From: utzoo!decvax!harpo!seismo!rocheste!ritcv!kar
Newsgroups: net.unix-wizards
Title: Re: Flames on system backups
Article-I.D.: ritcv.312
Posted: Tue Apr 19 19:51:10 1983
Received: Fri Apr 22 06:47:16 1983
References: rlgvax.269

Regarding the discussion of how to restore from tapes that have multiple dumps
on them:

	Many people (ourselves included) have implemented an F option in 
"restor" to automatically space the tape to the proper dump when several have
been recorded on the reel.  Others retort that this is not necessary; all you
need to do is "mt fsf N", do the restor, ^Z, "mt fsf N", %1, then enter the
reel number, and you're all set! (How intuitively obvious!)

	Here's what we used to do on our V7 systems (no ^Z, thank you!) before
we got 4.1bsd:

dd if=/dev/nrmt0 of=/dev/null bs=20b files=N	# skip N files on the tape
(sleep 60; dd if=/dev/nrmt0 of=/dev/null bs=20b files=N) &
restor xf /dev/rmt0 file ...

	The "restor" command would read the bit maps and directories from the
tape and rewind it.  It would then print the i-numbers and names of the files
it found on the tape, and ask the operator to "mount the desired volume".  The
operator simply waited until the "sleep" interval elapsed, at which point the
second "dd" positioned the tape back to the right spot.  Hitting "return"
completed the successful restore!

	Not afraid to say
	Not afraid to admit to being a hacker:

	Ken Reek, Rochester Institute of Technology
	ucbvax!allegra!rochester!ritcv!kar