Upgrade PHP on live server.

[shaggycap]

I am about to upgrade the version of PHP on a server and need some good advice.

The company linux server hosts websites for about 60 clients, and I need to make the right choice so I don't break anything.

The version at the moment is 4.1.2 (OLD!!) and the link to the phpinfo is:

http://www.cms.istl.com/phpinfo.php

But this is too old for the new framework I am using (codeigniter) as this requires a minimum of 4.3 to run.

I am trying to decide on which version is best to upgrade to, ideally it would be v5.2, which is the very latest official release, but I am thinking that could potentially cause problems with old code? I have no idea exactly what php code is on the server, but I do know that there is a complex invoice application running.

Would it be safe to upgrade to v4.4.4, which is the latest of the 'fours', or would it be wise to make the jump to the 'fives'?

I hold my breath and await your words of wisdom :)

Chris.

[wildteen88]

You can upgrade to any version you wish. PHP4 code will still run on PHP5

However the thing that will cause sites to malfunction will be PHPs configuration. If you do upgrade, create a backup copy of the existing php.ini and then when you upgrade PHP reconfigure PHP to what the old version of PHPs configuration was.

I see in your PHP ini you have a few settings which are turned off by default as of PHP4.3, namely register_globals and magic_quotes_gpc. If you keep register globals disabled then there will be a strong chance of websites malfunctioning.
Register_globals can be a security problem and was one of the reason why it was disabled. However I would still enable the setting and then perhaps get existing customers to upgrade there sites so they dont reply on this setting.