2000-11-12 16:50:02

by jim

[permalink] [raw]
Subject: IDE tape problem in 2.2.17 on Intel SMP

I wrote on Nov 2nd about IDE tapes no longer working in 2.2.17. The
write seems to work fine, but the verify pass causes read errors and
a tar abort.

I tried changing the priority of the tar process to higher than all
others (it was running as a very low priority job and I thought that
might be a contributing factor), but the higher priority did not help.

I tried restoring the last file from the tape. One day it failed with
an "unexpected EOF" error, the next day it restored the file correctly
(even though we got the 12 read errors on the verify pass and tar
aborted).

My conclusion is that the tape write is working. The drive has
hardware read after write verification, so I kinda thought this was
the case. But IDE tape reads appear to be flakey on an active SMP
setup (Intel). This problem started the day we switched from 2.2.16
to 2.2.17, without any other software or hardware changes.

If I can be of any further help, let me know.

Thanks,
Jim Wilcoxson
Owner, http://www.rubylane.com


2000-11-13 15:47:10

by Camm Maguire

[permalink] [raw]
Subject: Re: IDE tape problem in 2.2.17 on Intel SMP

Greetings! You're not running the ide patches, are you? We're
running 2.2.17 with the patches, and have found that we must use the
ide-scsi interface to get verifiable backups. We still get apparently
harmless error messages in the logs though.

Here are our modules.conf entries:

pre-install ide-scsi echo ide_scsi:1 > /proc/ide/hdc/settings
post-install ide-scsi echo using_dma:0 > /proc/ide/hdc/settings
pre-install ide-tape echo ide_scsi:0 > /proc/ide/hdc/settings
pre-install st /sbin/modprobe -k ide-scsi

We then use /dev/nst0.

I believe these sysctrl parameters are only available with the ide
patches. You might be able to replicate the functionality with module
options if you're not using the patches.

Take care,

[email protected] writes:

> I wrote on Nov 2nd about IDE tapes no longer working in 2.2.17. The
> write seems to work fine, but the verify pass causes read errors and
> a tar abort.
>
> I tried changing the priority of the tar process to higher than all
> others (it was running as a very low priority job and I thought that
> might be a contributing factor), but the higher priority did not help.
>
> I tried restoring the last file from the tape. One day it failed with
> an "unexpected EOF" error, the next day it restored the file correctly
> (even though we got the 12 read errors on the verify pass and tar
> aborted).
>
> My conclusion is that the tape write is working. The drive has
> hardware read after write verification, so I kinda thought this was
> the case. But IDE tape reads appear to be flakey on an active SMP
> setup (Intel). This problem started the day we switched from 2.2.16
> to 2.2.17, without any other software or hardware changes.
>
> If I can be of any further help, let me know.
>
> Thanks,
> Jim Wilcoxson
> Owner, http://www.rubylane.com
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to [email protected]
> Please read the FAQ at http://www.tux.org/lkml/
>
>

--
Camm Maguire [email protected]
==========================================================================
"The earth is but one country, and mankind its citizens." -- Baha'u'llah

2000-11-13 15:51:10

by jim

[permalink] [raw]
Subject: Re: IDE tape problem in 2.2.17 on Intel SMP

Thanks for the info. We're running 2.2.17 from http://www.kernel.org w/o
any patches.

Jim

>
> Greetings! You're not running the ide patches, are you? We're
> running 2.2.17 with the patches, and have found that we must use the
> ide-scsi interface to get verifiable backups. We still get apparently
> harmless error messages in the logs though.
>
> Here are our modules.conf entries:
>
> pre-install ide-scsi echo ide_scsi:1 > /proc/ide/hdc/settings
> post-install ide-scsi echo using_dma:0 > /proc/ide/hdc/settings
> pre-install ide-tape echo ide_scsi:0 > /proc/ide/hdc/settings
> pre-install st /sbin/modprobe -k ide-scsi
>
> We then use /dev/nst0.
>
> I believe these sysctrl parameters are only available with the ide
> patches. You might be able to replicate the functionality with module
> options if you're not using the patches.
>
> Take care,
>
> [email protected] writes:
>
> > I wrote on Nov 2nd about IDE tapes no longer working in 2.2.17. The
> > write seems to work fine, but the verify pass causes read errors and
> > a tar abort.
> >
> > I tried changing the priority of the tar process to higher than all
> > others (it was running as a very low priority job and I thought that
> > might be a contributing factor), but the higher priority did not help.
> >
> > I tried restoring the last file from the tape. One day it failed with
> > an "unexpected EOF" error, the next day it restored the file correctly
> > (even though we got the 12 read errors on the verify pass and tar
> > aborted).
> >
> > My conclusion is that the tape write is working. The drive has
> > hardware read after write verification, so I kinda thought this was
> > the case. But IDE tape reads appear to be flakey on an active SMP
> > setup (Intel). This problem started the day we switched from 2.2.16
> > to 2.2.17, without any other software or hardware changes.
> >
> > If I can be of any further help, let me know.
> >
> > Thanks,
> > Jim Wilcoxson
> > Owner, http://www.rubylane.com
> > -
> > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> > the body of a message to [email protected]
> > Please read the FAQ at http://www.tux.org/lkml/
> >
> >
>
> --
> Camm Maguire [email protected]
> ==========================================================================
> "The earth is but one country, and mankind its citizens." -- Baha'u'llah
>