[Beowulf] Re: OT: LTO Ultrium (3) throughput?

[John Hearns]

On Fri, 2008-07-04 at 09:10 +0200, Geoff Galitz wrote:
> Backing up to tape allows you to go back to a specific point in
> history.  Particularly useful if you need to recover a file that has
> become corrupted or you need to rollback to a specific stage and you
> are unaware of that fact for a few days.

dirvish allows you to do exactly this on a RAID based backup system:

http://www.dirvish.org/
Dirvish has the concept of a "vault" which is defined to have a cerain
lifetime (weeks, months, years...) You make backup copies to your vault
- the smart thing being that any files which are unchanged since the
last backup are links to the first copy of the file. So your vault size
does not grow and grow endlessly. You can roll back to any given date.