PV order in VG

[Stuart Powell]

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

[Torsten.]

How did you order the PVs?

Use vgreduve/vgextend to sort the alternate links.

[Stuart Powell]

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

[Denver Osborn]

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

[James R. Ferguson · Accepted solution]

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...

[Stuart Powell]

Excellent input. Thanks for the confirmation.

Stuart

[Stuart Powell]

I appreciate the input on this problem.

[James R. Ferguson]

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...

[Torsten.]

what's wrong with my answer?