Comment Re:Just ... why? (Score 3, Informative) 65
Let's see:
Hmm. All of them. They require the user to have more than two brain cells to rub together to spark a thought, but there are tons of options. Some are integrated to Desktops / Package Managers and can be turned on to do automatic work too.
1: BTRFS / ZFS snapshots.
2: DD images
3: Simple tarballs
4: Haven't found a non-embedded Linux yet that doesn't support disk / partition cloning software, especially sparse file disk cloning so you clone only the actual data.
5: Did I mention FS snapshots yet? They are made specifically for this. And some are Enterprise Ready level of support.
6: Some package managers can be set up to be able to revert changes to pre update / install states too.
Any / all of these ways can be used with ANY age. Haven't changed much on that ZFS cold storage volume that you just fat fingered changing the permissions on? Who the fuck cares if the snapshot is 180 days old? Take a new snapshot, restore the old snapshot, and compare file differences sorted by something other than the fucked up perms... It's not rocket surgery.
Or store a snapshot just before you do any major changes like perms. Then it's an easy rollback to 5 mins ago. But you still have the option to use the 180 day old snapshot too.