Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!uw-beaver!rice!sun-spots-request
From: wor-mein!dave@uunet.uu.net (Dave Axness)
Newsgroups: comp.sys.sun
Subject: Re: Exabyte 8mm Video Tape Drive Review?
Message-ID: <8902142214.AA28410@wor-mein.UUCP>
Date: 23 Feb 89 04:19:17 GMT
Sender: usenet@rice.edu
Organization: Sun-Spots
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Approved: Sun-Spots@rice.edu
Original-Date: Tue, 14 Feb 89 14:14:47 pst
X-Sun-Spots-Digest: Volume 7, Issue 167, message 1 of 15

scott@csis.oz.au (Scott MILTON) writes:

> We have found it necessary to do dumps by piping to dd, instead of using
> rdump. Doing:
> 	rdump 0f tapehost:/dev/nrst1 /dev/rxy0a 
> 	rrestore 0tf tapehost:/dev/nrst1
> fails, while
> 	dump 0f - /dev/rxy0a | rsh tapehost dd of=/dev/nrst1 bs=20b
> 	rsh tapehost dd if=/dev/nrst1 bs=20b| restore 0tf -
> works....

I have an Exabyte connected to a SUN that I've been using for several
months now.  I would like to use it for my MicroVAX but haven't because of
the slow throughput of rdump.  I tried your suggestion of using rsh and dd
to keep the Exabyte streaming and it seems to work.  I was able to dump
and restore files from the MicroVAX disk to the Exabyte connected to the
SUN ( I even used the -i option on restore ).  I used a blocksize of 64k
instead of 20b.

The question I have is how to do a restore when multiple partitions were
dumped from the VAX to the Exabyte via rsh and dd.  For example, on my
SUN, I dump about 11 partitions to one tape on the Exabyte.  To restore a
specific partition, I use "mt fsf {# of dumps to skip}" and then do my
restore.

I tried dumping 2 partitions from the VAX to the Exabyte using rsh and dd
(which seemed to work) but when I tried to do the restore, I was unable to
locate the 2nd partition.  I tried the following:

	rsh tapehost mt -f /dev/nrst9 fsf 1
	rsh tapehost dd if=/dev/nrst9 bs=64k | restore 0tf -

All I got was the first partition that I dumped.  I don't know enough
about dd to understand if this should work or not.  Any information would
be greatly appreciated.

Thanks,

Dave Axness
Quantum Medical Systems
Issaquah, WA
uunet!wor-mein!dave