Server currently running CentOS 5.2. Developers tell me they'd like the machine upgrade to CentOS 5.3 -- but not all the way to CentOS 5.4, as they haven't tested with 5.4 yet.
I'm pretty sure a yum upgrade will put me at 5.4, as a yum check-update shows all sorts of 5.4 packages.
So how do I move up to 5.3?
work around for such scenario you can download centos 5.3 dvd, and create local repo ans then you run the yum upgrade
If you're going to run into this problem repeatedly and you want better long-term control over rolling packages out over multiple environments (development, staging, production), you should look into setting yourself up a [Spacewalk][1] server, and then you'll be able to create frozen-in-time channels that correspond to particular releases that you can attach/upgrade servers to.
[1]: http://www.redhat.com/spacewalk/ Spacewalk
Just point it directly at the dvd to upgrade. http://www.cyberciti.biz/faq/centos-linux-install-packages-from-dvd-using-yum/