*BSD News Article 80011


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From: j@uriah.heep.sax.de (J Wunsch)
Newsgroups: comp.unix.bsd.freebsd.misc
Subject: Re: SCSI tape block size
Date: 5 Oct 1996 20:35:56 GMT
Organization: Private BSD site, Dresden
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Message-ID: <536grc$ba@uriah.heep.sax.de>
References: <8720ffxq0j.fsf@plm.xs4all.nl>
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Peter Mutsaers <plm@xs4all.nl> wrote:

> I made a backup on SCSI tape, but now I can't read it because I forgot
> the blocksize. Does anyone know how I can see what the blocksize on
> the tape is?

restore(8) will figure it out by itself.

Otherwise, do a:

	dd if=/dev/rst0 of=/dev/null bs=64k count=1

...and see what dd tells you:

j@uriah 158% dd if=/dev/rst0 of=/dev/null bs=64k count=1
0+1 records in
0+1 records out
32768 bytes transferred in 2 secs (16384 bytes/sec)

(Note that 64 KB is the largest blocksize currently supported inside
the kernel by physio(), so there's no use in making the parameter
above larger.)

-- 
cheers, J"org

joerg_wunsch@uriah.heep.sax.de -- http://www.sax.de/~joerg/ -- NIC: JW11-RIPE
Never trust an operating system you don't have sources for. ;-)