PHP 8.3.4 Released!

Configuration

FPM uses php.ini syntax for its configuration file - php-fpm.conf, and pool configuration files.

List of global php-fpm.conf directives

pid string

Path to PID file. Default value: none.

error_log string

Path to error log file. Default value: #INSTALL_PREFIX#/log/php-fpm.log. If it's set to "syslog", log is sent to syslogd instead of being written in a local file.

log_level string

Error log level. Possible values: alert, error, warning, notice, debug. Default value: notice.

log_limit int

Log limit for the logged lines which allows to log messages longer than 1024 characters without wrapping. Default value: 1024. Available as of PHP 7.3.0.

log_buffering bool

Experimental logging without extra buffering. Default value: yes. Available as of PHP 7.3.0.

syslog.facility string

used to specify what type of program is logging the message. Default value: daemon.

syslog.ident string

Prepended to every message. If you have multiple FPM instances running on the same server, you can change the default value which must suit common needs. Default value: php-fpm.

emergency_restart_threshold int

If this number of child processes exit with SIGSEGV or SIGBUS within the time interval set by emergency_restart_interval, then FPM will restart. A value of 0 means 'Off'. Default value: 0 (Off).

emergency_restart_interval mixed

Interval of time used by emergency_restart_interval to determine when a graceful restart will be initiated. This can be useful to work around accidental corruptions in an accelerator's shared memory. Available Units: s(econds), m(inutes), h(ours), or d(ays). Default Unit: seconds. Default value: 0 (Off).

process_control_timeout mixed

Time limit for child processes to wait for a reaction on signals from master. Available units: s(econds), m(inutes), h(ours), or d(ays) Default Unit: seconds. Default value: 0.

process.max int

The maximum number of processes FPM will fork. This has been design to control the global number of processes when using dynamic PM within a lot of pools. Use it with caution. Default value: 0.

process.priority int

Specify the nice(2) priority to apply to the master process (only if set). The value can vary from -19 (highest priority) to 20 (lower priority). Default value: not set.

daemonize bool

Send FPM to background. Set to 'no' to keep FPM in foreground for debugging. Default value: yes.

rlimit_files int

Set open file descriptor rlimit for the master process. Default value: system defined value.

rlimit_core int

Set max core size rlimit for the master process. Default value: 0.

events.mechanism string

Specify the event mechanism FPM will use. The following is available: select, pool, epoll, kqueue (*BSD), port (Solaris). Default value: not set (auto detection).

systemd_interval int

When FPM is build with systemd integration, specify the interval, in second, between health report notification to systemd. Set to 0 to disable. Default value: 10.

List of pool directives

With FPM you can run several pools of processes with different setting. These are settings that can be tweaked per pool.

listen string

The address on which to accept FastCGI requests. Valid syntaxes are: 'ip.add.re.ss:port', 'port', '/path/to/unix/socket'. This option is mandatory for each pool.

listen.backlog int

Set listen(2) backlog. A value of -1 means maximum on BSD systems. Default value: -1 (FreeBSD or OpenBSD) or 511 (Linux and other platforms).

listen.allowed_clients string

List of IPv4 or IPv6 addresses of FastCGI clients which are allowed to connect. Equivalent to the FCGI_WEB_SERVER_ADDRS environment variable in the original PHP FastCGI (5.2.2+). Makes sense only with a tcp listening socket. Each address must be separated by a comma. If this value is left blank, connections will be accepted from any ip address. Default value: not set (any ip address accepted).

listen.owner string

Set permissions for unix socket, if one is used. In Linux, read/write permissions must be set in order to allow connections from a web server. Many BSD-derived systems allow connections regardless of permissions. Default values: user and group are set as the running user, mode is set to 0660.

listen.group string

See listen.owner.

listen.mode string

See listen.owner.

listen.acl_users string

When POSIX Access Control Lists are supported you can set them using this option. When set, listen.owner and listen.group are ignored. Value is a comma separated list of user names.

listen.acl_groups string

See listen.acl_users. Value is a comma separated list of group names.

user string

Unix user of FPM processes. This option is mandatory.

group string

Unix group of FPM processes. If not set, the default user's group is used.

pm string

Choose how the process manager will control the number of child processes. Possible values: static, ondemand, dynamic. This option is mandatory.

static - the number of child processes is fixed (pm.max_children).

ondemand - the processes spawn on demand (when requested, as opposed to dynamic, where pm.start_servers are started when the service is started.

dynamic - the number of child processes is set dynamically based on the following directives: pm.max_children, pm.start_servers, pm.min_spare_servers, pm.max_spare_servers.

pm.max_children int

The number of child processes to be created when pm is set to static and the maximum number of child processes to be created when pm is set to dynamic. This option is mandatory.

This option sets the limit on the number of simultaneous requests that will be served. Equivalent to the ApacheMaxClients directive with mpm_prefork and to the PHP_FCGI_CHILDREN environment variable in the original PHP FastCGI.

pm.start_servers int

The number of child processes created on startup. Used only when pm is set to dynamic. Default Value: min_spare_servers + (max_spare_servers - min_spare_servers) / 2.

pm.min_spare_servers int

The desired minimum number of idle server processes. Used only when pm is set to dynamic. Also mandatory in this case.

pm.max_spare_servers int

The desired maximum number of idle server processes. Used only when pm is set to dynamic. Also mandatory in this case.

pm.max_spawn_rate int

The number of rate to spawn child processes at once. Used only when pm is set to dynamic. Default value: 32

pm.process_idle_timeout mixed

The number of seconds after which an idle process will be killed. Used only when pm is set to ondemand. Available units: s(econds)(default), m(inutes), h(ours), or d(ays). Default value: 10s.

pm.max_requests int

The number of requests each child process should execute before respawning. This can be useful to work around memory leaks in 3rd party libraries. For endless request processing specify '0'. Equivalent to PHP_FCGI_MAX_REQUESTS. Default value: 0.

pm.status_listen string

The address on which to accept FastCGI status request. This creates a new invisible pool that can handle requests independently. This is useful if the main pool is busy with long running requests because it is still possible to get the FPM status page before finishing the long running requests. The syntax is the same as for listen directive. Default value: none.

pm.status_path string

The URI to view the FPM status page. This value must start with a leading slash (/). If this value is not set, no URI will be recognized as a status page. Default value: none.

ping.path string

The ping URI to call the monitoring page of FPM. If this value is not set, no URI will be recognized as a ping page. This could be used to test from outside that FPM is alive and responding. Please note that the value must start with a leading slash (/).

ping.response string

This directive may be used to customize the response to a ping request. The response is formatted as text/plain with a 200 response code. Default value: pong.

process.priority int

Specify the nice(2) priority to apply to the worker process (only if set). The value can vary from -19 (highest priority) to 20 (lower priority). Default value: not set.

process.dumpable bool

Set the process dumpable flag (PR_SET_DUMPABLE prctl) even if the process user or group is different than the master process user. It allows to create process core dump and ptrace the process for the pool user. Default Value: no. Since PHP 7.0.29, 7.1.17 and 7.2.5.

prefix string

Specify prefix for path evaluation

request_terminate_timeout mixed

The timeout for serving a single request after which the worker process will be killed. This option should be used when the 'max_execution_time' ini option does not stop script execution for some reason. A value of '0' means 'Off'. Available units: s(econds)(default), m(inutes), h(ours), or d(ays). Default value: 0.

request_terminate_timeout_track_finished bool

The timeout set by request_terminate_timeout is not engaged after a fastcgi_finish_request or when application has finished and internal shutdown functions are being called. This directive will enable timeout limit to be applied unconditionally even in such cases. Default value: no. Since PHP 7.3.0.

request_slowlog_timeout mixed

The timeout for serving a single request after which a PHP backtrace will be dumped to the 'slowlog' file. A value of '0' means 'Off'. Available units: s(econds)(default), m(inutes), h(ours), or d(ays). Default value: 0.

request_slowlog_trace_depth int

The depth of slowlog log stack trace. Default value: 20. Since PHP 7.2.0.

slowlog string

The log file for slow requests. Default value: #INSTALL_PREFIX#/log/php-fpm.log.slow.

rlimit_files int

Set open file descriptor rlimit for child processes in this pool. Default value: system defined value.

rlimit_core int

Set max core size rlimit for child processes in this pool. Possible Values: 'unlimited' or an integer greater or equal to 0. Default value: system defined value.

chroot string

Chroot to this directory at the start. This value must be defined as an absolute path. When this value is not set, chroot is not used.

chdir string

Chdir to this directory at the start. This value must be an absolute path. Default value: current directory or / when chroot.

catch_workers_output bool

Redirect worker stdout and stderr into main error log. If not set, stdout and stderr will be redirected to /dev/null according to FastCGI specs. Default value: no.

decorate_workers_output bool

Enable the output decoration for workers output when catch_workers_output is enabled. Default value: yes. Available as of PHP 7.3.0.

clear_env bool

Clear environment in FPM workers. Prevents arbitrary environment variables from reaching FPM worker processes by clearing the environment in workers before env vars specified in this pool configuration are added. Default value: Yes.

security.limit_extensions string

Limits the extensions of the main script FPM will allow to parse. This can prevent configuration mistakes on the web server side. You should only limit FPM to .php extensions to prevent malicious users to use other extensions to execute php code. Default value: .php .phar

apparmor_hat string

If AppArmor is enabled, it allows to change a hat. Default value: not set

access.log string

The access log file. Default value: not set

access.format string

The access log format. Default value: "%R - %u %t \"%m %r\" %s":

Valid options
Placeholder Description
%C %CPU
%d duration µs
%e fastcgi env
%f script
%l content length
%m method
%M memory
%n pool name
%o header output
%p PID
%q query string
%Q the glue between %q and %r
%r request URI
%R remote IP address
%s status
%T time
%t time
%u remote user

It's possible to pass additional environment variables and update PHP settings of a certain pool. To do this, you need to add the following options to the pool configuration file.

Example #1 Passing environment variables and PHP settings to a pool

env[HOSTNAME] = $HOSTNAME
env[PATH] = /usr/local/bin:/usr/bin:/bin
env[TMP] = /tmp
env[TMPDIR] = /tmp
env[TEMP] = /tmp

php_admin_value[sendmail_path] = /usr/sbin/sendmail -t -i -f www@my.domain.com
php_flag[display_errors] = off
php_admin_value[error_log] = /var/log/fpm-php.www.log
php_admin_flag[log_errors] = on
php_admin_value[memory_limit] = 32M
PHP settings passed with php_value or php_flag will overwrite their previous value. Please note that defining disable_functions or disable_classes will not overwrite previously defined php.ini values, but will append the new value instead.

Settings defined with php_admin_value and php_admin_flag cannot be overridden with ini_set().

PHP settings can be set in the webserver configuration.

Example #2 set PHP settings in nginx.conf

set $php_value "pcre.backtrack_limit=424242";
set $php_value "$php_value \n pcre.recursion_limit=99999";
fastcgi_param  PHP_VALUE $php_value;

fastcgi_param  PHP_ADMIN_VALUE "open_basedir=/var/www/htdocs";
Caution

Because these settings are passed to php-fpm as fastcgi headers, php-fpm should not be bound to a worldwide accessible address. Otherwise, anyone could alter the PHP configuration options. See also listen.allowed_clients.

Note: Pools are not a security mechanism, because they do not provide full separation; e.g. all pools would use a single OPcache instance.

add a note

User Contributed Notes 13 notes

up
5
jon dot phpnetdonotspam at langevin dot me
1 year ago
PHP-FPM configuration page apparently doesn't see the need to specify what options are available with each version of PHP.

It claims that pm.status_listen is a valid directive, but that directive only exists as of php 8.0.0, which is a bummer for those of us still using PHP 7.4.

Noting this for anyone else fighting with this.
up
22
ikrabbe
6 years ago
It seems there is no way to get informed about the access log format codes that are used or can be used. All I found is the source code.

It would really help, not to have open questions when deploying php-fpm. I constantly struggle with file paths for example, but that is another topic.

case '%': /* '%' */
case 'C': /* %CPU */
case 'd': /* duration µs */
case 'e': /* fastcgi env */
case 'f': /* script */
case 'l': /* content length */
case 'm': /* method */
case 'M': /* memory */
case 'n': /* pool name */
case 'o': /* header output */
case 'p': /* PID */
case 'P': /* PID */
case 'q': /* query_string */
case 'Q': /* '?' */
case 'r': /* request URI */
case 'R': /* remote IP address */
case 's': /* status */
case 'T':
case 't': /* time */
case 'u': /* remote user */
up
12
rob at librobert dot net
2 years ago
The 'index' directive that is used in php-fpm.conf is not documented here. However, this directive can also be used in the pool configurations. In the included file, the $pool variable is substituted correctly.

This means that, if you have multiple pools with similar configurations, you can create a file 'default-values.inc' like so:

-----
listen.allowed_clients = 127.0.0.1

pm = dynamic
pm.max_children = X
pm.min_spare_servers = X
pm.max_spare_servers = X

access.log = /var/log/php-fpm/$pool.access
access.format = "%R %u [%t] \"%m %r\" %s %d %l"
slowlog = /var/log/php-fpm/$pool.slow

php_flag[short_open_tag] = off
-----

And then include that file in each pool configuration like so:

-----
[vhost1.example.com]
user = www-vhost1
group = www-vhost1

listen = 127.0.0.1:9001

include = /usr/local/etc/php-fpm.d/default-values.inc
-----

This makes things a bit more transparent, and it could potentially save some time if you decide to change settings.

Make sure the name of the included file does not end in '.conf', because all files with that extension are loaded from php-fpm.conf.
up
17
gadnet at aqueos dot com
9 years ago
the doc is lacking a lot of things it seems.

The php fpm exemple config file indicate different thing, more option etc... I wonder why the main documentation is less verbose that the configuration file that user can have .. or not have ?
up
4
rob at librobert dot net
2 years ago
Correction for my previous note...

I wrote "The 'index' directive that is used in php-fpm.conf".

But obviously I meant "The 'include' directive"...
up
10
Frank DENIS
12 years ago
The default value for listen.backlog isn't exactly "unlimited".

It's 128 on some operating systems, and -1 (which doesn't mean "unlimited" as well, but is an alias to a hard limit) on other systems.

Check for a sysctl value like kern.somaxconn (OpenBSD) or net.core.somaxconn (Linux).

Crank it up if you need more PHP workers than the default value. Then adjust listen.backlog in your php-fpm configuration file to the same value.

-Frank.
up
1
antonfedonyuk at gmail dot com
2 years ago
NOTE: "access.format" containing "%o" generate error in PHP 7.4 (don't tested in other versions)
up
6
frederic at juliana-multimedia dot com
5 years ago
With Apache, mod_proxy_fcgi and php-fpm, if you want to have a generic pool and several vhost with different php configuration, you can use the ProxyFCGISetEnvIf directive and the PHP_ADMIN_VALUE environment variable. It does not work with PHP_ADMIN_FLAG even for boolean directives.

PHP directives must be separated by spaces and a \n.

ProxyFCGISetEnvIf "true" PHP_ADMIN_VALUE "open_basedir=/var/www/toto/:/tmp/ \n session.save_path=/var/www/toto/session \n display_errors=On \n error_reporting=-1"
up
1
david dot cancalon at proxeem dot fr
3 years ago
Be very carrefull when using ProxyFCGISetEnvIf within a Apache virtual host configuration using a shared PHP-FPM pool. Values defined like this are shared across all the Apache virtual hosts within a pool worker, may resulting in strange behaviours depending on the requests chronology.

See full explanation here:
https://serverfault.com/questions/817020/stop-reusing-php-value-for-different-sites-with-php-fpm/817905#817905
up
0
antonfedonyuk at gmail dot com
2 years ago
; The access log format.
; The following syntax is allowed
; %%: the '%' character
; %C: %CPU used by the request
; it can accept the following format:
; - %{user}C for user CPU only
; - %{system}C for system CPU only
; - %{total}C for user + system CPU (default)
; %d: time taken to serve the request
; it can accept the following format:
; - %{seconds}d (default)
; - %{milliseconds}d
; - %{milli}d
; - %{microseconds}d
; - %{micro}d
; %e: an environment variable (same as $_ENV or $_SERVER)
; it must be associated with embraces to specify the name of the env
; variable. Some examples:
; - server specifics like: %{REQUEST_METHOD}e or %{SERVER_PROTOCOL}e
; - HTTP headers like: %{HTTP_HOST}e or %{HTTP_USER_AGENT}e
; %f: script filename
; %l: content-length of the request (for POST request only)
; %m: request method
; %M: peak of memory allocated by PHP
; it can accept the following format:
; - %{bytes}M (default)
; - %{kilobytes}M
; - %{kilo}M
; - %{megabytes}M
; - %{mega}M
; %n: pool name
; %o: output header
; it must be associated with embraces to specify the name of the header:
; - %{Content-Type}o
; - %{X-Powered-By}o
; - %{Transfert-Encoding}o
; - ....
; %p: PID of the child that serviced the request
; %P: PID of the parent of the child that serviced the request
; %q: the query string
; %Q: the '?' character if query string exists
; %r: the request URI (without the query string, see %q and %Q)
; %R: remote IP address
; %s: status (response code)
; %t: server time the request was received
; it can accept a strftime(3) format:
; %d/%b/%Y:%H:%M:%S %z (default)
; The strftime(3) format must be encapsulated in a %{<strftime_format>}t tag
; e.g. for a ISO8601 formatted timestring, use: %{%Y-%m-%dT%H:%M:%S%z}t
; %T: time the log has been written (the request has finished)
; it can accept a strftime(3) format:
; %d/%b/%Y:%H:%M:%S %z (default)
; The strftime(3) format must be encapsulated in a %{<strftime_format>}t tag
; e.g. for a ISO8601 formatted timestring, use: %{%Y-%m-%dT%H:%M:%S%z}t
; %u: remote user
;
; Default: "%R - %u %t \"%m %r\" %s"
access.format = "%R - %u %t \"%m %r%Q%q\" %s %f %{milli}d %{kilo}M %C%%"

https://github.com/php/php-src/blob/master/sapi/fpm/www.conf.in#L257-L318
up
-4
Yousef Ismaeil Cliprz
10 years ago
Check if fastCGI enabled

<?php
// You can use isset or is_null for $_SERVER['FCGI_SERVER_VERSION']
function isFastCGI () {
return !
is_null($_SERVER['FCGI_SERVER_VERSION']);
}

?>
up
-8
sroussey at gmail dot com
11 years ago
Starting in 5.3.9 the security.limit_extensions configuration item has been added and it defaults to .php. If you need to execute other extensions, you have to change this setting.
up
-18
mb
8 years ago
If you need to disable security.limit_extensions variable, simply set the variable to FALSE like so:

security.limit_extensions = FALSE
To Top