topic Re: hardware question in Operating System - HP-UX

hardware question

Asad Malik — Fri, 16 Nov 2001 21:20:39 GMT

Hi
We have N4000 with 4 controllers. Two being used for AutoRaid and are untouchable. other two are being used fro two DLT 7000 each. We want to put two DLT's on one controller and use the other for SC10 disk unit. Is this layout possible and will there be any issue with this like patch requirement, performance, hardware incompatiability etc.

I shall be glad to give more information.

Thanks

Re: hardware question

Michael Tully — Fri, 16 Nov 2001 21:25:39 GMT

Hi,

It is not recommended placing two DLT drives on the same SCSI chain. You will not get enough throughput to the drive to keep it streaming at the right rate.

-Michael

Re: hardware question

Craig Rants — Fri, 16 Nov 2001 21:27:11 GMT

We have N4000 with 4 controllers. Two being used for AutoRaid and are untouchable. other two are being used fro two DLT 7000 each. We want to put two DLT's on one controller and use the other for SC10 disk unit. Is this layout possible and will there be any issue with this like patch requirement, performance, hardware incompatiability etc.

From what you say I don't see a problem doing this. The DLT's should be ok, just make sure that they have different id's. You may see less of a throughput if you have two tape writes going at once, but it should not be a big deal. As far a performance you are probably going the best way possible for your hardware. I don't know about any patches or incompatabilities, I would say go for it.

Good Luck,
C

Re: hardware question

Craig Rants — Fri, 16 Nov 2001 21:29:13 GMT

Michael,
Why is that, most jukeboxes with multiple drives are on a single channel. I don't see any difference between that and what Asad wants to do. Please enlighten.

C

Re: hardware question

Darrell Allen — Fri, 16 Nov 2001 21:33:38 GMT

Hi,

You should be okay with 2 DLT 7000 drives on one scsi controller by themselves. I don't have the specs at the moment but 2 DLT7000s can be kept streaming on a FW scsi without problem. That was our standard configuration at my last job (lots of big STK libraries in mixed AIX, Solaris, and HPUX environment).

If you have disks on the same chain then you will see a performance hit.

Darrell

Re: hardware question

Michael Tully — Fri, 16 Nov 2001 21:45:47 GMT

Well I thought I'd look some more... I'll get my size 11 out of my backside now.... I was always taught to put DLT's on separate controllers due to the throughput... Anyway I read this document that should clear everything up.

http://www.hp.com/cposupport/information_storage/support_doc/lpg51246.html

Cheers
-Michael (always willing to admit a mistake!)

Re: hardware question

Asad Malik — Fri, 16 Nov 2001 21:53:00 GMT

I was talking to HP and they suggest that two dlt4000 can be used with one controller but dlt7000 and dlt8000 should be attached to respective controllers. Attaching two DLT 7/8000 to one controller will cause all kind of time out errors.

Re: hardware question

Craig Rants — Fri, 16 Nov 2001 22:35:37 GMT

Thanks for the info Asad, give yourself 10 points.

C