Running mod_php and FastCGI side-by-side

me@mwop.net (Matthew Weier O'Phinney) — Sun, 15 Aug 2010 13:40:29 +0000

Because we're in full throes of Zend Framework 2.0 development, I find myself with a variety of PHP binaries floating around my system from both the PHP 5.2 and 5.3 release series. We're at a point now where I'm wanting to test migrating applications from ZF 1.X to 2.0 to se see what works and what doesn't. But that means I need more than one PHP binary enabled on my server...

I use Zend Server on my development box; it's easy to install, and uses my native Ubuntu update manager to get updates. On Ubuntu, it installs the Debian Apache2 packages, so I get the added bonus of familiarity with the configuration structure.

I installed Zend Server some time ago, so I'm still on a PHP 5.2 mod_php binary. I have several PHP 5.3 binaries compiled and installed locally for running unit tests and sample scripts already -- so the question was how to keep my 5.2 mod_php running while simultaneously allowing the ability to run selected vhosts in 5.3?

The answer can be summed up in one acronym: FastCGI.

With a little help from Ralph Schindler, I got things setup.

Enabling FastCGI on Ubuntu's Apache

Interestingly, FastCGI is not enabled by default, nor is another module you'll need, mod_actions. You can enable these very easily though:


% cd /etc/apache2/mods-enabled
% sudo ln -s ../mods-available/fastcgi.load .
% sudo ln -s ../mods-available/fastcgi.conf .
% sudo ln -s ../mods-available/actions.load .
% sudo ln -s ../mods-available/actions.conf .

Create a FastCGI-enabled vhost

Next, you need to add a new vhost that will utilize FastCGI. I copied an existing vhost I had in my /etc/apache2/sites-enabled tree, modified it to give it a unique ServerName and DocumentRoot, and added the following lines:


ScriptAlias /cgi-bin/ /path/to/zfproject/public/cgi-bin/
AddHandler php-fcgi .php
Action php-fcgi /cgi-bin/php-5.3.1

The name of the PHP script doesn't matter much; I used "php-5.3.1" so that I could visually recognize what version of PHP I was using with that vhost.

Create a "cgi-bin" directory and CGI script

Finally, I needed to actually create the "cgi-bin" directory and CGI script to execute. This was relatively simple; I navigated to my project's DocumentRoot, and created a new directory "cgi-bin" (mkdir cgi-bin).

I then entered that directory and created a new script, based on the name I provided in my vhost. That script, "cgi-bin/php-5.3.1" then simply exec's the php-cgi binary from my PHP install.

Note about CGI binaries

In PHP 5.3 and up, CGI binaries are built by default -- and they're already FastCGI enabled. In PHP 5.2, CGI versions are still built by default, but they are not FastCGI-enabled unless you explicitly pass the "--enable-fastcgi" configure flag. To determine if you did that when compiling, execute the following:


php-cgi -i | grep fcgi

If you get no output, you need to recompile.

My script looks like this:


#!/bin/bash
exec /path/to/php/install/bin/php-cgi \"$@\"

Because this is a CGI binary, you can pass additional CLI arguments and environment variables; try experimenting with setting your include_path, application environment, etc.

Once you're done creating the script, make sure it's executable:


chmod a+x php-5.3.1

Fire it up!

Once I'd done the above, I restarted my Apache instance (sudo /etc/init.d/apache2 restart). After ensuring there were no startup errors, I navigated to my new vhost, and voila! it was running.