Encrease vg size

[Igor Sovin]

I had vg with 100 Gb disk belongig to it.
Disk was presented from EVA 5000. Then I decided to encrease Vdisk size, on Eva 5000, to 150 Gb.
I do umount to all filesystems on vg.
What should I do with vg so I can see size 150 Gb (in Total PE size) in the vgdisplay output?

[Luk Vandenbussche · Accepted solution]

Igor,
You can't increase an lun on hpux, you had to create an additional lun which you can add to your vg. I think you have a big problem now. You should recreate your VG and restore your data now

[Igor Sovin]

Hm..
thank you

[Doug O'Leary]

Hey;

I'm not sure you'll need to restore your data; however, you definitely won't see the extra storage.

If you had to reformat the lun in order to extend it, then your data is toast. Otherwise, it should still be there.

The problem with your approach is the same problem that exists if you try to add a disk that's significantly larger than the one used to create the volume group.

When creating vgs, the system figures out how many physical extents are needed to use the entire drive and sets that as the maximum PE per PV. That's one of the few parameters that you can't change after the VG has been created.

So, in order to see the entire 150 gigs of LUN, you'll need to:

1. Back up all your data
2. Unmount everything.
3. vgremove ${vg} to eliminate the vg.
4. Recreate the vg
5. Recreate the LVs
6. Restore your data.

HTH;

Doug

[Cem Tugrul]

Igor,

Believe me i did it many times before...
Hp does not recommend such kind of increasing
:-(
so everytime you have to;
1- backup your data
2- only umount FS which refers VG that you want to increase
3-delete LUN from EVA which refers VG that you want to increase
4-spmgr delete Cxtydz (which refers your old LUN)
5-creat new LUN(150Gb) and present to your Host
5-VG create
6-FS create
7-mount it
8-restore your data

That's the steps...

Good Luck,

[Steven E. Protter]

You can not make a Volume group bigger or change any parametrs after its built. You can add disks with vgextend if the volume group can accomodate the extra PE's.

Tip: when you build a volume group use the -p physical volumes parameter. Set it higher than you will ever need and then available PE's will be concentrated, allowing for greater capacity on fewer drives.

The default PE distribution, for lack of a better term is over 255 disks. How many people actually have that many disks in a volume group?

SEP

[Devender Khatana]

Hi,

As posted above by others it is not possible to extend the size of a disk occupied by a volume group. However adding another disk of same or less capacity then existing disk/LUN capacity will be supported by default.

If you intend to add a higher capacity disk to a VG then the one which is the biggest one of those on which VG was initially created, you should check two parameters in your existing VG. First is MAX_PE_PER_PV and second is PE_Size. If these two were not set properly while creating VG, will be set to adjust to maximum size of the physical volume while creating the VG. Therefore not allowing to allow addressing full space in the higher capacity disks added later.

For ex. if you created VG on a 100GB LUN and used PE Size of 8MB, the MAX_PE_PER_PV for that VG will be set to approx. 12800. In future if you add a LUN of 150GB to that VG, your VG can only use 100GB of that space.

To avoid such scenario you should define either PE_Size to 16MB with and MAX_PE_PER_PV to approximate same value. Or should define MAX_PE_PER_PV to a higher value.

HTH,
Devender

[Nguyen Anh Tien]

You have 2 solutions:
SOL1:
Backup all data on vg that (100GB belong to
Delete all lv on that vg and pv
Create LUN 150GB and add to that vg
lv create and restore date
SOL2:
create one more LUN (size 50GB)
Extend it to that vg
lvextend and fsextend if need.
That's all
YOU CAN NOT extend LUN for HPUX
HTH
PS: pls assign point for us