Configuration File

Configuration File

The Supervisor configuration file is conventionally named supervisord.conf. It is used by both supervisord and supervisorctl. If either application is started without the -c option (the option which is used to tell the application the configuration filename explicitly), the application will look for a file named supervisord.conf within the following locations, in the specified order. It will use the first file it finds.

../etc/supervisord.conf (Relative to the executable)
../supervisord.conf (Relative to the executable)
$CWD/supervisord.conf
$CWD/etc/supervisord.conf
/etc/supervisord.conf
/etc/supervisor/supervisord.conf (since Supervisor 3.3.0)

Note

Many versions of Supervisor packaged for Debian and Ubuntu included a patch that added /etc/supervisor/supervisord.conf to the search paths. The first PyPI package of Supervisor to include it was Supervisor 3.3.0.

File Format

supervisord.conf is a Windows-INI-style (Python ConfigParser) file. It has sections (each denoted by a [header]) and key / value pairs within the sections. The sections and their allowable values are described below.

Environment Variables

Environment variables that are present in the environment at the time that supervisord is started can be used in the configuration file using the Python string expression syntax %(ENV_X)s:

[program:example]
command=/usr/bin/example --loglevel=%(ENV_LOGLEVEL)s

In the example above, the expression %(ENV_LOGLEVEL)s would be expanded to the value of the environment variable LOGLEVEL.

Note

In Supervisor 3.2 and later, %(ENV_X)s expressions are supported in all options. In prior versions, some options support them, but most do not. See the documentation for each option below.

[unix_http_server] Section Settings

The supervisord.conf file contains a section named [unix_http_server] under which configuration parameters for an HTTP server that listens on a UNIX domain socket should be inserted. If the configuration file has no [unix_http_server] section, a UNIX domain socket HTTP server will not be started. The allowable configuration values are as follows.

[unix_http_server] Section Values

file

A path to a UNIX domain socket on which supervisor will listen for HTTP/XML-RPC requests. supervisorctl uses XML-RPC to communicate with supervisord over this port. This option can include the value %(here)s, which expands to the directory in which the supervisord configuration file was found.

Default: None.

Required: No.

Introduced: 3.0

Warning

The example configuration output by echo_supervisord_conf uses /tmp/supervisor.sock as the socket file. That path is an example only and will likely need to be changed to a location more appropriate for your system. Some systems periodically delete older files in /tmp. If the socket file is deleted, supervisorctl will be unable to connect to supervisord.

chmod

Change the UNIX permission mode bits of the UNIX domain socket to this value at startup.

Default: 0700

Required: No.

Introduced: 3.0

chown

Change the user and group of the socket file to this value. May be a UNIX username (e.g. chrism) or a UNIX username and group separated by a colon (e.g. chrism:wheel).

Default: Use the username and group of the user who starts supervisord.

Required: No.

Introduced: 3.0

username

The username required for authentication to this HTTP server.

Default: No username required.

Required: No.

Introduced: 3.0

password

The password required for authentication to this HTTP server. This can be a cleartext password, or can be specified as a SHA-1 hash if prefixed by the string {SHA}. For example, {SHA}82ab876d1387bfafe46cc1c8a2ef074eae50cb1d is the SHA-stored version of the password “thepassword”.

Note that hashed password must be in hex format.

Default: No password required.

Required: No.

Introduced: 3.0

[unix_http_server] Section Example

[unix_http_server]
file = /tmp/supervisor.sock
chmod = 0777
chown= nobody:nogroup
username = user
password = 123

[inet_http_server] Section Settings

The supervisord.conf file contains a section named [inet_http_server] under which configuration parameters for an HTTP server that listens on a TCP (internet) socket should be inserted. If the configuration file has no [inet_http_server] section, an inet HTTP server will not be started. The allowable configuration values are as follows.

Warning

The inet HTTP server is not enabled by default. If you choose to enable it, please read the following security warning. The inet HTTP server is intended for use within a trusted environment only. It should only be bound to localhost or only accessible from within an isolated, trusted network. The inet HTTP server does not support any form of encryption. The inet HTTP server does not use authentication by default (see the username= and password= options). The inet HTTP server can be controlled remotely from supervisorctl. It also serves a web interface that allows subprocesses to be started or stopped, and subprocess logs to be viewed. Never expose the inet HTTP server to the public internet.

[inet_http_server] Section Values

port

A TCP host:port value or (e.g. 127.0.0.1:9001) on which supervisor will listen for HTTP/XML-RPC requests. supervisorctl will use XML-RPC to communicate with supervisord over this port. To listen on all interfaces in the machine, use :9001 or *:9001. Please read the security warning above.

Default: No default.

Required: Yes.

Introduced: 3.0

username

The username required for authentication to this HTTP server.

Default: No username required.

Required: No.

Introduced: 3.0

password

The password required for authentication to this HTTP server. This can be a cleartext password, or can be specified as a SHA-1 hash if prefixed by the string {SHA}. For example, {SHA}82ab876d1387bfafe46cc1c8a2ef074eae50cb1d is the SHA-stored version of the password “thepassword”.

Note that hashed password must be in hex format.

Default: No password required.

Required: No.

Introduced: 3.0

[inet_http_server] Section Example

[inet_http_server]
port = 127.0.0.1:9001
username = user
password = 123

[supervisord] Section Settings

The supervisord.conf file contains a section named [supervisord] in which global settings related to the supervisord process should be inserted. These are as follows.

[supervisord] Section Values

logfile

The path to the activity log of the supervisord process. This option can include the value %(here)s, which expands to the directory in which the supervisord configuration file was found.

Note

If logfile is set to a special file like /dev/stdout that is not seekable, log rotation must be disabled by setting logfile_maxbytes = 0.

Default: $CWD/supervisord.log

Required: No.

Introduced: 3.0

logfile_maxbytes

The maximum number of bytes that may be consumed by the activity log file before it is rotated (suffix multipliers like “KB”, “MB”, and “GB” can be used in the value). Set this value to 0 to indicate an unlimited log size.

Default: 50MB

Required: No.

Introduced: 3.0

logfile_backups

The number of backups to keep around resulting from activity log file rotation. If set to 0, no backups will be kept.

Default: 10

Required: No.

Introduced: 3.0

loglevel

The logging level, dictating what is written to the supervisord activity log. One of critical, error, warn, info, debug, trace, or blather. Note that at log level debug, the supervisord log file will record the stderr/stdout output of its child processes and extended info info about process state changes, which is useful for debugging a process which isn’t starting properly. See also: Activity Log Levels.

Default: info

Required: No.

Introduced: 3.0

pidfile

The location in which supervisord keeps its pid file. This option can include the value %(here)s, which expands to the directory in which the supervisord configuration file was found.

Default: $CWD/supervisord.pid

Required: No.

Introduced: 3.0

umask

The umask of the supervisord process.

Default: 022

Required: No.

Introduced: 3.0

nodaemon

If true, supervisord will start in the foreground instead of daemonizing.

Default: false

Required: No.

Introduced: 3.0

silent

If true and not daemonized, logs will not be directed to stdout.

Default: false

Required: No.

Introduced: 4.2.0

minfds

The minimum number of file descriptors that must be available before supervisord will start successfully. A call to setrlimit will be made to attempt to raise the soft and hard limits of the supervisord process to satisfy minfds. The hard limit may only be raised if supervisord is run as root. supervisord uses file descriptors liberally, and will enter a failure mode when one cannot be obtained from the OS, so it’s useful to be able to specify a minimum value to ensure it doesn’t run out of them during execution. These limits will be inherited by the managed subprocesses. This option is particularly useful on Solaris, which has a low per-process fd limit by default.

Default: 1024

Required: No.

Introduced: 3.0

minprocs

The minimum number of process descriptors that must be available before supervisord will start successfully. A call to setrlimit will be made to attempt to raise the soft and hard limits of the supervisord process to satisfy minprocs. The hard limit may only be raised if supervisord is run as root. supervisord will enter a failure mode when the OS runs out of process descriptors, so it’s useful to ensure that enough process descriptors are available upon supervisord startup.

Default: 200

Required: No.

Introduced: 3.0

nocleanup

Prevent supervisord from clearing any existing AUTO child log files at startup time. Useful for debugging.

Default: false

Required: No.

Introduced: 3.0

childlogdir

The directory used for AUTO child log files. This option can include the value %(here)s, which expands to the directory in which the supervisord configuration file was found.

Default: value of Python’s tempfile.get_tempdir()

Required: No.

Introduced: 3.0

user

Instruct supervisord to switch users to this UNIX user account before doing any meaningful processing. The user can only be switched if supervisord is started as the root user.

Default: do not switch users

Required: No.

Introduced: 3.0

Changed: 3.3.4. If supervisord can’t switch to the specified user, it will write an error message to stderr and then exit immediately. In earlier versions, it would continue to run but would log a message at the critical level.

[supervisord] Section Example

[supervisord]
logfile = /tmp/supervisord.log
logfile_maxbytes = 50MB
logfile_backups=10
loglevel = info
pidfile = /tmp/supervisord.pid
nodaemon = false
minfds = 1024
minprocs = 200
umask = 022
user = chrism
identifier = supervisor
directory = /tmp
nocleanup = true
childlogdir = /tmp
strip_ansi = false
environment = KEY1="value1",KEY2="value2"

[supervisorctl] Section Settings

The configuration file may contain settings for the supervisorctl interactive shell program. These options are listed below.

[supervisorctl] Section Values

serverurl

The URL that should be used to access the supervisord server, e.g. http://localhost:9001. For UNIX domain sockets, use unix:///absolute/path/to/file.sock.

Default: http://localhost:9001

Required: No.

Introduced: 3.0

username

The username to pass to the supervisord server for use in authentication. This should be same as username from the supervisord server configuration for the port or UNIX domain socket you’re attempting to access.

Default: No username

Required: No.

Introduced: 3.0

password

The password to pass to the supervisord server for use in authentication. This should be the cleartext version of password from the supervisord server configuration for the port or UNIX domain socket you’re attempting to access. This value cannot be passed as a SHA hash. Unlike other passwords specified in this file, it must be provided in cleartext.

Default: No password

Required: No.

Introduced: 3.0

prompt

String used as supervisorctl prompt.

Default: supervisor

Required: No.

Introduced: 3.0

history_file

A path to use as the readline persistent history file. If you enable this feature by choosing a path, your supervisorctl commands will be kept in the file, and you can use readline (e.g. arrow-up) to invoke commands you performed in your last supervisorctl session.

Default: No file

Required: No.

Introduced: 3.0a5

[supervisorctl] Section Example

[supervisorctl]
serverurl = unix:///tmp/supervisor.sock
username = chris
password = 123
prompt = mysupervisor

[program:x] Section Settings

The configuration file must contain one or more program sections in order for supervisord to know which programs it should start and control. The header value is composite value. It is the word “program”, followed directly by a colon, then the program name. A header value of [program:foo] describes a program with the name of “foo”. The name is used within client applications that control the processes that are created as a result of this configuration. It is an error to create a program section that does not have a name. The name must not include a colon character or a bracket character. The value of the name is used as the value for the %(program_name)s string expression expansion within other values where specified.

Note

A [program:x] section actually represents a “homogeneous process group” to supervisor (as of 3.0). The members of the group are defined by the combination of the numprocs and process_name parameters in the configuration. By default, if numprocs and process_name are left unchanged from their defaults, the group represented by [program:x] will be named x and will have a single process named x in it. This provides a modicum of backwards compatibility with older supervisor releases, which did not treat program sections as homogeneous process group definitions.

But for instance, if you have a [program:foo] section with a numprocs of 3 and a process_name expression of %(program_name)s_%(process_num)02d, the “foo” group will contain three processes, named foo_00, foo_01, and foo_02. This makes it possible to start a number of very similar processes using a single [program:x] section. All logfile names, all environment strings, and the command of programs can also contain similar Python string expressions, to pass slightly different parameters to each process.

[program:x] Section Values

command

The command that will be run when this program is started. The command can be either absolute (e.g. /path/to/programname) or relative (e.g. programname). If it is relative, the supervisord’s environment $PATH will be searched for the executable. Programs can accept arguments, e.g. /path/to/program foo bar. The command line can use double quotes to group arguments with spaces in them to pass to the program, e.g. /path/to/program/name -p “foo bar”. Note that the value of command may include Python string expressions, e.g. /path/to/programname —port=80%(process_num)02d might expand to /path/to/programname —port=8000 at runtime. String expressions are evaluated against a dictionary containing the keys group_name, host_node_name, program_name, process_num, numprocs, here (the directory of the supervisord config file), and all supervisord’s environment variables prefixed with ENV_. Controlled programs should themselves not be daemons, as supervisord assumes it is responsible for daemonizing its subprocesses (see Nondaemonizing of Subprocesses).

Note

The command will be truncated if it looks like a config file comment, e.g. command=bash -c ‘foo ; bar’ will be truncated to command=bash -c ‘foo. Quoting will not prevent this behavior, since the configuration file reader does not parse the command like a shell would.

Default: No default.

Required: Yes.

Introduced: 3.0

Changed: 4.2.0. Added support for the numprocs expansion.

process_name

A Python string expression that is used to compose the supervisor process name for this process. You usually don’t need to worry about setting this unless you change numprocs. The string expression is evaluated against a dictionary that includes group_name, host_node_name, process_num, program_name, and here (the directory of the supervisord config file).

Default: %(program_name)s

Required: No.

Introduced: 3.0

numprocs

Supervisor will start as many instances of this program as named by numprocs. Note that if numprocs > 1, the process_name expression must include %(process_num)s (or any other valid Python string expression that includes process_num) within it.

Default: 1

Required: No.

Introduced: 3.0

numprocs_start

An integer offset that is used to compute the number at which numprocs starts.

Default: 0

Required: No.

Introduced: 3.0

priority

The relative priority of the program in the start and shutdown ordering. Lower priorities indicate programs that start first and shut down last at startup and when aggregate commands are used in various clients (e.g. “start all”/”stop all”). Higher priorities indicate programs that start last and shut down first.

Default: 999

Required: No.

Introduced: 3.0

autostart

If true, this program will start automatically when supervisord is started.

Default: true

Required: No.

Introduced: 3.0

startsecs

The total number of seconds which the program needs to stay running after a startup to consider the start successful (moving the process from the STARTING state to the RUNNING state). Set to 0 to indicate that the program needn’t stay running for any particular amount of time.

Note

Even if a process exits with an “expected” exit code (see exitcodes), the start will still be considered a failure if the process exits quicker than startsecs.

Default: 1

Required: No.

Introduced: 3.0

startretries

The number of serial failure attempts that supervisord will allow when attempting to start the program before giving up and putting the process into an FATAL state. See Process States for explanation of the FATAL state.

Default: 3

Required: No.

Introduced: 3.0

autorestart

Specifies if supervisord should automatically restart a process if it exits when it is in the RUNNING state. May be one of false, unexpected, or true. If false, the process will not be autorestarted. If unexpected, the process will be restarted when the program exits with an exit code that is not one of the exit codes associated with this process’ configuration (see exitcodes). If true, the process will be unconditionally restarted when it exits, without regard to its exit code.

Note

autorestart controls whether supervisord will autorestart a program if it exits after it has successfully started up (the process is in the RUNNING state).

supervisord has a different restart mechanism for when the process is starting up (the process is in the STARTING state). Retries during process startup are controlled by startsecs and startretries.

Default: unexpected

Required: No.

Introduced: 3.0

exitcodes

The list of “expected” exit codes for this program used with autorestart. If the autorestart parameter is set to unexpected, and the process exits in any other way than as a result of a supervisor stop request, supervisord will restart the process if it exits with an exit code that is not defined in this list.

Default: 0

Required: No.

Introduced: 3.0

Note

In Supervisor versions prior to 4.0, the default was 0,2. In Supervisor 4.0, the default was changed to 0.

stopsignal

The signal used to kill the program when a stop is requested. This can be any of TERM, HUP, INT, QUIT, KILL, USR1, or USR2.

Default: TERM

Required: No.

Introduced: 3.0

stopwaitsecs

The number of seconds to wait for the OS to return a SIGCHLD to supervisord after the program has been sent a stopsignal. If this number of seconds elapses before supervisord receives a SIGCHLD from the process, supervisord will attempt to kill it with a final SIGKILL.

Default: 10

Required: No.

Introduced: 3.0

stopasgroup

If true, the flag causes supervisor to send the stop signal to the whole process group and implies killasgroup is true. This is useful for programs, such as Flask in debug mode, that do not propagate stop signals to their children, leaving them orphaned.

Default: false

Required: No.

Introduced: 3.0b1

killasgroup

If true, when resorting to send SIGKILL to the program to terminate it send it to its whole process group instead, taking care of its children as well, useful e.g with Python programs using multiprocessing.

Default: false

Required: No.

Introduced: 3.0a11

user

Instruct supervisord to use this UNIX user account as the account which runs the program. The user can only be switched if supervisord is run as the root user. If supervisord can’t switch to the specified user, the program will not be started.

Note

The user will be changed using setuid only. This does not start a login shell and does not change environment variables like USER or HOME. See Subprocess Environment for details.

Default: Do not switch users

Required: No.

Introduced: 3.0

redirect_stderr

If true, cause the process’ stderr output to be sent back to supervisord on its stdout file descriptor (in UNIX shell terms, this is the equivalent of executing /the/program 2>&1).

Note

Do not set redirect_stderr=true in an [eventlistener:x] section. Eventlisteners use stdout and stdin to communicate with supervisord. If stderr is redirected, output from stderr will interfere with the eventlistener protocol.

Default: false

Required: No.

Introduced: 3.0, replaces 2.0’s log_stdout and log_stderr

stdout_logfile

Put process stdout output in this file (and if redirect_stderr is true, also place stderr output in this file). If stdout_logfile is unset or set to AUTO, supervisor will automatically choose a file location. If this is set to NONE, supervisord will create no log file. AUTO log files and their backups will be deleted when supervisord restarts. The stdout_logfile value can contain Python string expressions that will evaluated against a dictionary that contains the keys group_name, host_node_name, process_num, program_name, and here (the directory of the supervisord config file).

Note

It is not possible for two processes to share a single log file (stdout_logfile) when rotation (stdout_logfile_maxbytes) is enabled. This will result in the file being corrupted.

Note

If stdout_logfile is set to a special file like /dev/stdout that is not seekable, log rotation must be disabled by setting stdout_logfile_maxbytes = 0.

Default: AUTO

Required: No.

Introduced: 3.0, replaces 2.0’s logfile

stdout_logfile_maxbytes

The maximum number of bytes that may be consumed by stdout_logfile before it is rotated (suffix multipliers like “KB”, “MB”, and “GB” can be used in the value). Set this value to 0 to indicate an unlimited log size.

Default: 50MB

Required: No.

Introduced: 3.0, replaces 2.0’s logfile_maxbytes

stdout_logfile_backups

The number of stdout_logfile backups to keep around resulting from process stdout log file rotation. If set to 0, no backups will be kept.

Default: 10

Required: No.

Introduced: 3.0, replaces 2.0’s logfile_backups

stdout_capture_maxbytes

Max number of bytes written to capture FIFO when process is in “stdout capture mode” (see Capture Mode). Should be an integer (suffix multipliers like “KB”, “MB” and “GB” can used in the value). If this value is 0, process capture mode will be off.

Default: 0

Required: No.

Introduced: 3.0

stdout_events_enabled

If true, PROCESS_LOG_STDOUT events will be emitted when the process writes to its stdout file descriptor. The events will only be emitted if the file descriptor is not in capture mode at the time the data is received (see Capture Mode).

Default: 0

Required: No.

Introduced: 3.0a7

stdout_syslog

If true, stdout will be directed to syslog along with the process name.

Default: False

Required: No.

Introduced: 4.0.0

stderr_logfile

Put process stderr output in this file unless redirect_stderr is true. Accepts the same value types as stdout_logfile and may contain the same Python string expressions.

Note

It is not possible for two processes to share a single log file (stderr_logfile) when rotation (stderr_logfile_maxbytes) is enabled. This will result in the file being corrupted.

Note

If stderr_logfile is set to a special file like /dev/stderr that is not seekable, log rotation must be disabled by setting stderr_logfile_maxbytes = 0.

Default: AUTO

Required: No.

Introduced: 3.0

stderr_logfile_maxbytes

The maximum number of bytes before logfile rotation for stderr_logfile. Accepts the same value types as stdout_logfile_maxbytes.

Default: 50MB

Required: No.

Introduced: 3.0

stderr_logfile_backups

The number of backups to keep around resulting from process stderr log file rotation. If set to 0, no backups will be kept.

Default: 10

Required: No.

Introduced: 3.0

stderr_capture_maxbytes

Max number of bytes written to capture FIFO when process is in “stderr capture mode” (see Capture Mode). Should be an integer (suffix multipliers like “KB”, “MB” and “GB” can used in the value). If this value is 0, process capture mode will be off.

Default: 0

Required: No.

Introduced: 3.0

stderr_events_enabled

If true, PROCESS_LOG_STDERR events will be emitted when the process writes to its stderr file descriptor. The events will only be emitted if the file descriptor is not in capture mode at the time the data is received (see Capture Mode).

Default: false

Required: No.

Introduced: 3.0a7

stderr_syslog

If true, stderr will be directed to syslog along with the process name.

Default: False

Required: No.

Introduced: 4.0.0

environment

A list of key/value pairs in the form KEY=”val”,KEY2=”val2” that will be placed in the child process’ environment. The environment string may contain Python string expressions that will be evaluated against a dictionary containing group_name, host_node_name, process_num, program_name, and here (the directory of the supervisord config file). Values containing non-alphanumeric characters should be quoted (e.g. KEY=”val:123”,KEY2=”val,456”). Otherwise, quoting the values is optional but recommended. Note that the subprocess will inherit the environment variables of the shell used to start “supervisord” except for the ones overridden here. See Subprocess Environment.

Default: No extra environment

Required: No.

Introduced: 3.0

[program:x] Section Example

[program:cat]
command=/bin/cat
process_name=%(program_name)s
numprocs=1
directory=/tmp
umask=022
priority=999
autostart=true
autorestart=unexpected
startsecs=10
startretries=3
exitcodes=0
stopsignal=TERM
stopwaitsecs=10
stopasgroup=false
killasgroup=false
user=chrism
redirect_stderr=false
stdout_logfile=/a/path
stdout_logfile_maxbytes=1MB
stdout_logfile_backups=10
stdout_capture_maxbytes=1MB
stdout_events_enabled=false
stderr_logfile=/a/path
stderr_logfile_maxbytes=1MB
stderr_logfile_backups=10
stderr_capture_maxbytes=1MB
stderr_events_enabled=false
environment=A="1",B="2"
serverurl=AUTO

[include] Section Settings

The supervisord.conf file may contain a section named [include]. If the configuration file contains an [include] section, it must contain a single key named “files”. The values in this key specify other configuration files to be included within the configuration.

Note

The [include] section is processed only by supervisord. It is ignored by supervisorctl.

[include] Section Values

files

A space-separated sequence of file globs. Each file glob may be absolute or relative. If the file glob is relative, it is considered relative to the location of the configuration file which includes it. A “glob” is a file pattern which matches a specified pattern according to the rules used by the Unix shell. No tilde expansion is done, but *, ?, and character ranges expressed with [] will be correctly matched. The string expression is evaluated against a dictionary that includes host_node_name and here (the directory of the supervisord config file). Recursive includes from included files are not supported.

Default: No default (required)

Required: Yes.

Introduced: 3.0

Changed: 3.3.0. Added support for the host_node_name expansion.

[include] Section Example

[include]
files = /an/absolute/filename.conf /an/absolute/*.conf foo.conf config??.conf

[group:x] Section Settings

It is often useful to group “homogeneous” process groups (aka “programs”) together into a “heterogeneous” process group so they can be controlled as a unit from Supervisor’s various controller interfaces.

To place programs into a group so you can treat them as a unit, define a [group:x] section in your configuration file. The group header value is a composite. It is the word “group”, followed directly by a colon, then the group name. A header value of [group:foo] describes a group with the name of “foo”. The name is used within client applications that control the processes that are created as a result of this configuration. It is an error to create a group section that does not have a name. The name must not include a colon character or a bracket character.

For a [group:x], there must be one or more [program:x] sections elsewhere in your configuration file, and the group must refer to them by name in the programs value.

If “homogeneous” process groups (represented by program sections) are placed into a “heterogeneous” group via [group:x] section’s programs line, the homogeneous groups that are implied by the program section will not exist at runtime in supervisor. Instead, all processes belonging to each of the homogeneous groups will be placed into the heterogeneous group. For example, given the following group configuration:

[group:foo]
programs=bar,baz
priority=999

Given the above, at supervisord startup, the bar and baz homogeneous groups will not exist, and the processes that would have been under them will now be moved into the foo group.

[group:x] Section Values

programs

A comma-separated list of program names. The programs which are listed become members of the group.

Default: No default (required)

Required: Yes.

Introduced: 3.0

priority

A priority number analogous to a [program:x] priority value assigned to the group.

Default: 999

Required: No.

Introduced: 3.0

[group:x] Section Example

[group:foo]
programs=bar,baz
priority=999

[fcgi-program:x] Section Settings

Supervisor can manage groups of FastCGI processes that all listen on the same socket. Until now, deployment flexibility for FastCGI was limited. To get full process management, you could use mod_fastcgi under Apache but then you were stuck with Apache’s inefficient concurrency model of one process or thread per connection. In addition to requiring more CPU and memory resources, the process/thread per connection model can be quickly saturated by a slow resource, preventing other resources from being served. In order to take advantage of newer event-driven web servers such as lighttpd or nginx which don’t include a built-in process manager, you had to use scripts like cgi-fcgi or spawn-fcgi. These can be used in conjunction with a process manager such as supervisord or daemontools but require each FastCGI child process to bind to its own socket. The disadvantages of this are: unnecessarily complicated web server configuration, ungraceful restarts, and reduced fault tolerance. With fewer sockets to configure, web server configurations are much smaller if groups of FastCGI processes can share sockets. Shared sockets allow for graceful restarts because the socket remains bound by the parent process while any of the child processes are being restarted. Finally, shared sockets are more fault tolerant because if a given process fails, other processes can continue to serve inbound connections.

With integrated FastCGI spawning support, Supervisor gives you the best of both worlds. You get full-featured process management with groups of FastCGI processes sharing sockets without being tied to a particular web server. It’s a clean separation of concerns, allowing the web server and the process manager to each do what they do best.

Note

The socket manager in Supervisor was originally developed to support FastCGI processes but it is not limited to FastCGI. Other protocols may be used as well with no special configuration. Any program that can access an open socket from a file descriptor (e.g. with socket.fromfd in Python) can use the socket manager. Supervisor will automatically create the socket, bind, and listen before forking the first child in a group. The socket will be passed to each child on file descriptor number 0 (zero). When the last child in the group exits, Supervisor will close the socket.

Note

Prior to Supervisor 3.4.0, FastCGI programs ([fcgi-program:x]) could not be referenced in groups ([group:x]).

All the options available to [program:x] sections are also respected by fcgi-program sections.

[fcgi-program:x] Section Values

[fcgi-program:x] sections have a few keys which [program:x] sections do not have.

socket

The FastCGI socket for this program, either TCP or UNIX domain socket. For TCP sockets, use this format: tcp://localhost:9002. For UNIX domain sockets, use unix:///absolute/path/to/file.sock. String expressions are evaluated against a dictionary containing the keys “program_name” and “here” (the directory of the supervisord config file).

Default: No default.

Required: Yes.

Introduced: 3.0

socket_backlog

Sets socket listen(2) backlog.

Default: socket.SOMAXCONN

Required: No.

Introduced: 3.4.0

socket_owner

For UNIX domain sockets, this parameter can be used to specify the user and group for the FastCGI socket. May be a UNIX username (e.g. chrism) or a UNIX username and group separated by a colon (e.g. chrism:wheel).

Default: Uses the user and group set for the fcgi-program

Required: No.

Introduced: 3.0

socket_mode

For UNIX domain sockets, this parameter can be used to specify the permission mode.

Default: 0700

Required: No.

Introduced: 3.0

Consult [program:x] Section Settings for other allowable keys, delta the above constraints and additions.

[fcgi-program:x] Section Example

[fcgi-program:fcgiprogramname]
command=/usr/bin/example.fcgi
socket=unix:///var/run/supervisor/%(program_name)s.sock
socket_owner=chrism
socket_mode=0700
process_name=%(program_name)s_%(process_num)02d
numprocs=5
directory=/tmp
umask=022
priority=999
autostart=true
autorestart=unexpected
startsecs=1
startretries=3
exitcodes=0
stopsignal=QUIT
stopasgroup=false
killasgroup=false
stopwaitsecs=10
user=chrism
redirect_stderr=true
stdout_logfile=/a/path
stdout_logfile_maxbytes=1MB
stdout_logfile_backups=10
stdout_events_enabled=false
stderr_logfile=/a/path
stderr_logfile_maxbytes=1MB
stderr_logfile_backups=10
stderr_events_enabled=false
environment=A="1",B="2"
serverurl=AUTO

[eventlistener:x] Section Settings

Supervisor allows specialized homogeneous process groups (“event listener pools”) to be defined within the configuration file. These pools contain processes that are meant to receive and respond to event notifications from supervisor’s event system. See Events for an explanation of how events work and how to implement programs that can be declared as event listeners.

Note that all the options available to [program:x] sections are respected by eventlistener sections except for stdout_capture_maxbytes. Eventlisteners cannot emit process communication events on stdout, but can emit on stderr (see Capture Mode).

[eventlistener:x] Section Values

[eventlistener:x] sections have a few keys which [program:x] sections do not have.

buffer_size

The event listener pool’s event queue buffer size. When a listener pool’s event buffer is overflowed (as can happen when an event listener pool cannot keep up with all of the events sent to it), the oldest event in the buffer is discarded.

events

A comma-separated list of event type names that this listener is “interested” in receiving notifications for (see Event Types for a list of valid event type names).

result_handler

A pkg_resources entry point string that resolves to a Python callable. The default value is supervisor.dispatchers:default_handler. Specifying an alternate result handler is a very uncommon thing to need to do, and as a result, how to create one is not documented.

Consult [program:x] Section Settings for other allowable keys, delta the above constraints and additions.

[eventlistener:x] Section Example

[eventlistener:theeventlistenername]
command=/bin/eventlistener
process_name=%(program_name)s_%(process_num)02d
numprocs=5
events=PROCESS_STATE
buffer_size=10
directory=/tmp
umask=022
priority=-1
autostart=true
autorestart=unexpected
startsecs=1
startretries=3
exitcodes=0
stopsignal=QUIT
stopwaitsecs=10
stopasgroup=false
killasgroup=false
user=chrism
redirect_stderr=false
stdout_logfile=/a/path
stdout_logfile_maxbytes=1MB
stdout_logfile_backups=10
stdout_events_enabled=false
stderr_logfile=/a/path
stderr_logfile_maxbytes=1MB
stderr_logfile_backups=10
stderr_events_enabled=false
environment=A="1",B="2"
serverurl=AUTO

[rpcinterface:x] Section Settings

Adding rpcinterface:x settings in the configuration file is only useful for people who wish to extend supervisor with additional custom behavior.

In the sample config file, there is a section which is named [rpcinterface:supervisor]. By default it looks like the following.

[rpcinterface:supervisor]
supervisor.rpcinterface_factory = supervisor.rpcinterface:make_main_rpcinterface

The [rpcinterface:supervisor] section must remain in the configuration for the standard setup of supervisor to work properly. If you don’t want supervisor to do anything it doesn’t already do out of the box, this is all you need to know about this type of section.

However, if you wish to add rpc interface namespaces in order to customize supervisor, you may add additional [rpcinterface:foo] sections, where “foo” represents the namespace of the interface (from the web root), and the value named by supervisor.rpcinterface_factory is a factory callable which should have a function signature that accepts a single positional argument supervisord and as many keyword arguments as required to perform configuration. Any extra key/value pairs defined within the [rpcinterface:x] section will be passed as keyword arguments to the factory.

Here’s an example of a factory function, created in the __init__.py file of the Python package my.package.

from my.package.rpcinterface import AnotherRPCInterface
def make_another_rpcinterface(supervisord, **config):
    retries = int(config.get('retries', 0))
    another_rpc_interface = AnotherRPCInterface(supervisord, retries)
    return another_rpc_interface

And a section in the config file meant to configure it.

[rpcinterface:another]
supervisor.rpcinterface_factory = my.package:make_another_rpcinterface
retries = 1

[rpcinterface:x] Section Values

supervisor.rpcinterface_factory

pkg_resources “entry point” dotted name to your RPC interface’s factory function.

Default: N/A

Required: No.

Introduced: 3.0

[rpcinterface:x] Section Example

[rpcinterface:another]
supervisor.rpcinterface_factory = my.package:make_another_rpcinterface
retries = 1