topic Re: extending max_pe in Operating System - HP-UX

extending max_pe

bassey essien_1 — Mon, 08 Jan 2001 18:06:15 GMT

I want to change the max_pe on a volume to some
larger number in other to accomodate the new
60 Gig disk. the default number was set at 1060 mb on an 8 gig disk. when i ran vgextend on older volume group, i could only get a minimal disk space increase, much of space on new disk still remains unclaimed. How do i change max_pe on an existing volume group.
thanks.

Re: extending max_pe

Bruce Regittko_1 — Thu, 18 Jan 2001 04:07:30 GMT

Hi,

It is great to finally be able to read your posts!

Unfortunately, the maximum physical extents per physical volume can only be set at volume group creation with the vgcreate command. Whenever I create a new vg, I always try to anticipate what the largest disk I will add to it and set max_pe accordingly.

--Bruce

Re: extending max_pe

Darrel Louis — Thu, 18 Jan 2001 14:23:45 GMT

Bassey,

The maximum number of physical extents allowed per physical volume is 65,535. (Range is 1 - 65,535; Default is 1016; set using vgcreate -e)

When you're trying to add a disk to a VG and it's out of pe. The only way to proceed.
- Make a good backup
- Create a new VG with enough pe(vgcreate -e #####)
- Copy the data to new VG.

So, you need to create a new volume group.

Regards

Darrel

Re: extending max_pe

Dave Wherry — Thu, 18 Jan 2001 17:48:32 GMT

As the others said, it can only be changed when you create the volume group.
At the risk of sounding too obvious, if you do not care what your volume group number is and your data is on file systems, not raw, you can save a lot of time.
Create a new volume group with the new disk and new logical volumes.
Create and mount new file systems. Say you have a file system named /data in your old volume group. Create /data2 in the new.
Simply copy your data from the old to the new.
Unmount both and remount the new as /data. Edit /etc/fstab to reflect the changes.

There's nothing special about this. It just saves you the backup and restore time. Copying from disk to disk is much faster.