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From: tyager@maxx.UUCP (Tom Yager)
Newsgroups: comp.unix.i386
Subject: Re: Archive Tapes
Summary: There's another way...
Message-ID: <36@maxx.UUCP>
Date: 8 May 90 00:53:42 GMT
References: <29490@cup.portal.com> <1990May3.133709.386@orfeo.radig.de>
Organization: MAXX: Tom Yager's UNIX lab, Amherst, NH.
Lines: 35

In article <1990May3.133709.386@orfeo.radig.de>, peter@orfeo.radig.de (Peter Radig) writes:
> Dante_A_Nicolello@cup.portal.com writes:
> >I am having two problems with an Archive 60 meg Fastape.
> >Problem one:
> >        Tape does not stream.
> 
> Use the GNU tar with a appropiate blocking factor (I use -b2000, i.e.
> 1 MB buffer).
> Peter Radig
> USENET: peter@radig.de  or:  uunet!unido!radig!peter

I've got a nearly identical configuration running here, except that I've got
a 125MB Archive instead of the 60. Should be the same controller, though. I've
had no trouble getting it to stream to the tape, but be aware of this: The
tape NEVER streams when you do a verbose tar. Each group of lines that kicks
out to the display makes the tape do a start/stop.

Instead of "tar cvf /dev/rct0 /foo", try "tar cf /dev/rct0 /foo", or redirect
the output to a file ("tar cvf /dev/rct0 /foo >/tmp/filelist") if you want tar
to move faster.

If that doesn't work, you can up the blocking factor of tar by piping it
through dd, to wit: "tar cf - /foo | dd of=/dev/rct0 obs=262144". I've seen
some drives that take mysterious write errors on some block sizes, so this
may take some experimentation.

Good luck!
(ty)


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