firmware update = performance loss??

[Joe Correia]

I one of a pair of DLT8000 drives die on me and I replaced it. On the advice of a compaq engineer I updated the firmware on the older drive to match the newer one and noticed that my backup speeds have been severly reduced? I'm running Backup Exec 8.6 and used to get over 300mb\min now I get 85mb\min?

[Joe Correia]

I forgot to add this:
I'm running a TL891dlx

[Eugeny Brychkov]

DLT8000 product number -?
Old firmware version -?
New firware version-?
ANY other changes were made besides drive replacement and firmware upgrade -?
HP LTT support ticket - please attach to your next reply http://www.hp.com/cposupport/information_storage/support_doc/lpg50128.html
Eugeny

[Joe Correia]

It's a Compaq TL892dlx mini-library with 2 Compaq 40/80GB DLT LDRV0250.
New Firmware Rev. 0250 v80
Old Firmware Rev. ???? v42

Compaq tech had me reset the library to factory defaults but I believe we were running it that way to begin with.

thanks

[Eugeny Brychkov]

Joe, unfortunately I'm not familiar with this CPQ library, but anyway info you posted will help CPQ experts. I believe in worst case you can downgrade firmware to that level you had before.
If these drives are on the same bus, and one drive got replaced: so SCSI chain was 'touched'. Please check if all cables are ok, terminators are in place and there're no bent pins. You also can disconnect new drive off the bus and run with only one drive to check if new drive had influence on the whole library bus speed
Eugeny

[David Ruska]

Joe,

If you can collect a support ticket with HP LTT, we can look at the drive error logs, and see what (if any) events are being logged. They may help explain the drop in performance.

Also, do you know what block size you are using? When we tested newer versions of DLT8000 drive firmware, we noticed an increased sensativity to small block sizes, which resulted in lower performance. The recommendation is 32K or higher.

To see if the problem follows the firmware version for certain, you can use LTT to downgrade the firmware, altough we have not posted all of the older versions of drive firmware for the CPQ libraries. LTT was just recently changed to support the legacy CPQ products.

I can get the v42 firmware and have it put into LTT firmware within a few days, and I could then email it to you. If you want to try that, send an email to ltt_team@hp.com, and I can reply with the firmware.

You will also need a password to do the downgrade - I can email that to you at the same time.

Dave
LTT Team

[Joe Correia]

I will have to double check all the cabling but it was very simple to replace the drive so I don't imagine that I bent any pins. However it's worth going over it again.
Also since the re-install the Backup Exec hardware settings were back to default which is 32k I have bumped this up to 64k to see if it helps.
I will try to generate a support ticket tomorrow (Friday) and put it up here.

thank you for the response.

JOE