topic Re: Disk HW Paths in Operating System - HP-UX

Disk HW Paths

Alan Casey — Tue, 02 Nov 2004 09:28:18 GMT

I have a Clariion EMC 400 and a LUN attached to HP-UX 11.i

The hardware path to the disk was:
0/4/0/0.97.4.19.0.0.1

This has now changed to
0/4/0/0.97.4.19.0.0.2

And I'm unable to use it as the powerpath software holds the old address.

I have a call open with EMC about this, but was wondering if anyone knows what the last digit of the hardware path relates to?
Or if anyone has had a similar problem.

The path changed as I changed the default SP path to the SAN and then changed it back to the original.

Re: Disk HW Paths

Patrick Wallek — Tue, 02 Nov 2004 09:44:25 GMT

Well, with most arrays the last digit of the patch refers to the LUN on the array. EMC could very well be different though. Everything I've seen so far has the last digit, possibly the last 2 or 3 digits, representing the lun.

Re: Disk HW Paths

Sanjay_6 — Tue, 02 Nov 2004 09:52:34 GMT

Hi Alan,

The last digit in the path normally refers to the lun id. it is surprising to see the lun id got changed this way unless it was reassigned using the sdr ( the emc disk relocator).

Hope this helps.

Regds

Re: Disk HW Paths

Steven E. Protter — Tue, 02 Nov 2004 09:56:35 GMT

It is possible to renumber instances of hardware within reason. /dev/dsk/c5t6d0 can be changed.

See this doc:
http://www1.itrc.hp.com/service/cki/docDisplay.do?docLocale=en_US&admit=-682735245+1099407378919+28353475&docId=200000067424466

SEP