Max PE per PV

[rolando diaz_1]

Hi:
I have a D280 and the vg00 have
Max PE per PV = 2000

I want to do a vgextend with a new
drive disk .

I obtain the next message:
" vgextend Not enough physical extents per
physical volume
Need 2190,have 2000 "

How I can to increase this, without
to lose the information of vg00

Thank
Rolando

[Michael Tully]

If the drive is of bigger size, you will
be limited to the size of the first disk
in the volume group. This unfortunately
is the way that this is designed. You will
need to either create another volume group
or build a second root volume group and
once you have successfully booted off this
you can trash to the original disk and
include it.

[Michael Tully]

One thing you could look at is to create
a make recovery tape and build your second
root group from this. Heres a procedure
you could use:

Create an ignite tape
# make_tape_recovery -x inc_entire=vg00 -I -v -a /dev/rmt/0mn

Boot your server from this tape and use the
second disk in which you can create a
secondary boot partition. Once you can
successfully boot from this, trash your second
disk and include in this new vg00 volume.

[Arockia Jegan]

Mic has given you the perfect solution. Whenever you create a volume group make sure you are setting up the proper value for max_pe. Other wise you will end up with this kind of problem when you want to add the physical volume that size is bigger than the PV that was first used when you create the volume group,

If you don't define this max_pe value(when you create VG)manually it's going to be setup by the LVM automatically. LVM is going to calculate this value from the PV that's added to the VG when you create the VG.

The same way you should be careful about the PE size(Physical extents size).

[PIYUSH D. PATEL]

Hi,

The physical extent sent is defined while creating the volume group. Hence whenever you add a new hdd the max no. of PE depends upon the PE size which is defined for the original hdd which is already configured in your system.

Hence your new disk will be limited to the PE according to the PE size defined for the VG.

Hence the method suggested by Mic is right. Or else you will have to copy all your data and recreate the VG with the new PE size and restore back the data.

Piyush

[Wodisch_1]

Hi Rolando,

all the others are correct, of course - bad luck for you :-(

But if you go for the "Ignite/UX" way to re-install your HP-UX with *better* parameters, do NOT simply increase the MaxPEperPV parameter, but increase the PEsize parameter, say, to 32MB.
Then you can use (only) 1024 PEs per PV, but you will be able to use 32GB disks!
The same is especially true for data VGs: increase the maxPVperVG and the PEsize, but reduce the maxLVperVG (who needs 255 LV per VG?) and the maxPEperPV (1024 PEs of 64MB permit up to 64GB, after all).
Remember that the whole VG-information has to fit into a single PE, and there is an upper limit of 65535 PEs.
So in my experience it is reasonable to use as small headers as possible...

Just my $0.02,
Wodisch

[Sanjay_6]

Hi Rolando,

Maybe this can help you understand the problem,

http://support2.itrc.hp.com/service/cki/docDisplay.do?docLocale=en_US&docId=200000058668847

The doc id is KBRC00001020

Hope this helps.

Regds