I used to set the append-only extended file attribute on important files
No one can delete the files afterwards, not even root, without removing the attribute first
It worked well with Mercurial, which is also append only. So I could commit as usually to my Mercurial repository, but it could not be deleted.
Ironically, I stopped doing that, because it messed my backups up. When running the backups as root, some tools would add the flag to the backuped files, but then later backups as non-root could not replace the file with new versions.
No one can delete the files afterwards, not even root, without removing the attribute first
It worked well with Mercurial, which is also append only. So I could commit as usually to my Mercurial repository, but it could not be deleted.
Ironically, I stopped doing that, because it messed my backups up. When running the backups as root, some tools would add the flag to the backuped files, but then later backups as non-root could not replace the file with new versions.