How to change Max PE per PV and PE Size (Mbytes) in one vg

[Carme Torca]

Hi,

I have this configuration in one vg.

VG Name /dev/vgshare
VG Write Access read/write
VG Status available, exclusive
Max LV 255
Cur LV 3
Open LV 3
Max PV 16
Cur PV 2
Act PV 2
Max PE per PV 2047
VGDA 4
PE Size (Mbytes) 4
Total PE 4094
Alloc PE 4094
Free PE 0
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0

and I would like to change the parameter
Max PE per PV and PE Size (Mbytes).
Is it possible?
What I have to do?

Thanks a lot of,
Carmen.

[Torsten. · Accepted solution]

Hi,

changing this values is only possible in HP-UX 11.31 using vgmodify.

In all other versions you need to apply the values while creating the VG.

The only choice is to backup the data, destroy the VG, re-create it and restore the data.

[Mridul Shrivastava]

Max PE per PVs are calculated at the time of vg creation based on the PE size and disk size you have.

If you want to make changes to any of them then only way is to recreate the VG with higher capacity disk.

[Emil Velez]

a previous reply mentioned vgmodify..

It was my understanding that vgmodify was available as a unsupported utility. I have used a version on 11.11 and depending on the size of the disk and the LVM headers on the disks it worked most of the time.

This is part of the documentation below that I have for it. You may want to contact the HP response center for the unsupported version for your OS version.

Good luck

NOTE - vgmodify is currently unsupported. This version works on 11.11 only. Download vgmodify from here. The current version 1.27. As from 1.25 to the current version vgmodify no longer allows moving of the VGRA to the end of the disk (VGRA relocation) or stealing PEs from the end of the disk. However stealing PEs from the start of the disk has been reinstated. It is planned to allow VGRA relocation and stealing PEs from the end of the disk with a future version of vgmodify, once extra testing has taken place. The first versions made available more widely will not permit VGRA relocation.

[James R. Ferguson]

Hi:

'vgmodify' is part of the standard LVM binary distribution as of 11iv3 (11.31).

The 11.31 manpages offer a nice discussion.

Regards!

...JRF...

[KathyL1]

It is now possible to do this using the vgmodify command which is available for HP-UX 11i V2 if you install the LVM patches PHCO_35524 and PHKL_36244.

Refer to the following Technical Knowledge Base document for specific information about the vgmodify command and Max PE per PV - http://www2.itrc.hp.com/service/cki/docDisplay.do?docLocale=en&docId=emr_na-c01007548-1


Kathy