How to upgrade PHP version?

[jenjen8]

I am trying to use YUM to upgrade the PHP version in my VPS from 4.3.9 to 5.x. I use YUM to do so.

> yum update php

After a reboot, the PHP version is still the same.

I am not sure how the yum works and where yum gets its software updates from.

Must I update YUM first?
How can I update yum?
Is there other ways to update software like RPM? I am not sure about RPM as well.

I would like to understand YUM more so that I can update other software. The OS is CentOS 4.

[iwannano1]

yum will not upgrade CentOS php 4 to PHP 5. This is done to keep system integrity. You have 2 choice

#1 Remove PHP 4 and manually install php 5 (which may or may not work). You need to download php5 rpm from centos mirror

#2 Upgrade to CentOS 5 which comes with Apache 2.2 and PHP 5.1.