Here I come from out in left field, unencumbered by the thought process...

It's been a while since I've worked with any SCSI devices but you used 
to have to have a terminator (BTR) at the end of the chain. Without that 
you would get strange behavior.

One way to approach this, especially if you suspect hardware, is to pull 
everything out of the system except what is absolutely necessary to use 
the tape drive. In other words, minimal RAM, the boot drive on a simple 
(non-RAID) controller, no CD, no NIC, bare bones.

Another way is to talk to HP tech support about the tape drive or see if 
their web site says anything about this problem. Maybe they have an 
updated driver. There may be an update for the backup software.

I'm also wondering if you are putting one big file on the tape or many 
small files? Maybe you are hitting one file that is causing problems.

Maybe my guesses will get someone else to reply...

rotbau wrote:
> Hello all,
> 
> I am running SUSE 9.0.  I am having some problems with a recently
> installed HP Surestore DAT 40.  When I try and run a backup, the
> computer freezes, slowly at first and then progressively gets more
> locked up.  Here is what happens.
> 
> Start Backup
> BU software starts the jobs and hits a good xfer rate.  Usually within
> 30-50 seconds of starting the job the backup throughput falls and
> eventually goes to 0.  The tape drive stops receiving data (light
> stops flashing).  The backup software interface still functions but
> becomes increasingly unresponsive.  Same with the GUI interface. 
> Eventually all user interfaces lock up.  If I run a very small backup
> job (like the htdocs directory) it will work fine.  Any larger job
> causes the hang.  No matter how long I wait, the software never
> generates and error message.  Also, nothing in any of the log files I
> checked to say what is happening.
> 
> This box has apache and qmail running on it as well.  When it is
> locking up, I can still access the apache test page text, but the
> graphic won't load.  I can telnet to qmail but it won't send any mail.
> 
> Here is the setup.
> 
> Compaq Smart 2SL attached to 2 x 9 GB drives in RAID 1 and 1 36 GB drive.
> HP DAT is connected to on board Adaptec 7860 controller along with a
> NEC cdrom drive.  The CD is the last device on the chain.
> Backup software tried (both Tapeware and Arkeia).
> All drives appear as expected.  I can format tapes in the drive and
> have been able to work with as expected until I start a backup job.
> 
> I suspect it is a hardware issue.  The 7860 is a ultra/narrow
> controller whereas the DAT drive is a Ultra/LVD drive.  Is it possible
> that this is the cause?  Could the location of the DAT on the cable be
> a problem, should it be last?
> 
> This server also has a 7890 on-board controller that is Ultra/LVD, but
> when I enable it the machine won't boot to the Compaq raid controller.
>  I think I need to disable some stuff in the scsi bios to fix that
> problem, but I haven't had time.  The compaq 2sl also has a second
> channel, but the documentation that came with the dat suggests you
> shouldn't connect it to a raid controller if possible.
> 
> Any suggestions on where to look for this problem would be helpful. 
> Thanks in advance.
> 
> rotbau
> 
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> 

-- 
Eric (Rick) Meyerhoff

_______________________________________________
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