topic Re: Reverse Primary/Alternate disk links in Operating System - HP-UX

Reverse Primary/Alternate disk links

jerry1 — Thu, 13 Jul 2006 13:46:00 GMT

I would like to reverse the order of the
primary and alternate link physical disks
listed below. How can this be done easily
or does the vg have to be destroyed and
re-created all over again along with the lv's?

--- Physical volumes ---
PV Name /dev/dsk/c46t2d1
PV Name /dev/dsk/c48t2d1 Alternate Link

PV Name /dev/dsk/c48t2d2
PV Name /dev/dsk/c46t2d2 Alternate Link

Re: Reverse Primary/Alternate disk links

Torsten. — Thu, 13 Jul 2006 13:50:27 GMT

vgreduce the primary, LVM will switch to the alternate. vgextend the removed one and it becomes alternate.

vgreduce vgxx /dev/dsk/c46t2d1
vgextend vgxx /dev/dsk/c46t2d1

you can also use

pvchange -s

to make it the primary, but only until next reboot, not permanent.

Re: Reverse Primary/Alternate disk links

A. Clay Stephenson — Thu, 13 Jul 2006 13:55:54 GMT

There are two approaches. You can vgexport the VG and then vgimport reversing the order of the PV paths or you can do a vgreduce followed by a vgextend.

e.g.
vgreduce /dev/vgXX /dev/dsk/c46t2d1
vgextend /dev/vgXX /dev/dsk/c46t2d1

Man vgreduce, vgextend, vgexport, vgimport for details.

Re: Reverse Primary/Alternate disk links

jerry1 — Thu, 13 Jul 2006 13:58:52 GMT

Cool. It works.

Many Thanks.

Re: Reverse Primary/Alternate disk links

Torsten. — Thu, 13 Jul 2006 14:35:27 GMT

You are always welcome!

Thank you for the assigned points.