Provided by: ovn-common_24.03.2-0ubuntu0.24.04.1_amd64 
NAME
ovn-appctl - utility for configuring running OVN daemons
SYNOPSIS
ovn-appctl [-target=target | -t target] [-T secs | -timeout=secs] command [arg...]
ovn-appctl -help
ovn-appctl -version
DESCRIPTION
OVN daemons accept certain commands at runtime to control their behavior and query their settings. Every
daemon accepts a common set of commands documented under COMMON COMMANDS below. Some daemons support
additional commands documented in their own manpages.
The ovn-appctl program provides a simple way to invoke these commands. The command to be sent is
specified on ovn-appctl’s command line as non-option arguments. ovn-appctl sends the command and prints
the daemon’s response on standard output.
ovn-ctl is exactly similar to Open vSwitch ovs-appctl utility.
COMMAND COMMANDS
Every OVN daemon supports a common set of commands, which are documented in this section.
General Commands
These commands display daemon-specific commands and the running version. Note that these commands are
different from the -help and -version options that return information about the ovn-appctl utility
itself.
list-commands
Lists the commands supported by the target.
version
Displays the version and compilation date of the target.
Logging Commands
OVN has several log levels. The highest-severity log level is:
off No message is ever logged at this level, so setting a logging destination’s log level to
off disables logging to that destination.
The following log levels, in order of descending severity, are available:
emer A major failure forced a process to abort.
err A high-level operation or a subsystem failed. Attention is warranted.
warn A low-level operation failed, but higher-level subsystems may be able to recover.
info Information that may be useful in retrospect when investigating a problem.
dbg Information useful only to someone with intricate knowledge of the system, or that would
commonly cause too-voluminous log output. Log messages at this level are not logged by
default.
Every OVN daemon supports the following commands for examining and adjusting log levels.
vlog/list
Lists the known logging modules and their current levels.
vlog/list-pattern
Lists logging pattern used for each destination.
vlog/set [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 ovn-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.
On Windows platform, syslog is accepted as a word and is only useful if the target
was started 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.
Case is not significant within spec.
vlog/set PATTERN:destination: pattern
Sets the log pattern for destination to pattern. Each time a message is logged to
destination, pattern determines the message’s formatting. Most characters in pattern are
copied literally to the log, but special escapes beginning with % are expanded as follows:
• %A : The name of the application logging the message, e.g. ovn-controller.
• %B : The RFC5424 syslog PRI of the message.
• %c : The name of the module (as shown by ovn-appctl -list) logging the message.
• %d : The current date and time in ISO 8601 format (YYYY-MM-DD HH:MM:SS).
• %d{format} : The current date and time in the specified format, which takes the same
format as the template argument to strftime(3). As an extension, any # characters in
format will be replaced by fractional seconds, e.g. use %H:%M:%S.### for the time to
the nearest millisecond. Sub-second times are only approximate and currently decimal
places after the third will always be reported as zero.
• %D : The current UTC date and time in ISO 8601 format (YYYY-MM-DD HH:MM:SS).
• %D{format} : The current UTC date and time in the specified format, which takes the
same format as the template argument to strftime(3). Supports the same extension for
sub-second resolution as %d{...}.
• %E : The hostname of the node running the application.
• %m : The message being logged.
• %N : A serial number for this message within this run of the program, as a decimal
number. The first message a program logs has serial number 1, the second one has
serial number 2, and so on.
• %n : A new-line.
• %p : The level at which the message is logged, e.g. DBG.
• %P : The program’s process ID (pid), as a decimal number.
• %r : The number of milliseconds elapsed from the start of the application to the
time the message was logged.
• %t : The subprogram name, that is, an identifying name for the process or thread
that emitted the log message, such as monitor for the process used for -monitor or
main for the primary process or thread in a program.
• %T : The subprogram name enclosed in parentheses, e.g. (monitor), or the empty
string for the primary process or thread in a program.
• %% : A literal %.
A few options may appear between the % and the format specifier character, in this order:
• - : Left justify the escape’s expansion within its field width. Right justification
is the default.
• - : Pad the field to the field width with 0s. Padding with spaces is the default.
width A number specifies the minimum field width. If the escape expands to fewer characters
than width then it is padded to fill the field width. (A field wider than width is not
truncated to fit.)
The default pattern for console and file output is %D{%Y-%m-%dT %H:%M:%SZ}|%05N|%c|%p|%m;
for syslog output, %05N|%c|%p|%m.
vlog/set 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.
vlog/close
Causes the daemon to close its log file, if it is open. (Use vlog/reopen to reopen it
later.)
vlog/reopen
Causes the daemon to close its log file, if it is open, and then reopen it. (This is useful
after rotating log files, to cause a new log file to be used.)
This has no effect if the target application was not invoked with the --log-file option.
OPTIONS
-h
--help
Prints a brief help message to the console.
-V
--version
Prints version information to the console.