My customer is asking me to upgrade from php 5.1.x to 5.2.x as his site is requesting it to run vbullettin. I am running CENTOS 5.2. Can I just run a yum update for php or not? Will this create problems with ispconfig?
A yum update doesn't cause any problems with ISPConfig, however it doesn't install PHP 5.2 on your server. AFAIK, CentOS 5.x comes with PHP 5.1.6, and an update will only install a newer version of 5.1.6, not 5.2.
therefore I suppose I have to download directly php 5.2 from php's website... will that be ok? or will I mess up everything?