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Date: Tue, 03 Jun 2003 08:51:59 -0600
From: "Justin T. Gibbs" <gibbs@scsiguy.com>
To: Kern Sibbald <kern@sibbald.com>, mjacob@feral.com
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cc: freebsd-scsi@freebsd.org
Subject: Re: SCSI tape data loss
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> Hello,
> 
> Dan has now re-run our test of writing to two tapes. In
> this test, he told Bacula not to attempt to re-read the
> last block written, so Bacula wrote until -1 with errno=ENOSPC
> was returned, wrote two EOF marks then put up
> the next volume.

Bacula is supposed to start the process of a tape change as soon
as the amount written is less than what you intended to write.
Ignoring the short write and waiting until you hit ENOSPC guarantees
you will hit PEOM, since the LEOM is only reported once.  The tape
driver expects that you know what you are doing if you go on writing.

--
Justin