On Thu, Sep 30, 1999 at 09:08:01AM +0100, Roland Boden wrote:
> One scsi host adapter Adaptec 1542 with the following devices:
> |------------+--------------------------------|
> |id |device |
> |------------+--------------------------------|
> |0 |HD: |
> |------------+--------------------------------|
> |2 |Tape: |
> |------------+--------------------------------|
> |3 |Cdrom: |
> |------------+--------------------------------|
> |7 |host adapter |
> |------------+--------------------------------|
>
> I setup everything using the "SCSI checklist" from SuSE. I also disabled "sync
>negotiation" and
> "allow disconnect" in the host adapter BIOS.
WHICH IS A BAD IDEA. (Did you write this in the prior e-mail to me? I must
have overlooked it.)
Note that disallowing disconnection forces your SCSI devices to monopolize
your SCSI bus. No problem for a harddisk, which can transfer data rather
immediately. But with your tape, you ask for trouble.
(Does the SuSE SCSI checklist tell you to disable disconnection? I have to
tell them to change this!)
> Sometimes when running a backup program the sytem crashed and could only be rebooted
>by a
> hardware reset. The file system check reported a lot of errors and tried to repair
>but very
> much files were destroyed or the file system couldn't even be repaired.
The tape monopolizes your SCSI bus and your harddisk times out ...
> OK, thats history because I now have a different host adapter. Kurt
> Garloff told me that the Adaptec host isn't very reliable and may cause
> problems like that I have. So I bought a Tekram host adapter. The
> configuration now is:
In general, ISA devices may cause trouble, because it's a broken arch.
> scsi host apadter 0: Adaptec 1542 (as before but with no devices attached)
> scsi host adapter 1: Tekram DC390U with the following devices:
> |------------+--------------------------------|
> |id |device |
> |------------+--------------------------------|
> |0 |HD: |
> |------------+--------------------------------|
> |2 |Tape: |
> |------------+--------------------------------|
> |3 |Cdrom: |
> |------------+--------------------------------|
> |7 |host adapter |
> |------------+--------------------------------|
>
> I again disabled the "sync negotiation" and "allow disconnect" for ID 2 and 3.
Again a very bad idea to disallow disconnection. (Disallow Sync Nego might
help, if you got problems with too long cable or bad termination, though.
But that does not seem to be your problem.)
> When trying to read a tape (which was written by the Adaptec host) I get
> Input/Output Errors and thus the tape cannot be read. I didn't try to
> write something to the tape.
> For now I can give you some examples of the syslog (see attachment "messages").
> If you need more information ask me.
>
> At the moment I connect the tape to the Adaptec host, the disk and cdrom to the
>Tekram host.
> Otherwise I cannot run the backup. But I really would like to know why it is
>possible to crash
> a system like Linux by just reading a DAT tape (I did it three times in one day).
>And I also
> think it should be possible to run a normal scsi device on a normal scsi host
>apapter,
> shouldn't it?
>
> I am hopefully awaiting your suggestions, opinions, questions!
PLEASE ALLOW DISCONNECTION and try whether your trouble continues. I'd bet
not.
--
Kurt Garloff <[EMAIL PROTECTED]> Wuppertal, FRG
PGP2 key: See mail header, key servers Linux kernel development
SuSE GmbH, N�rnberg, FRG SCSI drivers: tmscsim(DC390), DC395
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