Provided by: ovn-common_25.03.0-1_amd64 bug

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 pidfile already exists and is locked by
              a running process, the daemon 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  (SIGABRT,  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 functions without it.

       --no-chdir
              By default, when --detach is specified, the daemon changes its current working  directory  to  the
              root  directory  after  it  detaches.  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 additional 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 specified module.

            •      syslog, console, or file, to limit the log level change to only to the  system  log,  to  the
                   console,  or  to  a  file,  respectively.  (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 --verbose=dbg.

       -vPATTERN:destination:pattern
       --verbose=PATTERN:destination:pattern
            Sets the log pattern for destination to pattern. Refer to ovs-appctl(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 local0 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 /var/log/ovn/program.log.

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

       --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 message 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 possible 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 address 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 extra
                   precaution needs to be taken into account, for example, syslog daemon needs to be  configured
                   to  listen  on  the  specified  UDP port, accidental iptables rules could be interfering with
                   local syslog traffic and there are some security 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 variable; if it is unset, the default is
            libc.

   PKI Options
       PKI  configuration  is  required  in  order  to  use  SSL/TLS  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/TLS
                   connections.

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

              -C cacert.pem
              --ca-cert=cacert.pem
                   Specifies  a  PEM  file containing the CA certificate for verifying certificates presented to
                   this program by SSL/TLS peers. (This may be the same certificate that SSL/TLS  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/TLS 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 executable will attempt to obtain the CA certificate from the SSL/TLS peer
                     on its first SSL/TLS connection and save it to the named PEM file. If it is successful,  it
                     will  immediately  drop  the  connection  and  reconnect,  and  from  then  on  all SSL/TLS
                     connections must be authenticated by a  certificate  signed  by  the  CA  certificate  thus
                     obtained.

                     This  option  exposes  the  SSL/TLS  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/TLS peer sends its CA  certificate  as  part  of  the
                     SSL/TLS  certificate  chain.  SSL/TLS  protocols  do  not require the server to send the CA
                     certificate.

                     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/TLS
                     peers.  peer-cacert.pem  should  be  the  CA  certificate  used  to  sign the program’s own
                     certificate, 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/TLS 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/TLS connection.

   Other Options
       --unixctl=socket
              Sets  the name of the control socket on which program listens for runtime management commands (see
              RUNTIME MANAGEMENT COMMANDS, below). If socket does  not  begin  with  /,  it  is  interpreted  as
              relative  to  . If --unixctl is not used at all, the default socket is /program.pid.ctl, where pid
              is program’s process ID.

              On Windows a local named pipe is used to listen for runtime management commands. A file is created
              in the absolute path as pointed by socket or if --unixctl is not used at all, a file is created as
              program in the configured OVS_RUNDIR directory. The file exists just to mimic the  behavior  of  a
              Unix domain socket.

              Specifying none for socket disables the control socket feature.

       -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
       overridden by specifying the ovs-database argument as an OVSDB active or passive  connection  method,  as
       described in ovsdb(7).

       ovn-controller  assumes  it  gets  configuration  information from the following 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 directly 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.  Note  that  the  chassis  name  can  also  be  provided  via the
                     system-id-override file in the local OVN "etc" directory or via the -n command-line option.
                     The following precedence is used: first, the command-line option is read; if  not  present,
                     the  system-id-override  file  is  read;  if  not  present, then the name configured in the
                     database is used.

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

              external_ids:ovn-bridge
                     The integration bridge to which logical ports are attached. The default is br-int. If  this
                     bridge does not exist when ovn-controller starts, it will be created automatically with the
                     default  configuration suggested in ovn-architecture(7). When more than one controllers are
                     running on the same host, external_ids:ovn-bridge-CHASSIS_NAME should be set  for  each  of
                     them,  pointing  to a unique bridge. This is required to avoid controllers stepping on each
                     others’ feet.

              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 configured value. If this option is not set, then ovn-controller 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 monitor all records of tables in the
                     OVN_Southbound. If this option is set to false, ovn-controller will  conditionally  monitor
                     only the records that are needed for the local 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 the OVN_Southbound database, which would save  the  overhead
                     of  conditions  processing,  especially  for  server  side.  Typically,  set it to true for
                     environments where all workloads need to be reachable from each other.

                     NOTE: for efficiency and scalability in  common  scenarios  ovn-controller  unconditionally
                     monitors  all  sub-ports  (ports  with  parent_port  set) regardless of the ovn-monitor-all
                     value.

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

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

                     stt tunnel type is deprecated.

                     Due to the limited amount of  metadata  in  vxlan,  the  capabilities  and  performance  of
                     connected gateways and hypervisors 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 external_ids:ovn-encap-type. Multiple encapsulation IPs may be specified  with
                     a comma-separated list.

                     In scenarios where multiple encapsulation IPs are present, distinct tunnels are established
                     for   each   remote   chassis.   These   tunnels   are  differentiated  by  setting  unique
                     options:local_ip and options:remote_ip values in the tunnel interface. When transmitting  a
                     packet   to   a   remote   chassis,   the   selection   of   local_ip   is  guided  by  the
                     Interface:external_ids:encap-ip from the local OVSDB, corresponding to the VIF  originating
                     the  packet,  if  specified. The Interface:external_ids:encap-ip setting of the VIF is also
                     populated to the  Port_Binding  table  in  the  OVN  SB  database  via  the  encap  column.
                     Consequently,  when  a  remote  chassis needs to send a packet to a port-binding associated
                     with this VIF, it utilizes the tunnel with the appropriate options:remote_ip  that  matches
                     the  ip  in  Port_Binding:encap. This mechanism is particularly beneficial for chassis with
                     multiple physical interfaces designated for tunneling, where each  interface  is  optimized
                     for handling specific traffic associated with particular VIFs.

              external_ids:ovn-encap-ip-default
                     When ovn-encap-ip contains multiple IPs, this field indicates the default one.

              external_ids:ovn-encap-df_default
                     indicates  the DF flag handling of the encapulation. Set to true to set the DF flag for new
                     data paths or false to clear the DF flag.

              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 network names
                     to two ovs bridges would be: physnet1: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 default 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  distributed
                     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 internal 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 environments, 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 upgrade/restart, while setting it  too
                     big  may  result  in unnecessary 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 OpenFlow 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 configuration 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 enable/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 maximum number  of  logical  flow  cache
                     entries  ovn-controller  may  create when the logical flow cache is enabled. By default the
                     size of the cache is unlimited.

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

              external_ids:ovn-trim-limit-lflow-cache
                     When used, this configuration value sets the minimum number 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 performed. E.g.,
                     if the trim watermark percentage is set to 50%, automatic memory trimming happens only when
                     the number 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 operation 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: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.

              external_ids:arp-nd-max-timeout-sec
                     When used, this configuration value specifies the maximum timeout (in seconds) between  two
                     consecutive  ARP/ND  packets  sent  by  ovn-controller to resolve ECMP nexthop mac address.
                     ovn-controller    by    default    continuously    sends    ARP/ND     packets.     Setting
                     external_ids:arp-nd-max-timeout-sec  allows  to  cap  for  the  exponential backoff used by
                     ovn-controller
                      to send ARPs/NDs packets.

              external_ids:ovn-bridge-remote
                     Connection to the OVN management bridge in OvS. It defaults to  unix:br-int.mgmt  when  not
                     specified.

              external_ids:ovn-bridge-remote-probe-interval
                     The  inactivity  probe  interval  of  the  connection  to  the  OVN  management  bridge, in
                     milliseconds. It defaults to zero. If the value is zero, it disables the inactivity probe.

              external_ids:dynamic-routing-port-mapping
                     This setting  works  together  with  the  Northbound  dynamic-routing-port-name  option  on
                     Logical_Router_Ports. See the ovn-nb(5) for more details.

       Most  of  configuration  options  listed  above  can  also  be  set  for  a  particular chassis name (see
       external_ids:system-id     for    more    information).    This    can    be    achieved    by    setting
       external_ids:option-[chassis]      instead      of      external_ids:option.     For     example,     set
       external_ids:ovn-encap-ip-otherhv to use a particular  IP  address  for  the  controller  instance  named
       otherhv. Name specific configuration options always override any global options set in the database.

       Chassis-specific  configuration options in the database plus the ability to configure the chassis name to
       use via the system-id-override file or command line allows to run multiple ovn-controller instances  with
       unique chassis names on the same host using the same vswitchd instance. This may be useful when running a
       hybrid setup with more than one CMS managing ports on the host, or to use different datapath types on the
       same  host.  Also  note  that this ability is highly experimental and has known limitations (for example,
       stateful ACLs are not supported). Use at your own risk.

       ovn-controller reads the following values from the Open_vSwitch database 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/TLS configuration used for connecting to  the  OVN  southbound
                     database  server when an SSL/TLS connection type is configured via external_ids:ovn-remote.
                     Note that this SSL/TLS configuration can also be provided  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-range in the Open_vSwitch table
                     The  presence  of  this  key  identifies  a  minimum  and  maximum  values  for ct-zone ids
                     dynamically selected by ovn-controller (boundaries are  included  in  the  range).  Minimum
                     value is 1 while maximum value is 65535.

              external_ids:ct-zone-* in the Bridge table
                     Logical ports and gateway routers are assigned a connection tracking zone by ovn-controller
                     for  stateful  services.  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 external_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 different bridge, with the same external_ids:ovn-localnet-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  logical  port.
                     Its  value  is  the  name  of  the  logical  port  with type set to l2gateway that the port
                     implements. See external_ids:ovn-bridge-mappings, above, for more information.

                     Each l2gateway logical port is implemented as a pair of patch ports, one in the integration
                     bridge, one in a different bridge, with the same external_ids:ovn-l2gateway-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 particular 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_Southbound.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 corresponding 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-installed-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 automatically 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-controller.

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  instance.  microflow  must  contain  an
                     ingress logical port (inport argument) that is present on the Open vSwitch instance.

                     The  microflow  argument  describes  the packet whose forwarding is to be simulated, in the
                     syntax of an OVN logical 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-controller  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 reset 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:

                     •      recomputecomputecancel

              inc-engine/show-stats engine_node_name counter_name
                     Display   the   ovn-controller   engine  counter(s)  for  the  specified  engine_node_name.
                     counter_name is optional and can be one of recompute, compute or cancel.

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

OVN 25.03.0                                      ovn-controller                                ovn-controller(8)