Unable to extent the physical volume

[amsethi]

Patrick

Even I would like know how to extend the physical volume of a disk which is part of a existing volume group when the LUN size is increased on the storage side .

Amit

[Senthil Kumar .A_1]

Hi,

Can you elaborate on "Internal Feature" a little more please...

As far as increasing the size of the existing lun from storage side is concerned, the answer is the LVM will not identify the new size. You might have to recreate the VG with the Luns to make the LVM realize the actual size of PV. One other issue, while creating a VG, always make sure the first PV added to a VG is the largest among the group of PV's you wish to add. For example, if you have 2 and 3GB disk. If you happen to add 2GB first, the VG when created will calculate the "Number of PE's" per VG and hardlock it. Later when you add the 3 GB disk only 2 Gb of it will be recognized. Meaning you need to trash the VG and recreate it again to rectify the situation. Though the order of PV addition, I'm not too sure. I will wait for experienced Admins to reaffirm my point.

SK

[amsethi]

Sorry Senthil I can't disclose the feature. Hope everybody understands.

But I can tell you one thing that I used all the space of my older physical disks i.e 2GB each and then migrated it to a new set of physical disks each having 3GB size.

[Vivek_Pendse]

there is a limitation in PE for existing vg.
you will need to take backup of existing vg & restore it on new created vg.
while creating vg; mention pe_size more than the existing..
e.g.
# vgcreate -s 16 PV_NAME

Thanks,
Vivek

[amsethi]

Vivek

I did vgcfgbackup and vgcfgrestore but the with "vgcreate -s 16 pv_path" but still the physical disk size does not changed.

Amit

[Senthil Kumar .A_1]

Hi,

What vivek meant was not vgcfgbackup and vgvfgrestore, he meant the backup of data on LV's for the VG, delete the existing VG, recreate them and restore teh data.

Anyway for whats worth it, looks like from HPUX 11iv3(11.31) onwards, there seems to be a command by name "vgmodify" that lets you change the parameters registered in VGRA. I'm not too sure this would remediate your situation. Also a word of mouth, there is an unsupported version of vgmodify for 11.11. May be you can try it.

SK

[KathyL1]

The vgmodify command which is available for HP-UX 11i V2 if you install the LVM patches PHCO_35524 and PHKL_36244.

Refer to the following Technical Knowledge Base document for specific information about the vgmodify command and Max PE per PV - http://www2.itrc.hp.com/service/cki/docDisplay.do?docLocale=en&docId=emr_na-c0
1007548-1


Kathy