"Hey, it seems it's easy enough to make backups with some tar'ing, but how do you actually recover them if you actually have to reformat and reinstall?
Would you just do a fresh new install and them overwrite the newly created directories with your saved tars? Seems like it would be a pain to pick and choose what to save. "
I am a huge advocate of rescue CDs:
My usual method of restoring from my tar CD backups is to boot my rescue CD, mount my backup CD, copy the relevant tar file to a spare partition, unpack the tarball, and cp -pR the relevent portions to the proper place on my system. Then I delete the files on the spare partition.
"What if you recovered a tar file and it included whatever the problem was that made you reinstall."
You keep generations of backup. I have a daily cron job that backs up all changed files to a backup partition. I use cpbk to do the backups so that it can also prune the dead wood in the backup partition. This backup is not compressed and any portion can simply be copied to the relevant place in my live system, either running the live system or running the LifeBoat CD.
I have a weekly backup that is tar files on CD. I keep two generation of backup CDs so that I can restore from as far back as two weeks ago.
I keep two generations of LifeBoat CDs. That way I have a workable LifeBoat CD even if my current system has a fatal bug.
The amount of work for me to keep all this backup is:
Once a week I run the tar CD backup.
Whenever I make a major change to Linux I create a new LifeBoat CD.
Be prepared. Create a LifeBoat CD.