LTO Driver performance

[Luis Ramírez V.]

We have an LTO Ultrium-1 215 internal installed in a Proliant ML570 G1. The tape is attached to a Ultra320 HBA, but when I check the tape using the L&TT health, it says the following:

"The current SCSI configuration is likely to be limiting the performance of the drive.
Please check that your HBA is the correct type for the drive and that the cabling is good.
The SCSI configuration referenced is the one for which device analysis was run and/or the support ticket was pulled.
If this is not via your backup server then you may not have an issue.
Current SCSI transfer rate limited to: 20 MB/sec. Recommended: 80 MB/sec. or better
The drives hardware compression algorithm is currently switched off.
This was probably set by the backup software.
The drive's setup has not been altered."

We used the NTBackup utility, but our plans are change it. I don't know if this problems are because the NTBackup or any parameter in the HBA.

Maybe somebody can give me a light about a way to try to increase the tape performance.

Thanks for all your help.

Luis Ramírez V.

[Marek Nelec · Accepted solution]

Check if your SCSI cable is properly terminated. You should use 68-pin SCSI cable terminated with LVD/SE terminator. If your terminator simply reads "SCSI", not "LVD/SE", that would be the problem.

[Luis Ramírez V.]

I'll check the HBA cable. The 215 is internal and I installed a different tape backup, a external Ultrium3 920 and the behavior was the same. Maybe the internal cable affects the external tape?

Thanks again for all your help.

[Luis Ramírez V.]

The cable that I used to connect the external tape is C2362B, that, according to HP, is SCSI LVD. Is it right for the tape?

[Marek Nelec]

Luis, if you are using dual channel SCSI HBA, then you can have internal and external drive connected to the same HBA, but to two different channels. If your SCSI HBA is a single channel , but with internal and external connectors, then you should connect devices _EITHER_ to the external _OR_ to the internal connector. The cable that you mention is 68-pin VHDCI to 68-pin HD D-sub EXTERNAL cable. It's compatible with LVD devices, but the device should still be terminated with LVD terminator, regardless if it is an external or internal device. So if you have both internal and external drive connected to the same HBA disconnect one of them, check the terminator and then check if L&TT still says something about limited performance of the SCSI channel.

[Luis Ramírez V.]

Thanks for all your help. I'll check for the terminator and try to disconnect the internal tape and using only the external.

[wol_1]

Hi,

I have very similar problem. Ultrium-3 1/8 Autoloader is the only device connected to Ultra320 HBA (Adaptec 39320A none raid). It is connected and terminated with factory cable and terminator supplied by HP common with device. The HBA is configured correctly, firmware and drivers are updated to latest for HBA and Autoloader. The autoloader device works fine but L&TT says the speed is limited to Ultra160.

Regards

[Kim Tørnsø]

Hey
I too, have a similar problem with Ultrium 3-SCSI in a MSL TapeLibrary. Connected to Adaptech 39160 (no other devices connected). All firmware and drives are updated.
L&TT reports the same warnings.
Have you got a solution by now?

[Curtis Ballard]

I see several posts here for speed negotiation issues. I don't know what the cause of the issues is, typically it is an HBA firmware issue, driver issue, or cabling issue.

I would try a few different driver revisions and check to see if there are different revisions of firmware for the HBA if there aren't any obvious cabling issues. Feel free to post if you find something that works. If it is an HBA driver or tape drive we can go back to the vendor and ask them to fix it.

Regardless of the cause, an LTO Ultrium 1,2, or 3 drive running at U160 will perform at it's maximum rate in most environments so I wouldn't be too concerned about U160 with those drives.

[Kim Tørnsø]

Hello Curtis
Here are some more informations:
The SCSI cable is delivred with the the Library - compaq spare: 110941-001.
The terminator is MSKL R800-01A Ultra320 LVD/SE.
To me it seems that both cable and terminator are OK!
The driver and firmware for the Adaptec 39160 are up to date.
To me it seem more and more like a combatibility issue between Adaptec and HP!