topic Re: Total PE modification in Operating System - HP-UX

Total PE modification

System Unix — Sun, 08 Jan 2006 10:48:23 GMT

Hi,
The storages software allow expansion of luns on the fly, but from the host side, if the disk (lun) is in a volume group, the total PE will not change as a result of lun expansion.
is there a way to modify this value in with adb ?

thanks
Reuven

Re: Total PE modification

melvyn burnard — Sun, 08 Jan 2006 11:52:23 GMT

To modify the VG attributes, you can log a call with your local HP Response Centre and request the unsupported utility called vgmodify if you are on HP-UX 11.11

Re: Total PE modification

Doug O'Leary — Sun, 08 Jan 2006 13:00:12 GMT

Hey;

Normally, no, the total pe is set at boot time. Unless you use the vgmodify utility referenced in the previous post, you will have to back everything up, destroy the vg, recreate and and restore the data.

I've taken to setting the total pe upon vg creation using the -e switch to vgcreate. If you set it to something significantly larger than what you need currently, you'll be able to add larger disks to the vg later.

The question then becomes what to set it to. You'll have to play with the math. The forumla is:

${biggest_disk} = ${total_pe} * ${pe_size}

My client is currently using 33.72 gig EMC metas which would normally result in a total_pe of about 4317 w/pe size of 8megs. I've been up'ing that to 10,000 which means I could add a disk up to 78 gigs.

I know that won't help for your current problem, but if you start doing this, you'll avoid the problem in the future...

Doug

Re: Total PE modification

Sivakumar TS — Sun, 08 Jan 2006 21:52:24 GMT

Hi,

Though the LUN has been extended, for LVM to recognise that you should use

#lvextend amd extend the filesystem.

And use #fsadm to extend the filesystem ONLINE ( if you have Online JFS )

otherwise you can use unmount and use #extendfs

With Regards,

Siva.

Re: Total PE modification

Hoang Chi Cong_1 — Sun, 08 Jan 2006 22:49:36 GMT

Hi

Check this link:
http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=987360

The Max PE per PV is define when you create VG.
You need get support from HP if you want to modify it.

Goodluck!
Hoang Chi Cong

Re: Total PE modification

System Unix — Mon, 09 Jan 2006 02:25:20 GMT

Thanks very much for your quick reply and assistance.
I have tried the vgmodify as was suggested by Melvyn Burnard and it works.( thanks )
I have tried it on 11.11, and on 11.23 Itanium SD64A model.