Exploring best approach to upgrading RHEL from version 5.7 to 6.x
 

I am relatively new to RHEL coming from the Unix world and have inherited a version 5.7 installation of RHEL. The platform is Intel x86_64. My application vendor requires that I upgrade to version 6 and I understand that it is better to do a fresh install over the V5.7 after backup. It's possible that I could hire a consultant for the upgrade/knowledge transfer. Is this a common practice and/or a good approach. We have a pretty tight deadline coming up and I need to get our Developers going on the new version. Please let me know if more information is necessary. Any input is greatly appreciated. Thanks.

As long as you don't have a lot of existing programs and configurations that you need to save (which will take a significant amount of time to set up again), it will always be cleanest to wipe and install the new version fresh.

I would just grab a backup drive, and if it's larger than the RHEL drive do a dd dump to back up everything, otherwise just copy over the files you want to back up. Then wipe your RHEL drive, install 6, and copy the necessary files back over.

Just extending on suicidaleggroll, you prob don't want to copy back cfg files, as they may have changed; you'll need to eyeball them carefully.
Certainly RH do not support in-place upgrades across major versiions

http://docs.redhat.com/docs/en-US/Re...grade-x86.html

Knowing which files to copy back to the fresh install of v6.x is the trick, I suppose. This is where, given the time constraint and having never done an upgrade, I am looking for a contractor to assist.