🚀 go-pugleaf

In article <1992May19.020223.16714@decuac.dec.com>,
mjr@hussar.dco.dec.com (Marcus J. "will do TCP/IP for food" Ranum) writes:
...
|> 	*ahem* anyhow - I've noticed that tools like NSR or Networker
|> should cause users to shift their backup paradigms.
...
|> 	On my machines I have been doing nothing but incrementals
|> for over a year and a half. I haven't ever recycled a tape. I now
|> have 16 of them. 
...
|>           Typically if I need to recover something, the odds
|> are high that it's on the tape already in the drive.
...
|> 	Comments?
|> 
|> mjr.

Well, it all depends on why you are taking backups.  Your arguments seem
very sound, provided you assume that:

- The main reason you take backups is to recover from human error.
- Discs occasionally fail.
- All your tapes are perfectly safe.

However, people also take backups to protect against disasters such as
fire. It's no good having all your recent backups "in the drive" if
you lose the whole machine in some catastrophe.

Also tapes sometimes do go bad. The higher the recording density,
the more you stand to lose if one does.

The existence of devices such as the Exabyte and DAT certainly has
changed my outlook on backups.  I can afford to take complete dumps
more often and keep more of them.  Backup "requirements" have increased
enormously, simply because it is now possible to do more!

Of course, it would be nice to have all the backups indexed AS WELL,
I don't deny that.

Martyn Johnson      maj@cl.cam.ac.uk
University of Cambridge Computer Lab
Cambridge UK