From owner-freebsd-bugs Mon Feb 10 17:19:03 1997 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.5/8.8.5) id RAA00774 for bugs-outgoing; Mon, 10 Feb 1997 17:19:03 -0800 (PST) Received: from who.cdrom.com (who.cdrom.com [204.216.27.3]) by freefall.freebsd.org (8.8.5/8.8.5) with ESMTP id RAA00754 for ; Mon, 10 Feb 1997 17:18:59 -0800 (PST) Received: from smtp1.xs4all.nl (smtp1.xs4all.nl [194.109.6.51]) by who.cdrom.com (8.7.5/8.6.11) with ESMTP id RAA29744 for ; Mon, 10 Feb 1997 17:01:14 -0800 (PST) Received: from asterix.xs4all.nl (root@asterix.xs4all.nl [194.109.6.11]) by smtp1.xs4all.nl (8.7.6/XS4ALL) with ESMTP id BAA06730; Tue, 11 Feb 1997 01:59:47 +0100 (MET) Received: from plm.xs4all.nl (uucp@localhost) by asterix.xs4all.nl (8.7.5/8.7.2) with UUCP id BAA00564; Tue, 11 Feb 1997 01:45:12 +0100 (MET) Received: (from plm@localhost) by plm.xs4all.nl (8.8.4/8.7.3) id BAA00374; Tue, 11 Feb 1997 01:00:53 +0100 (MET) Date: Tue, 11 Feb 1997 01:00:53 +0100 (MET) Message-Id: <199702110000.BAA00374@plm.xs4all.nl> From: Peter Mutsaers MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit To: John-Mark Gurney Cc: freebsd-bugs@freefall.freebsd.org Subject: Re: kern/2698: scsi tape driver problem In-Reply-To: References: <199702101950.LAA20963@freefall.freebsd.org> Sender: owner-bugs@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk >> On Mon, 10 Feb 1997 12:49:37 -0800 (PST), John-Mark Gurney >> said: JG> modify /usr/src/sys/scsi/scsiconf.c so that an entry like the "WANGTEK", JG> "5525ES*" JG> but have it be something like: JG> { JG> ..., ..., ..., "DEC", "TZK10", "00B3", JG> ... JG> } JG> then recompile your kernel and see what happens... hope this works... JG> ttyl.. I did this. The result is that mt -f /dev/rst0 status now reports the correct densities: /sys/scsi# mt -f /dev/rst0 status Present Mode: Density = QIC-150 Blocksize = 512 bytes ---------available modes--------- Mode 0: Density = 0x00 Blocksize variable Mode 1: Density = QIC-320 Blocksize variable Mode 2: Density = QIC-150 Blocksize variable Mode 3: Density = QIC-120 Blocksize variable instead of those X3.--- density codes (whatevery they are). Note that at first for mode 2 blocksize 512 was shown, but after some actions this changed into variable. Strange. Indeed, as Joerg Wunsch said, the QIC 150 tape seems to write variable blocks instead of 512 byte blocks. (525MB tapes are always variable blocks. I have no problems at all with them). I can check this as follows: /sys/scsi# restore tf /dev/rst0 st0: block wrong size, 64 blocks residual tape read error: Input/output error but using rst0.1 (act as if QIC 320, whatever that is, which is supposed to have variable blocksize: /sys/scsi# restore tf /dev/rst0.1 Dump date: Tue Feb 11 00:38:03 1997 Dumped from: the epoch Level 0 dump of /var on plm.xs4all.nl:/dev/sd1f Label: none ^Crestore interrupted, continue? [yn] At least I have a workaround for now. I do know that indeed I've had problems in the past with reading QIC 150 tapes under Linux, when written under FreeBSD. I've never encountered such problems under Linux however. I cannot check the behaviour under Linux anymore however since I've removed that from my system. But I think indeed I got error messages under Linux when reading QIC 150 tapes written by FreeBSD, indicating that the blocksize didn't match. Probably Linux tried to read 512 byte blocks from the device. I remember that even experimenting with 'dd if=/dev/st0 bs=10k' didn't help. Which is logical, since 10k to the block device /dev/st0 still results internally into reading 512 byte blocks. -- Peter Mutsaers | Abcoude (Utrecht), | Trust is a good quality plm@xs4all.nl | the Netherlands | for other people to have