topic Re: disk not detecting in Operating System - HP-UX

disk not detecting

Pradeep_3 — Wed, 06 Apr 2005 02:18:11 GMT

Hi all,

We are having two D-class servers with 32 bit
HP 11i os.We are trying to configure MC-service guard on these two nodes.Prior to that we want to check a common storage which can be shared by these above two nodes.
From the above one node we are able to access the storage but when we start another node,
it didn't detect and the other one also get hanged.
The error message what we are getting from dmesg output is attached.

Re: disk not detecting

Slawomir Gora — Wed, 06 Apr 2005 02:25:01 GMT

Hi,

when you connect shared storage you must set
different SCSI ID for controlers on both nodes.
Ex:
node 1 has default SCSI ID - 7
for node 2 set SCSI ID - 6

If you haven't set scsi id symptoms can be similar to yours.

Re: disk not detecting

melvyn burnard — Wed, 06 Apr 2005 03:08:54 GMT

This looks like a SCSI ID conflict.
One way to test is to disconnect the storgae from the node where it IS visible, and retry with just the connection to the second node. If this all works fine, then you more than likely have both scsi cards set to the same address, or there could be termination issues.
What is the model of the shared storage you are using,?

Re: disk not detecting

Pedro Cosmen — Wed, 06 Apr 2005 04:58:14 GMT

Hello Pradeep,

You maybe have the same SCSI address in both SCSI adapters, so you have an duplicate SCSI-ID in your SCSI chain. Check the SCSI cards, and change the SCSI-ID in one of them, so it will not match any other device (disk, tape, card,...) in the same SCSI chain. This can be done by an CE by changing the DIP Switches in the card.

Regards.

Re: disk not detecting

Kent Ostby — Wed, 06 Apr 2005 05:11:58 GMT

To clarify, the reason that this is a problem is because of the shared bus concept used in ServiceGuard.

By default all SCSI cards come with an ID of 7.

This works great as you test each machine seperately with the disks you want to use or even one at a time while they are physically connected since only one card is active on the bus in these scenarios.

It is not until everything is hooked together AND booted that you will start to see the problem.

The fix is as described above by the other posters.

Best regards,

Oz

Re: disk not detecting

Geoff Wild — Wed, 06 Apr 2005 08:10:31 GMT

99% sure this is scsi conflict with shared storage.

As others have said - you must change the scsi id of the card on one of the nodes from the default of 7 to say 6 (or what ever is free and not assigned to a disk).

Rgds...Geoff