topic Re: Changing the disk pathing for a mounted filesystem. in Operating System - HP-UX

Changing the disk pathing for a mounted filesystem.

CSK Auto — Sat, 28 Oct 2006 00:40:04 GMT

Hi,
I have an hp 4000 RP7400 running 11.00 that is connected to a SAN via a A6795 HBA card. The SAN manager is reporting that the volume group vgd240aps2 is not on its perferred path. The disk array vendor has asked that I make the following change at the OS

1. Remove the primary path and move the alternate up with the following
command:

vgreduce /dev/vg01 /dev/dsk/c2t1d0

2. Verify the alternate is now the primary with the following command:

vgdisplay

3. Enter this command:

vgextend /dev/vg01 /dev/dsk/c2t1d0

4. Enter the following command to see if it shows c6t0d0 as the primary
and c2t1d0 as the alternative path.

vgdisplay

I don't have a problem doing this but the volume group that I need to change is a mounted filesystem. Is there a risk to making the change listed? The Volume group contains the /home directory which is always busy so it can't be unmounted.

Please advise...

Thanks in advance for your help
Gwenn

Re: Changing the disk pathing for a mounted filesystem.

RAC_1 — Sat, 28 Oct 2006 01:05:47 GMT

You even do not need vgreduce. to change to alternate path (making it primary path) you can just use pvchange -s
man pvchange for details and syntax.

Re: Changing the disk pathing for a mounted filesystem.

CSK Auto — Sat, 28 Oct 2006 01:14:03 GMT

so if I have the following physical disk this is the what I would enter to change the path?

PV Name /dev/dsk/c24t0d1
PV Name /dev/dsk/c22t0d1 Alternate Link
PV Status available
Total PE 8446
Free PE 2

pvchange -s /dev/dsk/c24t0d1

Will this automatically change the alternate to be the primary? Do I still need to do the vgextend? Does it matter if it is mounted filesystem that is part of the volume group?

Thanks for the quick response
Gwenn

Re: Changing the disk pathing for a mounted filesystem.

RAC_1 — Sat, 28 Oct 2006 01:17:59 GMT

pvchange -s /dev/dsk/c22t0d1

primary becomes alternate and alternate becomes primary. No need to do anything else.

Re: Changing the disk pathing for a mounted filesystem.

CSK Auto — Sat, 28 Oct 2006 01:22:31 GMT

excellent thanks... much easier that way

Have a good evening.

Re: Changing the disk pathing for a mounted filesystem.

CSK Auto — Sat, 28 Oct 2006 01:24:36 GMT

thread can be closed

thanks again for the quick response.