Help with DS2120 and 300Gb disks

[Bob Viveney_1]

Hello
I have an rp8420 running 11.23 0609 with 4 A7173A SCSI adapters connected to 4 DS2120 disk systems and the disk systems are populated with A7384A 300Gb U320 disks and terminators. I used the mptconfig command to set the transfer rate to Ultra160. However, it seems to auto-negotiate down to Ultra2/wide for some reason.

But my problem is that I can not create file
systems on all the disks in the array and the problem varies from one array to another. So consider one particular array where I have 4 disks in it. I can create a file systems on 2 of these disks, the ones in slot 1 and 3. But when trying to create a file system on the disks in slot 2 and 4 I get errors such as

"Driver initiating SCSI bus reset. Condition cleared, no intervention required." from syslog

or a major warning from resdata about software configuration
or "pvcreate: writing LVM record: I/O error".

So I tried swaping the disks in slots 1 and 2. I was able to create a file system on the disk in slot 1 but not slot 2 again, leading me to believe I can eliminate the disk itself as being the problem.

On other disks in this system I have similar problems but with different disks/slots. For example, another array has 3 disks successfully formatted but I can not format the fourth.

What else to try? What more information is needed?

I incluced the output from the Event Monitor Service as an attachment.
Thanks
Bob

[Mike Shilladay]

Hi Bob,

Are you daisy chaining these disks? Also do you have them connected for alternate links?

My initial repsonse would be that there could be a SCSI conflict and/or bus problems. Do you have the correct cables and terminators in place and are they all plugged in.

I would suggest for problem identification that you focus on one DS2120 and one interface and build up from there.

If you have the disks connected for alternate links you will need to set one of the SCSI cards to an ID other than 7. (Usually 6 is good, 7 is the highest priority, 6 next, then 5 down to zero, then 15 down to 8 the lowest priority 8 is the lowest priority). Ensure no conflict with SCSI ids on the bus.

You may also want to check that all disks are latched home.

If it were just one ds2120 I would suggest H/W fault, but all of them suggests configuration problem.

Hope that helps,

Mike.

[Bob Viveney_1]

Hi Mike
No, I am not daisy chaining these enclosures together. Each controller SCSI cable goes to its one enclosure and each enclosure is by itself with a terminator.
I'm not sure what you mean by alternate links. Each enclosure has the switch on the back set to 'B' for using id's 8,10,12,14.
Each controller is using SCSI id 7.

I have pulled out and reseated disks several times so I believe they are seated OK.

I am going to check the terminators but I assume they came from the factory with the correct terminators. I'm going to also remove the cable from one of the enclosures, inspect it for bent pins and reinstall it to see if that helps.

Thanks for your response. Any other ideas?
-Bob

[Mike Shilladay]

Hi Bob,

By alternate links I meant two SCSI controllers to each DS2120, therefore you have to set a different SCSI ID to each controller.

Are you going to try just one controller and one ds2120 and see what the results are?

Mike.

[Bob Viveney_1]

Hi
I pulled the cable and terminator off the DS2120 and reseated it tightly and was able to create the physical volumn on each of my 4 disks. So I assume it was a fault cable or terminator connection.
-Bob