ovs-appctl(8) Open vSwitch Manual ovs-appctl(8)
NAME
ovs-appctl - utility for configuring running Open vSwitch daemons
SYNOPSIS
ovs-appctl [--target=target | -t target] command [arg...]
ovs-appctl --help
ovs-appctl --version
DESCRIPTION
Open vSwitch 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.
ovs-vswitchd in particular accepts a number of additional commands doc‐
umented in ovs-vswitchd(8).
The ovs-appctl program provides a simple way to invoke these commands.
The command to be sent is specified on ovs-appctl's command line as
non-option arguments. ovs-appctl sends the command and prints the dae‐
mon's response on standard output.
In normal use only a single option is accepted:
-t target
--target=target
Tells ovs-appctl which daemon to contact.
If target begins with / it must name a Unix domain socket on
which an Open vSwitch daemon is listening for control channel
connections. By default, each daemon listens on a Unix domain
socket named /var/run/openvswitch/program.pid.ctl, where program
is the program's name and pid is its process ID. For example,
if ovs-vswitchd has PID 123, it would listen on /var/run/open‐
vswitch/ovs-vswitchd.123.ctl.
Otherwise, ovs-appctl looks for a pidfile, that is, a file whose
contents are the process ID of a running process as a decimal
number, named /var/run/openvswitch/target.pid. (The --pidfile
option makes an Open vSwitch daemon create a pidfile.)
ovs-appctl reads the pidfile, then looks for a Unix socket named
/var/run/openvswitch/target.pid.ctl, where pid is replaced by
the process ID read from the pidfile, and uses that file as if
it had been specified directly as the target.
On Windows, target can be an absolute path to a file that con‐
tains a localhost TCP port on which an Open vSwitch daemon is
listening for control channel connections. By default, each dae‐
mon writes the TCP port on which it is listening for control
connection into the file program.ctl located inside the config‐
ured OVS_RUNDIR directory. If target is not an absolute path,
ovs-appctl looks for a file named target.ctl in the configured
OVS_RUNDIR directory.
The default target is ovs-vswitchd.
COMMON COMMANDS
Every Open vSwitch daemon supports a common set of commands, which are
documented 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
--version options that return information about the ovs-appctl utility
itself.
list-commands
Lists the commands supported by the target.
version
Displays the version and compilation date of the target.
LOGGING COMMANDS
Open vSwitch 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 destina‐
tion.
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 war‐
ranted.
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 out‐
put. Log messages at this level are not logged by default.
Every Open vSwitch 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 com‐
mand 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.
On Windows platform, syslog is accepted as a word and is
only useful if the target was started with the --sys‐
log-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.
Regardless of the log levels set for file, logging to a file
will not take place unless the target application was invoked
with the --log-file option.
For compatibility with older versions of OVS, any is accepted as
a word but has no effect.
vlog/set PATTERN:destination:pattern
Sets the log pattern for destination to pattern. Each time a
message is logged to destination, pattern determines the mes‐
sage's formatting. Most characters in pattern are copied liter‐
ally to the log, but special escapes beginning with % are
expanded as follows:
%A The name of the application logging the message, e.g.
ovs-vswitchd.
%B The RFC5424 syslog PRI of the message.
%c The name of the module (as shown by ovs-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 strf‐
time(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 deci‐
mal 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 pro‐
gram 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. (moni‐
tor), 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.
0 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.
Daemons written in Python (e.g. ovs-xapi-sync, ovs-moni‐
tor-ipsec) do not allow control over the log pattern.
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/reopen
Causes the daemon to close and reopen its log file. (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.
SEE ALSO
ovs-appctl can control all Open vSwitch daemons, including:
ovs-vswitchd(8), and ovsdb-server(8).
Open vSwitch 2.4.90 ovs-appctl(8)