Just for once (again?), I'm gonna deal with linux / Unix system administration., and in particular, migration.
This may be related to scurity, as you may say that integrity does concern system configuration, when it's about renewing a server or transfering a whole system configuration from a machine to another.
First of all, let's say that you have an old server, and you want to migrate it to a new one, with new hardware. If you create an image of the whole system and restores it on the new server, it may just not work because of hardware differences and/or special configuration elements.
To insure a transfert with integroty check, I'll suggest you to use RSync. Here is what could the command line look like:
rsync -avchz --bwlimit=150 --stats /etc remote_host:/sync_etc
The way of synchronizing is source - > destination (last argument).
The bwlimit limits the bandwidth, so that you would not pay extra money for this (huge) transfer, depending on your hosting contract.
The folders that you would at least need to synchronize between the two servers are:
Special thanks: Roro, Duckx, Fredy, and Lucky ;) the guys who helped me meeting Linux ;)