Re: ext3 and undeletion

Andreas Dilger
2002-02-26T18:17:12Z

On Feb 26, 2002 10:00 -0800, H. Peter Anvin wrote:
> Rose, Billy wrote:
> > My company can tolerate 0% loss of data (which is why I raised this issue).
>
> There is no such thing as 0% loss of data. You can get some amount of
> security with backups, snapshots (really useful!) or undelete, but you
> can *NEVER* guarantee 0% loss of data... consider the case when a
> (l)user overwrites (not just deletes) a newly created file.

Snapshots at the filesystem level could handle the overwrite case.

However, even then it cannot be 0% loss of data, unless you have snapshots
for _every_ write of the file, which would quickly become prohibitive in
space usage (think autobackup from an editor on a large file). Sometimes
people just have to learn from their mistakes...

Cheers, Andreas
--
Andreas Dilger