David Douthitt writes:

> I'm trying to multipath a LVM volume on HP-UX 11i v3 with
> ServiceGuard. The disks are on an EMC array, and there are two links
> to the disk on each of two ServiceGuard cluster nodes.
>
> One (data) disk is currently configured with logical volumes and so
> forth. Attempting to use vgextend to add a second path results in:
>
>
> # vgextend -g pvg1 /dev/clvol2 /dev/dsk/c6t0d1

I think you are supposed to use the new device names ("ioscan -kfnN")

> Verification of unique LVM disk id on each disk in the volume group
> /dev/clvol2 failed.
> Following are the sets of disks having identical LVM disk id
> /dev/dsk/c7t0d1 /dev/dsk/c6t0d1

Could it be that both devices are alternate paths to the same disk?

>
>
> What am I missing? The initial vgcreate did not have a -g option
> (that was before I knew about that option). I created /etc/lvmpvg
> with the appropriate disk in it, but the message above is what
> results.

I thing PVGs are unrelated here.

>
> I don't know scsimgr, and I'm still learning ServiceGuard. What am I
> missing here?

Maybe try a pvdisplay to find out more details of the disks.
BTW: In our environment each LUN has four paths to consider ;-)

Ulrich

I found a lot of helpful information in the HP ITRC Forums. I'll try to
fill in here.

In article <87fxz77vrv.fsf@pc9454.klinik.uni-regensburg.de>,
Ulrich.Windl@RZ.Uni-Regensburg.DE says...
> David Douthitt writes:

> I think you are supposed to use the new device names ("ioscan -kfnN")
>
> > Verification of unique LVM disk id on each disk in the volume group
> > /dev/clvol2 failed.
> > Following are the sets of disks having identical LVM disk id
> > /dev/dsk/c7t0d1 /dev/dsk/c6t0d1
>
> Could it be that both devices are alternate paths to the same disk?

They are - as it should be. Using pvlinks one is supposed to add the
second disk to the volume group to activate multipathing. HP-UX 11i v3
has intrinsic multipathing; no vgextend necessary.

> I thing PVGs are unrelated here.

One HP document suggested creating a physical volume group (PVG) for
each disk. Again, though, HP-UX 11i v3 uses its intrinsic multipathing.

> Maybe try a pvdisplay to find out more details of the disks.
> BTW: In our environment each LUN has four paths to consider ;-)

Same here, actually: two from cluster node 1, and two from cluster node
2 :-P

For seeing the new volume names, I was pointed to:

ioscan -m dsf

For seeing the state of LUN pathing, I was pointed to:

scsimgr get_info -D /dev/rdisk/disk## all_lpt

Fantastic place for HP-UX information, those ITRC Forums.... The
relevant thread is:

http://forums1.itrc.hp.com/service/f...r.do?threadId=
1177297