ovn-appctl(8) OVN Manual ovn-appctl(8)
NAME
ovn-appctl - utility for configuring running OVN daemons
SYNOPSIS
ovn-appctl [-target=target | -t target] [-T secs | -timeout=secs] com���
mand [arg...]
ovn-appctl -help
ovn-appctl -version
DESCRIPTION
OVN daemons accept certain commands at runtime to control their behav‐
ior and query their settings. Every daemon accepts a common set of com‐
mands documented under COMMON COMMANDS below. Some daemons support ad‐
ditional 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 dae‐
mon’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 docu‐
mented in this section.
General Commands
These commands display daemon-specific commands and the running ver‐
sion. Note that these commands are different from the -help and -ver‐
sion options that return information about the ovn-appctl utility it‐
self.
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 avail‐
able:
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 inves‐
tigating a problem.
dbg Information useful only to someone with intricate knowl‐
edge of the system, or that would commonly cause too-vo‐
luminous log output. Log messages at this level are not
logged by default.
Every OVN daemon supports the following commands for examining and ad‐
justing 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 deter‐
mines the message’s formatting. Most characters in pat‐
tern are copied literally to the log, but special escapes
beginning with % are expanded as follows:
• %A : The name of the application logging the mes‐
sage, e.g. ovn-controller.
• %B : The RFC5424 syslog PRI of the message.
• %c : The name of the module (as shown by ovn-ap‐
pctl -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 exten‐
sion, 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 applica‐
tion.
• %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 pri‐
mary 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 in‐
voked with the --log-file option.
OPTIONS
-h
--help
Prints a brief help message to the console.
-V
--version
Prints version information to the console.
OVN 22.03.8 ovn-appctl ovn-appctl(8)