MSL 2024 Tape Library Ultrim 920 Drive

[Gerald Coates]

I have a MSL 2024 Tape Library with two Ultrim 920 Drives and one drive backs up data at almost 3 times the rate as the other drive. The tape library is attached to a Dell Poweredge 2850 running Windows Server 2003. I've had both drives and the library replaced and still experience the problem.

The library is attached to an Adaptec 39320 SCSI HBA. I tried running test using the HP LTT tools and Symantec Backup Exec. Both show that drive one is slower than drive two. The strange thing is that if I swap the drives, cables and SCSI ports, the problem stays with drive one.

[meloni]

Drive one id doing passthough for the robotic controller.

if you have supervisor software or if you didn't apply the registry option to stop TUR or if you have other polling agents, or services in the hosts, the first drive will have to answer an forward two time the amount of these unsollicited scsi commands, then it will need the double of time for managing and answering these commands then the second drive

[Gerald Coates]

Marino,

Thank you for the information. I wasn't aware of that.