Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!mips!dimacs.rutgers.edu!seismo!beno!black
From: black@beno.CSS.GOV (Mike Black)
Newsgroups: comp.unix.ultrix
Subject: Re: dump under Ultrix 4.1 (DS3100/TK50)
Keywords: dump, 3100
Message-ID: <49552@seismo.CSS.GOV>
Date: 11 Apr 91 00:14:50 GMT
References: <2020@godzilla.tcs.com>
Sender: usenet@seismo.CSS.GOV
Distribution: na
Organization: Center for Seismic Studies, Arlington, VA
Lines: 34

In article <2020@godzilla.tcs.com> jac@zabriskie.berkeley.edu (Gordon Jacobs) writes:
>I just upgraded to Ultrix 4.1 on a DECstation 3100 and when I 
>went to perform a tape backup to TK50, I typed:
>
>	% dump 0u /usr
>
>as usual.  The dump program announced that it would write 10.3
>tapes of the 300Mb partition!  This was based on 1600bpi density
>and when I read the man page, it said that the default was 1600.
>I quit and re-ran the dump using the "d" option to specify 6250bpi
>and the results were more reasonable.  I thought the TK50 had a
>fixed density.  The default under Ultrix 3.1 was such that no 
>density needed to be specified.  Is the dump message just wrong?
>Will it always use the correct density, or what should be specified?
>
>Thanks,
>Gordie Jacobs
> 
I believe that 'dump' assumes it's working with a 9-track.  Seeing as how
the tk50 is a 22 track recorder at 6667bpi you need to fool it some like
this:
dump 0uds 6660 1466 /usr
The 1466 is a correction to 600 feet of TK50 tape at 6667bpi/22track versus
6250bpi/9track.  I've just started doing this myself so no results are
guaranteed, but it should also work well with 'rdump' too.
Maybe someone else can shed some more light.
Mike...


--
-------------------------------------------------------------------------------
: usenet: black@beno.CSS.GOV   :  land line: 407-494-5853  : I want a computer:
: real home: Melbourne, FL     :  home line: 407-242-8619  : that does it all!:
-------------------------------------------------------------------------------