Article in Hosting & Security

If you’re a windows host, or even used a windows server host, then I’m sure you’ve have to make a decision regarding PHP. Yes it’s true that most PHP users are usually using a Linux based distro, but as web technologies advance, it’s becoming more and more common for Windows host to install and utilize a cross breed of technologies such as ASP.NET, Python, PERL, and PHP. So instead of just utilizing Access Databases, and ASP, you can build a site utilizing asp for part of your site, and cross technology php for another portion.

Some of the previous argument about using PHP on IIS previously, where issue’s of stability and or speed on IIS. With the advent of IIS 5 and 6 and greater scripting technologies, most of these issue’s have been completely worked out, making PHP on IIS a viable option. PHP can be installed on a windows server a couple of different ways.

PHP supports two different types of interfaces. CGI and ISAPI, both of these can be used on IIS. Most people will tell you that using PHP in CGI Mode is better than the ISAPI mode load, but I have found ISAPI to run very stable on heavy traffic sites that I manage, most times it is always better than the CGI binary, unless you are running IIS 4 which does not do very well running the ISAPI version of PHP.

So for ease of use the CGI version may be the better option, but for stability I personally recommend the ISAPI version. There are actually even issues with some applications running PHP on IIS in CGI mode. Some of the common issue’s you may run into are CGI Timeouts, which can be adjusted by extending the amount of time you can take to execute CGI scripts.  Another difference in the CGI and ISAPI modes are, ISAPI is compiled and hooked into the server at load time, therefore it tends to be faster, and more robust, while PHP in CGI mode needs to be loaded then unloaded every time a call is made for it. In my opinion PHP in CGI mode should be more of a last resort option, especially if you’re using a strong Information Server such as version 5 or 6.

A few tips when setting up your server to run PHP in ISAPI mode.

Don’t use the php installer from the php.net site. It’s easy to use yes, but it will most certainly install php in CGI mode, utilizing the php.exe file and not the phpisapi.dll file.

Download the latest stable version of PHP and the PECL extensions. Extract the contents of the PHP zip into any directory of your choosing. (I prefer c:\php) Extract the contents of the PECL extensions into the ext directory you just created for PHP.

There are a few great articles on getting your php installed and running correctly, one I’d highly recommend would be http://www.peterguy.com/php/install_IIS6.html.

I hope this is helpful, and helps you in your decision on using PHP on IIS