[clue-tech] Upgrading Linux in-place

[Todd A. Gibson]

Hello,
My production box is running Red Hat 7.2.  All these years I've
survived through upgrading individual tools (e.g., PHP, glibc, MySQL,
etc.) The pain now is nearly unbearable.  I'm hitting walls with my
outdated kernel. I must upgrade soon.

I am running Arch Linux on my development box so I'm inclined to go
with that distribution on my production box, though I would entertain
using a different distribution if there is a compelling reason.

A couple observations:
1) I want to upgrade the box in-place, so I imagine chroot would
be used in some capacity.
2) I'm running both Web and mail services.  I envision an iterative
trial and error process to get all of the correct software installed
and configured.  That is, a regular scenario I anticipate is booting
into the new system, identifying problems that need resolving, and
then rebooting into the old system to get the server online again
while I resolve issues.

Is it feasible for me to do this in-place?  Can anyone offer tips,
tricks, or a broad roadmap I can follow to accomplish this?  I'm
technically savvy with Linux, but my entire OS install
experience has been limited to boxes which I was able to wipe
clean and start from scratch.

Thanks,
-TAG
Todd A. Gibson