How can I restore my Debian system with a tar-backup of the whole "/"-folder (all files und folders)?
Must I create an ISO or what?
If someone gave me a tar archive of a completely failed system and asked me to restore it I would probably do things about like this.
/etc/fstab
from the tar to get an idea of the correct filesystem setup/target
/target
)/etc/fstab
, and other related files that may be referencing filesystems by UUID. It all depends on if LVM, RAID, FDE, or something else was in use.This is far from the only way though. I could probably come up with a dozen different ways that may be better or worse depending on the specific circumstances.
Sounds like you need to boot into a recovery disk, or Debian live CD (https://www.debian.org/CD/http-ftp/#stable), etc. and then restore, but are you certain something less drastic cant be done?
Not sure what you are fixing.
It depends.
If you are already booted into the system and need to untar the root filesystem. First create a directory that isn't included in the original filesystem. Move the tarball to that directory and just extract it.
If your filesystem is toast, then you'll need to boot into a live CD, mount the hard drive (/dev/sdb or whatever it might be), and then extract the tarball to that mounted location.
If any of the system changed, like grub or drivers, then things get a little bit more complicated. Additional information will help us tremendously in helping you out.
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