Vg extend

[kamal_9]

Hi All
In vgdisplay -v iam getting the following output
VG Name /dev/vgbs
VG Write Access read/write
VG Status available
Max LV 255
Cur LV 4
Open LV 4
Max PV 16
Cur PV 2
Act PV 2
Max PE per PV 1279
VGDA 4
PE Size (Mbytes) 8
Total PE 2558
Alloc PE 1876
Free PE 682
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0

It means i can use upto 10gb of pv only .Now i want to add a lun of 15gb to that same vg will it create any problem .I hope ican use only 10gb of space in that 15gb lun .Will it give any errors ,if it gives any errors how to overcome that error
Thanks
Kamal

[Ravi_8]

Hi Kamal

your disk size is 20GB (Total PE * PE size).

so you can plug in the 15GB disk and extend the VG

[kamal_9]

Hi Ravi
which one we hav to consider Total PE or Max PE Per Pv value .
It will be good if u can tell me in brief about the value in the output
Thanks
Kamal

[Thierry Poels_1]

hi,

Ravi misread the vgdisplay output:
MAX PE per PV=1279
*
PE Size = 8
equals 10GB

If you add larger disks than 10GB you will be able to allocate 10GB without any problem.
To overcome this limit you can recreate the Volume Group or create a new volume group for the new disk.

regards,
Thierry.

[Thierry Poels_1]

"Total PE" = sum of all physical extents in the Volume group, thus of all included disks together.

Thierry.

[kamal_9]

Hi Thierry.

I dont want to create a newvg i want to extend this vg .will it create any problem while extending other than i can use upto 10gb of space.if it gives any errors how to overcome that error
thanks
kamal

[Thierry Poels_1]

hi,

If you add larger disks than 10GB in that volume group you will be able to allocate 10GB without any problem.

If I recall correct you will get a warning that you can not use the whole disk, but I should work without any problem.

regards,
Thierry Poels.

[Sunil Sharma_1]

Hi Kamal,

You can use upto 10gb of any LUN in this VG without any problem. It will not give any errore.

Sunil

[kamal_9]

Hi all
Thanks This what i want to confirm
If i want to change the Max PE Per Pv .how to do that iam having online JFS .is it possible to change that
Thanks
kamal

[Thierry Poels_1]

Hi,

you can only change "Max PE per PV" by recreating the VG, no other option.

regards,
Thierry.

[Ravi_8]

Hi kamal

sorry, i was in middle of a clearcase problem, hence miscalculated the disk size.

since your disk is 10GB in size, hence system allows you to use only 10GB of the 15GB disk.
The solution is ignite
make a make_tape_recovery of the existing VG (disk), plug in the new 15GB disk and restore on 15GB disk (by booting thru tape).
Now 15GB disk will be your default boot disk
Once you boot with 15GB disk
#pvcraete -f /dev/rdsk/<10GB disk>
#vgextend vg00 /dev/dsk/<10GB disk>

[kamal_9]

hi Ravi
but thsi not a root vg

[Sunil Sharma_1]

Kamal,

You can not change "Max PE per PV". This value can be configured only at the time of VG creation.

The best and safest way is to backup your data on vgbs volume group and the remove old VG the create new VG with higher number of PE.

Sunil

[Ravi_8]

Hi,

Since the disk is not root vg, i also propose Sunil sharma's suggestion.

[kamal_9]

Hi All
Wish You A very Happy NewYear
Yesterday I as per my earlier inputs . I added one 15 gb lun to that vg .and its increases the FREE PE value also .Now after doing vgextend by vgdisplay -v shows
# vgdisplay -v /dev/vgbs |pg
--- Volume groups ---
VG Name /dev/vgbs
VG Write Access read/write
VG Status available
Max LV 255
Cur LV 4
Open LV 4
Max PV 16
Cur PV 3
Act PV 3
Max PE per PV 1279
VGDA 6
PE Size (Mbytes) 8
Total PE 3837
Alloc PE 2546
Free PE 1291
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0
but Iam facing problem while doing lvextend .if i give
#lvextend -L 12288 /dev/vgbc/lvbahtmp
it says
lvextend: not enough free physical extends available
logical volume /dev/vgbc/lvbahtmp could not be extended balonging to vgbc /dev/vgbc
Failure caused by strict allocation policy
can u tell me what it means.How to overcome from this