topic PV order in VG in Operating System - HP-UX

PV order in VG

Stuart Powell — Fri, 30 May 2008 13:27:29 GMT

I have a system running HP-UX 11i V1. I recently adjusted the connection order of the PV's for a particularly busy volume group. I want some reassurance that after I reboot the system the order will remain the same.

Any experience?

Stuart

Re: PV order in VG

Torsten. — Fri, 30 May 2008 13:33:56 GMT

How did you order the PVs?

Use vgreduve/vgextend to sort the alternate links.

Re: PV order in VG

Stuart Powell — Fri, 30 May 2008 13:36:23 GMT

That is correct. I'm running a Veritas filesystem, but not load balancing.

Re: PV order in VG

Denver Osborn — Fri, 30 May 2008 13:36:47 GMT

How did you change the order? Was it done via 'pvchange -s /dev/dsk/new_pri_path' or through a vgreduce/vgextend?

The 'pvchange -s' would not survive a reboot. To change the order of pvlinks and have it persistent, you'd want to vgreduce/vgextend the pvlinks or export and import the vg to get things in the order you'd like.

-denver

Re: PV order in VG

James R. Ferguson — Fri, 30 May 2008 13:39:00 GMT

Hi Stuart:

The order will remain if you use 'vgreduce' and 'vgextend' to make your assignments.

Another way is to 'vgexport' the volume group with its 'outfile' option to capture the 'pv_links'. Edit the order of the alternate links in that file to your taste, and use the modified file as the 'infile' to 'vgimport'. See the manpages for more information.

Look too at the 'pvchange' command and its 'autoswtich' documentation.

Regards!

...JRF...

Re: PV order in VG

Stuart Powell — Fri, 30 May 2008 13:40:44 GMT

Excellent input. Thanks for the confirmation.

Stuart

Re: PV order in VG

Stuart Powell — Fri, 30 May 2008 13:41:12 GMT

I appreciate the input on this problem.

Re: PV order in VG

James R. Ferguson — Fri, 30 May 2008 13:41:58 GMT

Hi (again) Stuart:

> I'm running a Veritas filesystem, but not load balancing

Do you mean that you are running VxVM and not LVM?

With LVM, alternate links (pv_links) are *not* load-balanced. Rather they are for high-availability only.

Things change radically on 11.31 (11iv3).

Regards!

...JRF...

Re: PV order in VG

Torsten. — Fri, 30 May 2008 13:42:17 GMT

what's wrong with my answer?