[comp.sys.sgi] Network backup suggestions?

ktl@wag240.caltech.edu (Kian-Tat Lim) (12/28/89)

	We have a 95% full 500 megabyte filesystem on our 4D/240 that
we would (very much) like to backup regularly.  The Iris only has a
cartridge tape drive, but another of our machines (running a fairly
standard 4.3 BSD) has a 6250 bpi 9 track.  The two machines are
connected by a lightly-loaded Ethernet.

1)	The filesystem is NFS mounted on the BSD machine.  We would
thus be able to use dump if we enabled root access to the remote
filesystem.  Are there any additional security holes we would
introduce by doing this?

2)	Is there a version of rdump available for the Iris (running
3.1F until application software catches up with the new release)?

3)	Is there any way to make bru to a pipe work properly over
multiple tapes?  It seems that if we specify an appropriate tape
size that bru will correctly split the archive, but the remote side of
the pipe will have difficulty discovering this and cannot communicate
end-of-tape messages back to bru to facilitate idiot-proofing.

4)	Any other suggestions?

--
Kian-Tat Lim (ktl@wagvax.caltech.edu, KTL @ CITCHEM.BITNET, GEnie: K.LIM1)

jmb@patton.SGI.COM (Jim Barton) (12/28/89)

In article <13089@cit-vax.Caltech.Edu>, ktl@wag240.caltech.edu (Kian-Tat
Lim) writes:
> 
> 	We have a 95% full 500 megabyte filesystem on our 4D/240 that
> we would (very much) like to backup regularly.  The Iris only has a
> cartridge tape drive, but another of our machines (running a fairly
> standard 4.3 BSD) has a 6250 bpi 9 track.  The two machines are
> connected by a lightly-loaded Ethernet.
> 
> 1)	The filesystem is NFS mounted on the BSD machine.  We would
> thus be able to use dump if we enabled root access to the remote
> filesystem.  Are there any additional security holes we would
> introduce by doing this?

The BSD 'dump' command actually understands the filesystem as laid out on
the disk.  I doubt that it can back up an NFS filesystem.  You probably need
to use tar if you're going to use this method.  Beware, though - NFS is
slow, expecially compared to a decent 9-track drive.

> 
> 2)	Is there a version of rdump available for the Iris (running
> 3.1F until application software catches up with the new release)?

No, there isn't.  This is mostly because 'dump' would have to be re-written
from scratch to work on the EFS filesystem rather than Berkeley's, and we
don't have extra grad students hanging around to do odd jobs like that.
Maybe someday ...

> 
> 3)	Is there any way to make bru to a pipe work properly over
> multiple tapes?  It seems that if we specify an appropriate tape
> size that bru will correctly split the archive, but the remote side of
> the pipe will have difficulty discovering this and cannot communicate
> end-of-tape messages back to bru to facilitate idiot-proofing.

BRU should support the BSD remote tape protocol.  If you specify the
remote tape device as <machine>:/dev/mt..., then it will use the /etc/rmt
daemon to do the dirty work.

> 
> 4)	Any other suggestions?

Tar over NFS seems your best bet if 'bru' doesn't work.

> 
> --
> Kian-Tat Lim (ktl@wagvax.caltech.edu, KTL @ CITCHEM.BITNET, GEnie: K.LIM1)


-- Jim Barton
   Silicon Graphics Computer Systems
   jmb@sgi.com