StorageWorks DAT 72 internal SCSI problems

[RitchieT]

Hi there,

I have an HP StorageWorks DAT 72 internal SCSI tape drive which I am having some trouble with. It appears to have been installed correctly, recognising the drivers and showing up in device manager as working fine. However when trying to use it with Symantec Backup Exec 9.1 (the drive is on their hardware compatibility list) it shows up as there being no tapes in the drive. I thought this was probably a Backup Exec issue so I made sure that the drive was using the HP drivers again and then used the HP backup software which resulted in the diagnostics saying there was an I/O error.

After this I installed HP StorageWorks library and tape tools which originally picked up the drive but stated that there was no media in it. However now when I do a scan it comes up that “the device is not responding to commands from the host machine”. I can verify that there is power and the SCSI cable is properly seated. The drive is showing up in device manager even though library and tape tools is presenting me with this message.

Any ideas or suggestions would be greatly appreciated. I have listed some useful information below:

Operating System – Windows Server 2003 SBS

Tape drive – HP StorageWorks DAT 72 internal SCSI drive.

Tape drive firmware and drivers are all up to date.

SCSI card – LSI Logic PCI-X Ultra320 SCSI Host Adapter

Many thanks,

Ritchie

[thomasr]

I don't see the LSI card listed by HP as a supported HBA.  It's possible it doesn't have tape drive support.

Can you verify from the LSI site that it does support tape drives?

Supported HP controllers are listed from the legacy http://www.hp.com/go/connect site, or here:

http://www.hp.com/products1/storage/compatibility/tapebackup/ISS/index.html

Also, since you've bounced from one application to another, make sure that all vestiges of backup products you're not using are removed from your system.   Each one wants to own the tape drive exclusively, and this will cause problems.

[RitchieT]

Thank you for your reply thomasr. I can confirm that the LSI card supports tape drives as it was connected to a Dell tape drive previously and working. The old Dell drive recently broke so we have replaced it with the HP one.

As for applications that were installed. The HP software (I cannot remember the name) has now been completely removed. The only backup software installed now is Symantec Backup Exec (this was used with the previous tape drive).

When I run HP Library and Tape Tools I make sure that I change the driver to the HP one as opposed to the Backup Exec one. I also make sure all Backup Exec services are stopped so they do not interfere.

If I try and run Backup Exec with the HP driver it states that the drive is offline. If I run it using Backup Execs own driver then the drive is no longer offline, but the software never sees a tape in the drive.

Thanks again for your help :)

[Curtis Ballard]

It sounds like there are communication errors when attempting to talk to the drive.  Have you checked the OS logs for any SCSI communication errors?

If you have any around I would recommend you try a different internal SCSI cable and make certain that it is an internal cable with a terminator at the end.  Sometimes on internal configuration a cable is used that does not have built in termination and then things only partially work.

You say your previous tape drive failed - what were the symptoms?  Maybe it was the terminator that failed rather than the drive.  A failing terminator will cause random parity errors or other data communication errors before it gets so bad that it doesn't work at all.

[RitchieT]

Thank you for your reply. The cable and terminator are the brand new ones that came with the drive. I do have the old cable and terminator would you recommend trying that? The old tape drive kept failing backups with lots of different errors. The most common being that the transfer rate was to slow and barley any data was transferred before the time out limit was reached on the backup. Cleaning the drive fixed this temporarily, but the problem would always come back after a few weeks, eventually cleaning the drive would not help anymore. This is when we decided to replace the drive.

[Curtis Ballard]

It doesn't sound like cable and terminator should be a problem then and the problems you describe with the old drive don't sound like the card was going bad.  That sounds like the behavior that might be seen if a head was wearing out, not like SCSI communications at all.  Seemed worth asking though.

I would recommend disconnecting the SCSI cables at every connection and looking to make certain there aren't any bent pins then plug them back in.  It could be that somewhere there was a marginal connection when the cables were first plugged in.  Removing and reseating will usually fix that if it is the problem.

[RitchieT]

Hi Curtis.

I will check over the cable connections next time I am onsite and let you know how things go :)

Thanks again,

Ritchie