[CentOS] Linux backup help

Hi All;

I'm awaiting a new linux laptop that will be my primary work machine. I want 
to implement a strategy that allows me as easily as possible to revert back 
to a former state. My primary concern is a scenario where I apply system 
updates and it breaks something that for me is critical.   

I wonder if a simple rsync script would work. If so, here's what I'm thinking:

1) updates are available so I execute the rsync script which pulls any updated 
files from my laptop to a backup server/drive

2) apply updates

3) if something breaks (even if I can no longer login) I boot the laptop, run 
the rsync script in the opposite direction (push files from the backup drive 
to the laptop) 

I assume that if I were to execute step 3 above that my system would be in the 
exact state that it was before I ran the updates. Is this a correct 
assumption ?  Are there better approaches ?


Thanks in advance..