HP SURESTORE 700MX JUKEBOX - Differential SCSI

[Frank Lezaja]

Attempting to connect an HP SureStore 700mx jukebox a new HP server running (Windows 2003 server) with a HP SC11Xe SCSI (Host Bus Adapter) via Differential SCSI using a HP SCSI cable (C2363B) of 10M (33 feet). At boot time the SERVER/SCSI do not see the jukebox, in fact the server hangs right after the SCSI card driver loads? Can we drive the HP SureStore 700mx via Differential SCSI? There is a selection switch on the jukebox next to the cable connections where you select either Single-Ended or Differential. Any ideas?

[Curtis Ballard]

That HBA is Low Voltage Differential and the library is High Voltage Differential. The two are not compatible. HVD cards are really hard to find anymore but if you need to run 10M of cable you'll have to track down an HVD card.

You could switch the library to single ended and it would work with that card but I don't think there is any chance it would work with 10M of cable. A 2 meter should work fine, maybe 5 but 3 is the maximum you really should run with SE.

[Frank Lezaja]

Thank you Curtis for your reply and insight into our problem. I had thought that this could be an issue, but no matter where I looked (SureStore 700mx) manuals, there is no mention of type of SCSI, meaning LVD or HVD. Where did you find this information? And instead of changing the SCSI adapter to HVD, have you used any of the SCSI Expanders / Converters, such as those from (http://www.paralan.com). The reason I ask is because we have no choice and must move the jukebox about 25 feet from the server.

[Curtis Ballard]

When the 700MX jukebox was originally designed there was no such thing as LVD it was just Differential or Single Ended. It's pretty safe to bet with SCSI that if you are working with an older product and it says "Differential" that will be HVD. Because there were two differential standards at one point everybody using LVD was pretty careful to say LVD and that seems to have stuck. I can't recall ever seeing LVD referred to as just "differential".

Yes the 700MX has been used with differential to SE converters. I've personally used a Paralan with an older version of that library.