.
                     Transport zones is a way to group  different  chassis  so
                     that  tunnels are only formed between members of the same
                     group(s). Multiple transport zones may be specified  with
                     a comma-separated list. For example: tz1,tz2,tz3.

                     If  not set, the Chassis will be considered part of a de‐
                     fault transport zone.

              external_ids:ovn-chassis-mac-mappings
                     A list of key-value pairs that map a chassis specific mac
                     to a physical network name. An example value mapping  two
                     chassis  macs  to  two  physical  network names would be:
                     physnet1:aa:bb:cc:dd:ee:ff,physnet2:a1:b2:c3:d4:e5:f6.
                     These are the macs that  ovn-controller  will  replace  a
                     router  port mac with, if packet is going from a distrib‐
                     uted router port on vlan type logical switch.

              external_ids:ovn-is-interconn
                     The boolean flag indicates if the chassis is used  as  an
                     interconnection gateway.

              external_ids:ovn-match-northd-version
                     The  boolean  flag  indicates  if ovn-controller needs to
                     check ovn-northd version. If this flag is set to true and
                     the ovn-northd’’s  version  (reported  in  the  Southbound
                     database)  doesn’t match with the ovn-controller’’s inter‐
                     nal version, then it will stop processing the  southbound
                     and  local  Open  vSwitch  database  changes. The default
                     value is considered false if this option is not defined.

              external_ids:ovn-ofctrl-wait-before-clear
                     The time, in milliseconds, to wait before clearing  flows
                     in  OVS  after  OpenFlow  connection/reconnection  during
                     ovn-controller initialization. The purpose of  this  wait
                     is  to  give  time  for ovn-controller to compute the new
                     flows before clearing existing ones, to avoid data  plane
                     down  time during ovn-controller restart/upgrade at large
                     scale environments where recomputing the flows takes more
                     than a few seconds or even longer. It  is  difficult  for
                     ovn-controller  to determine when the new flows computing
                     is completed, because of the dynamics in the cloud  envi‐
                     ronments, which is why this configuration is provided for
                     users to adjust based on the scale of the environment. By
                     default,  it  is  0,  which means clearing existing flows
                     without waiting. Not setting the value, or setting it too
                     small, may result in data  plane  down  time  during  up‐
                     grade/restart, while setting it too big may result in un‐
                     necessary  extra  control  plane  latency of applying new
                     changes of CMS during upgrade/restart. In most  cases,  a
                     slightly  bigger  value is not harmful, because the extra
                     control plane latency happens only once during the  Open‐
                     Flow  connection.  To get a reasonable range of the value
                     setting, it is recommended to run the below commands on a
                     node in the target environment and then set this configu‐
                     ration to twice the value of Maximum shown in the  output
                     of the second command.

                     •      ovn-appctl -t ovn-controller inc-engine/recomputeovn-appctl    -t   ovn-controller   stopwatch/show
                            flow-generation

              external_ids:ovn-enable-lflow-cache
                     The boolean flag indicates if ovn-controller  should  en‐
                     able/disable  the  logical  flow  in-memory cache it uses
                     when processing Southbound database logical flow changes.
                     By default caching is enabled.

              external_ids:ovn-limit-lflow-cache
                     When used, this configuration value determines the  maxi‐
                     mum  number  of logical flow cache entries ovn-controller
                     may create when the logical flow cache is enabled. By de‐
                     fault the size of the cache is unlimited.

              external_ids:ovn-memlimit-lflow-cache-kb
                     When used, this configuration value determines the  maxi‐
                     mum size of the logical flow cache (in KB) ovn-controller
                     may create when the logical flow cache is enabled. By de‐
                     fault the size of the cache is unlimited.

              external_ids:ovn-trim-limit-lflow-cache
                     When used, this configuration value sets the minimum num‐
                     ber  of  entries  in the logical flow cache starting with
                     which automatic memory trimming is performed. By  default
                     this is set to 10000 entries.

              external_ids:ovn-trim-wmark-perc-lflow-cache
                     When  used,  this configuration value sets the percentage
                     from the high watermark number of entries in the  logical
                     flow  cache under which automatic memory trimming is per‐
                     formed. E.g., if the trim watermark percentage is set  to
                     50%, automatic memory trimming happens only when the num‐
                     ber  of entries in the logical flow cache gets reduced to
                     less than half of the last measured  high  watermark.  By
                     default this is set to 50.

              external_ids:ovn-trim-timeout-ms
                     When  used,  this configuration value specifies the time,
                     in milliseconds, since the last logical flow cache opera‐
                     tion after which ovn-controller performs memory  trimming
                     regardless of how many entries there are in the cache. By
                     default this is set to 30000 (30 seconds).

              external_ids:ovn-set-local-ip
                     The  boolean flag indicates if ovn-controller when create
                     tunnel ports should set local_ip parameter. Can be  hepl‐
                     ful  to  pin source outer IP for the tunnel when multiple
                     interfaces are used on the host for overlay traffic.

              external_ids:garp-max-timeout-sec
                     When used, this configuration value specifies the maximum
                     timeout (in seconds) between two consecutive GARP packets
                     sent by ovn-controller. ovn-controller by  default  sends
                     just  4 GARP packets with an exponential backoff timeout.
                     Setting external_ids:garp-max-timeout-sec allows  to  cap
                     for  the  exponential  backoff  used by ovn-controller to
                     send GARPs packets.

       ovn-controller reads the following values from the  Open_vSwitch  data‐
       base of the local OVS instance:

              datapath-type from Bridge table
                     This  value is read from local OVS integration bridge row
                     of Bridge table and populated  in  other_config:datapath-
                     type of the Chassis table in the OVN_Southbound database.

              iface-types from Open_vSwitch table
                     This  value  is  populated in external_ids:iface-types of
                     the Chassis table in the OVN_Southbound database.

              private_key, certificate, ca_cert, and bootstrap_ca_cert from
              SSL table
                     These values provide the SSL configuration used for  con‐
                     necting to the OVN southbound database server when an SSL
                     connection  type  is  configured via external_ids:ovn-re‐‐
                     mote. Note that this SSL configuration can also  be  pro‐
                     vided  via command-line options, the configuration in the
                     database takes precedence if both are present.

OPEN VSWITCH DATABASE USAGE
       ovn-controller uses a number of external_ids keys in the  Open  vSwitch
       database  to  keep track of ports and interfaces. For proper operation,
       users should not change or clear these keys:

              external_ids:ovn-chassis-id in the Port table
                     The presence of this key identifies a tunnel port  within
                     the  integration  bridge as one created by ovn-controller
                     to reach a remote chassis. Its value is the chassis ID of
                     the remote chassis.

              external_ids:ct-zone-* in the Bridge table
                     Logical ports and gateway routers are assigned a  connec‐
                     tion  tracking  zone  by ovn-controller for stateful ser‐
                     vices. To keep state across restarts  of  ovn-controller,
                     these  keys are stored in the integration bridge’s Bridge
                     table. The name contains a prefix of ct-zone- followed by
                     the name of the logical port  or  gateway  router’s  zone
                     key.  The value for this key identifies the zone used for
                     this port.

              external_ids:ovn-localnet-port in the Port table
                     The presence of this key identifies a patch port  as  one
                     created  by  ovn-controller  to  connect  the integration
                     bridge and another bridge to implement a localnet logical
                     port. Its value is the name of the logical port with type
                     set to localnet that  the  port  implements.  See  exter‐‐
                     nal_ids:ovn-bridge-mappings, above, for more information.

                     Each  localnet  logical  port is implemented as a pair of
                     patch ports, one in the integration bridge, one in a dif‐
                     ferent  bridge,  with  the  same  external_ids:ovn-local‐‐
                     net-port value.

              external_ids:ovn-l2gateway-port in the Port table
                     The  presence  of this key identifies a patch port as one
                     created by  ovn-controller  to  connect  the  integration
                     bridge  and another bridge to implement a l2gateway logi‐
                     cal port. Its value is the name of the logical port  with
                     type  set  to l2gateway that the port implements. See ex‐‐
                     ternal_ids:ovn-bridge-mappings, above, for more  informa‐
                     tion.

                     Each  l2gateway  logical port is implemented as a pair of
                     patch ports, one in the integration bridge, one in a dif‐
                     ferent bridge,  with  the  same  external_ids:ovn-l2gate‐‐
                     way-port value.

              external-ids:ovn-l3gateway-port in the Port table
                     This  key  identifies  a  patch  port  as  one created by
                     ovn-controller to implement a l3gateway logical port. Its
                     value is the name of the logical port with  type  set  to
                     l3gateway.  This patch port is similar to the OVN logical
                     patch port, except that l3gateway port can only be  bound
                     to a paticular chassis.

              external-ids:ovn-logical-patch-port in the Port table
                     This  key  identifies  a  patch  port  as  one created by
                     ovn-controller to implement an  OVN  logical  patch  port
                     within  the  integration bridge. Its value is the name of
                     the OVN logical patch port that it implements.

              external-ids:ovn-startup-ts in the Bridge table
                     This key represents the timestamp  (in  milliseconds)  at
                     which ovn-controller process was started.

              external-ids:ovn-nb-cfg in the Bridge table
                     This   key   represents   the   last   known   OVN_South‐‐
                     bound.SB_Global.nb_cfg value for  which  all  flows  have
                     been successfully installed in OVS.

              external-ids:ovn-nb-cfg-ts in the Bridge table
                     This  key  represents  the timestamp (in milliseconds) of
                     the last known OVN_Southbound.SB_Global.nb_cfg value  for
                     which all flows have been successfully installed in OVS.

              external_ids:ovn-installed and external_ids:ovn-installed-ts in
              the Interface table
                     This key is set after all openflow operations correspond‐
                     ing  to  the  OVS  interface  have been processed by ovs-
                     vswitchd. At the same time a timestamp,  in  milliseconds
                     since   the  epoch,  is  stored  in  external_ids:ovn-in‐‐
                     stalled-ts.

OVN SOUTHBOUND DATABASE USAGE
       ovn-controller reads from much of the OVN_Southbound database to  guide
       its operation. ovn-controller also writes to the following tables:

              Chassis
                     Upon  startup, ovn-controller creates a row in this table
                     to represent its own chassis. Upon graceful  termination,
                     e.g.  with  ovs-appctl  -t  ovn-controller  exit (but not
                     SIGTERM), ovn-controller removes its row.

              Encap  Upon startup, ovn-controller creates a  row  or  rows  in
                     this  table  that  represent the tunnel encapsulations by
                     which its chassis can be reached, and points its  Chassis
                     row  to  them.  Upon graceful termination, ovn-controller
                     removes these rows.

              Port_Binding
                     At runtime, ovn-controller sets the  chassis  columns  of
                     ports  that  are  resident on its chassis to point to its
                     Chassis row, and, conversely, clears the  chassis  column
                     of  ports that point to its Chassis row but are no longer
                     resident on its chassis. The chassis column  has  a  weak
                     reference  type,  so when ovn-controller gracefully exits
                     and removes its Chassis row, the database server automat‐
                     ically clears any remaining references to that row.

              MAC_Binding
                     At runtime, ovn-controller updates the MAC_Binding  table
                     as  instructed  by  put_arp  and  put_nd logical actions.
                     These changes persist beyond  the  lifetime  of  ovn-con‐‐
                     troller.

RUNTIME MANAGEMENT COMMANDS
       ovs-appctl  can  send commands to a running ovn-controller process. The
       currently supported commands are described below.

              exit   Causes ovn-controller to gracefully terminate.

              ct-zone-list
                     Lists each local logical port and its connection tracking
                     zone.

              meter-table-list
                     Lists each meter table entry and its local meter id.

              group-table-list
                     Lists each group table entry and its local group id.

              inject-pkt microflow
                     Injects microflow into the  connected  Open  vSwitch  in‐
                     stance.  microflow  must  contain an ingress logical port
                     (inport argument) that is present on the Open vSwitch in‐
                     stance.

                     The microflow argument describes the  packet  whose  for‐
                     warding is to be simulated, in the syntax of an OVN logi‐
                     cal  expression,  as  described  in ovn-sb(5), to express
                     constraints. The parser  understands  prerequisites;  for
                     example, if the expression refers to ip4.src, there is no
                     need to explicitly state ip4 or eth.type == 0x800.

              connection-status
                     Show OVN SBDB connection status for the chassis.

              recompute
                     Trigger  a full compute iteration in ovn-controller based
                     on the contents of the Southbound database and local  OVS
                     database.

                     This  command  is  intended to use only in the event of a
                     bug in the  incremental  processing  engine  in  ovn-con‐‐
                     troller to avoid inconsistent states. It should therefore
                     be used with care as full recomputes are cpu intensive.

              sb-cluster-state-reset
                     Reset  southbound  database cluster status when databases
                     are destroyed and rebuilt.

                     If all databases in a clustered southbound  database  are
                     removed from disk, then the stored index of all databases
                     will  be reset to zero. This will cause ovn-controller to
                     be unable to read or write to  the  southbound  database,
                     because  it will always detect the data as stale. In such
                     a case, run this command so that ovn-controller will  re‐
                     set  its  local  index  so  that it can interact with the
                     southbound database again.

              debug/delay-nb-cfg-report seconds
                     This command is used to delay ovn-controller updating the
                     nb_cfg back to OVN_Southbound database.  This  is  useful
                     when  ovn-nbctl  --wait=hv  is used to measure end-to-end
                     latency in a large scale  environment.  See  ovn-nbctl(8)
                     for more details.

              lflow-cache/flush
                     Flushes the ovn-controller logical flow cache.

              lflow-cache/show-stats
                     Displays logical flow cache statistics: enabled/disabled,
                     per cache type entry counts.

              inc-engine/show-stats
                     Display  ovn-controller  engine counters. For each engine
                     node the following counters have been added:

                     •      recomputecomputeabort

              inc-engine/clear-stats
                     Reset ovn-controller engine counters.

OVN 22.03.8                     ovn-controller               ovn-controller(8)