CentOS 6 Apache 2.4 with PHP-FPM

PHP-FPM does have some advantages depending on the solution and the common path is to use Nginx with PHP-FPM. However what happens when you want to utilize the normal features of Apache, such as basics like .htaccess files, but still keep the tuning options open that come with PHP-FPM? Well, there is a module for that!

This guide is going to assume a fresh CentOS 6 server to illustrate everything from start to finish, and will assume that all sites on this server will use the same php-fpm pool.

Apache 2.2 has no native modules for working with fastcgi. So the options would be to install mod_fastcgi from source or use a older SRPM from repos that may not be too well known or maintained. As both those options are less than ideal, we will be installing Apache 2.4 from the IUS repository to avoid the patch management issues associated with source installations.

First, install the repos needed for the updated packages:

[[email protected] ~]# rpm -ivh http://dl.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm
[[email protected] ~]# rpm -ivh https://dl.iuscommunity.org/pub/ius/stable/CentOS/6/x86_64/ius-release-1.0-15.ius.centos6.noarch.rpm

Then install the required packages for your web server:

[[email protected] ~]# yum install httpd24u php56u-fpm

Now update the Apache configuration to use the mpm_event_module instead of the mpm_prefork_module:

[[email protected] ~]# vim /etc/httpd/conf.modules.d/00-mpm.conf 
# LoadModule mpm_prefork_module modules/mod_mpm_prefork.so
LoadModule mpm_worker_module modules/mod_mpm_worker.so

Then tell Apache to send all PHP requests over to PHP-FPM by creating a new configuration file:

[[email protected] ~]# vim /etc/httpd/conf.d/php.conf

# Tell the PHP interpreter to handle files with a .php extension.

<Proxy "unix:/var/run/php-fpm/default.sock|fcgi://php-fpm">
	# we must declare a parameter in here (doesn't matter which) or it'll not register the proxy ahead of time
	# Note: If you configure php-fpm to use the "ondemand" process manager, then use "ProxySet disablereuse=on"
	ProxySet disablereuse=off
</Proxy>

# Redirect to the proxy
<FilesMatch \.php$>
	SetHandler proxy:fcgi://php-fpm
</FilesMatch>

Tweak PHP-FPM to use sockets instead of TCP connections for performance purposes as follows:

[[email protected] ~]# vim /etc/php-fpm.d/www.conf
; listen = 127.0.0.1:9000
listen = /var/run/php-fpm/default.sock
...
listen.owner = apache
listen.group = apache
listen.mode = 0660
user = apache
group = apache

Enable the services to start on boot and start them up:

[[email protected] ~]# chkconfig php-fpm on
[[email protected] ~]# chkconfig httpd on
[[email protected] ~]# service php-fpm start
[[email protected] ~]# service httpd start

If you are using a software firewall on the server, open ports 80/443 accordingly. This example will open them up to the world. Adjust yours accordingly:

[[email protected] ~]# vim /etc/sysconfig/iptables
-A INPUT -p tcp -m tcp --dport 443 -j ACCEPT 
-A INPUT -p tcp -m tcp --dport 80 -j ACCEPT 
[[email protected] ~]# service iptables restart

Finally, test a site to ensure PHP is working and is using PHP-FPM by creating the file below, then visiting the page at x.x.x.x/info.php:

[[email protected] ~]# vim /var/www/html/info.php
<?php phpinfo(); ?>

And your done!

Using multiple PHP-FPM pools

What happens if you want to isolate each site to their own PHP-FPM pool instead of using a shared pool? That is easy enough to do. Assuming that you followed everything in this guide to get to this point, do the following.

First, disable the global Apache configuration for PHP:

[[email protected] ~]# mv /etc/httpd/conf.d/php.conf /etc/httpd/conf.d/php.conf.bak

Create a new PHP-FPM pool for this specific site and update it accordingly:

[[email protected] ~]# cp /etc/php-fpm.d/www.conf /etc/php-fpm.d/example.com.conf
[[email protected] ~]# vim /etc/php-fpm.d/example.com.conf
; Start a new pool named 'www'.
; the variable $pool can we used in any directive and will be replaced by the
; pool name ('www' here)
[example.com]
...
; listen = 127.0.0.1:9000
listen = /var/run/php-fpm/example.com.sock
...
listen.owner = apache
listen.group = apache
listen.mode = 0660
user = apache
group = apache

Then update the site’s Apache vhost to point to a new PHP-FPM pool in both the 80 and 443 stanzas. Be sure to update the socket accordingly for your site in the 2 sections below! (ie: unix:/var/run/php-fpm/example.com.sock)

[[email protected] ~]# vim /etc/httpd/vhost.d/example.com.conf
<VirtualHost *:80>
        ServerName example.com
        ServerAlias www.example.com
        DocumentRoot /var/www/vhosts/example.com

	# Send PHP requests to php-fpm
	<Proxy "unix:/var/run/php-fpm/example.com.sock|fcgi://php-fpm">
		# we must declare a parameter in here (doesn't matter which) or it'll not register the proxy ahead of time
		# Note: If you configure php-fpm to use the "ondemand" process manager, then use "ProxySet disablereuse=on"
		ProxySet disablereuse=off
	</Proxy>

	# Redirect to the proxy
	<FilesMatch \.php$>
		SetHandler proxy:fcgi://php-fpm
	</FilesMatch>
...
<VirtualHost *:443>
        ServerName example.com
        ServerAlias www.example.com
        DocumentRoot /var/www/vhosts/example.com

	# Send PHP requests to php-fpm
	<Proxy "unix:/var/run/php-fpm/example.com.sock|fcgi://php-fpm">
		# we must declare a parameter in here (doesn't matter which) or it'll not register the proxy ahead of time
		# Note: If you configure php-fpm to use the "ondemand" process manager, then use "ProxySet disablereuse=on"
		ProxySet disablereuse=off
	</Proxy>

	# Redirect to the proxy
	<FilesMatch \.php$>
		SetHandler proxy:fcgi://php-fpm
	</FilesMatch>
...

Then restart the services:

[[email protected] ~]# service php-fpm restart
[[email protected] ~]# service httpd restart

Finally, test a site to ensure PHP is working and is using PHP-FPM by creating the file below, then visiting the page at example.com/info.php:

[[email protected] ~]# vim /var/www/vhosts/example.com/info.php
<?php phpinfo(); ?>

And your done!