Subject: tape backups
To: None <netbsd-users@NetBSD.ORG>
From: Achyutram Bhamidipaty <ram@cs.arizona.edu>
List: netbsd-users
Date: 01/30/1995 14:18:03
This should be an easy question to answer. I recently added an 8mm
tape (exabyte (8200?) if it matters) drive to my system and I'm trying
to set up some kind of automatic backup system.

Normally this would be rather easy, all you have to do is write a dump
script and give that to cron. But on occasion I shutdown netbsd and
boot dos to play some games (the preferred solution would be to have a
way to play dos games under netbsd :-) I wont hold my breath for this
one though). This is where the trouble starts. When I reboot the
machine the tape drive rewinds the tape! So I need some way to deal
with this (plus there the is very annoying fact that when a tape is
in the tape drive the probe proccess is much slower).

So what I'm looking for is some way to set up the system to cope with
the fact that the tape rewinds on reboot. Does anyone have any ideas?

I was thinking that maybe I could store something on the tape that would
tell me how many files are one the current tape and then I could just
fsf past them. Or I could put this info in a file on the machine itself.

Basically what I am looking for is general ideas on how to cope with
the rewind on reboot thing. Or for that matter any clever ideas on how
to create a good backup strategy. What I'd like to do is use one tape
per week. I figure I can do a level 0 on sunday and do level 1's for
the rest of the week. If someone has a better idea, please let me
know.

Also if anyone has ideas on why the probe is so slow that would help
also. I noticed that there are entries in scsi/st.c for rogue tape
devices. What are these entries used for? The one for the exabyte
was commented out, why?

Thanks for any advice!

-Ram
ram@cs.arizona.edu