FPM uses php.ini syntax for its configuration file - php-fpm.conf, and pool configuration files.
pid
stringPath 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
stringError log level. Possible values: alert, error, warning, notice, debug. Default value: notice.
log_limit
intLog 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
boolExperimental logging without extra buffering. Default value: yes. Available as of PHP 7.3.0.
syslog.facility
stringused to specify what type of program is logging the message. Default value: daemon.
syslog.ident
stringPrepended 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
mixedTime 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
intThe 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
intSpecify 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
boolSend FPM to background. Set to 'no' to keep FPM in foreground for debugging. Default value: yes.
rlimit_files
intSet open file descriptor rlimit for the master process. Default value: system defined value.
rlimit_core
intSet max core size rlimit for the master process. Default value: 0.
events.mechanism
stringSpecify 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
intWhen 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.
With FPM you can run several pools of processes with different setting. These are settings that can be tweaked per pool.
listen
stringThe 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
stringList 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
stringSet 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
stringUnix user of FPM processes. This option is mandatory.
group
stringUnix 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
intThe 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
stringThe 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
stringThe 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
stringThe 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
stringThis 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
intSpecify 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
boolSet 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
stringSpecify prefix for path evaluation
request_terminate_timeout
mixedThe 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
boolThe 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
mixedThe 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
intThe 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
intSet open file descriptor rlimit for child processes in this pool. Default value: system defined value.
rlimit_core
intSet 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
stringChroot 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
stringChdir to this directory at the start. This value must be an absolute path. Default value: current directory or / when chroot.
catch_workers_output
boolRedirect 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
boolEnable the output decoration for workers output when catch_workers_output is enabled. Default value: yes. Available as of PHP 7.3.0.
clear_env
boolClear 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
stringLimits 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
stringIf AppArmor is enabled, it allows to change a hat. Default value: not set
access.log
stringThe access log file. Default value: not set
access.format
string The access log format. Default value: "%R - %u %t \"%m %r\" %s"
:
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_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";
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.