Hooking up A3700AB to an L2000..

[someone_4]

Hello everyone,
I have been asked to hookup an A3700AB auto-raid to an L2000 server.

First I would like to confirm that I need 2 single port wide fast scsi cards part # A4800A.

And then any installation or configuration tips for the cards. Patches #'s for drivers would be nice. I do plan on formating this server with a fresh 11.0 install. Will the install find the cards?


Thanks
Richard

[S.K. Chan · Accepted solution]

Yes, that's what we got here too. The A4800A supports HVD drives. You would want to install those cards on the Turbo slots. One thing to watch out, the card needs an internal scsi terminator which you need to make sure it's installed first. I remembered we could not get the system to see the 12H because we forgot to install the terminator. As long as you got the latest patch bundles when you do the fresh install you'll be fine. I don't think they need any special patches (as far as I can remember).

[A. Clay Stephenson]

Though I don't suggest it, you could get by with a single card and daisy chain the X and Y controllers on the AutoRAID. You, of course, could not then tolerate the failure of a SCSI bus but it is cheaper. Surprising, if you do the typical configuration, the performance with 2 SCSI buses is no better than one. The 2nd just serves as failover; obviously, you are NOT going to do the typical configuration.

Here's what you should do.
1) For each VG that you build, make 2 identically sized LUN's. Despite the myths out there there is no measurable advantage to exceeding 2 LUN's per VG - although things will APPEAR better to tools like Glance.
2) LUNa's primary path should use Controller X (alternate Y) and LUNb's primary path should use Controller Y (alternate X). This will allow you to make full use of both external SCSI paths and all four internal SCSI paths.
3) Each LVOL under this VG should stripe across both LUNS (typically in 64K chunks).

Finally, allocate as little space as possible as LUN's. The idea is to keep the AutoRAID in RAID 1/0 at all times.

I would load the lastest arraymgr software, SCSI patches, VxFS patches, and the AutoRAID firmware.

If configured correctly, it's rather surprising how well these old gals will perform.