extending physikal disk size

[Claudiu Schmidt]

Hi,

i have a eva disk array for testing on an HPUX 11.00 and 11.11 server. On the EVA, it is possible to increase the size of a lun on the fly.how can i make lvm to see this extra space. What i found out till now , is that diskinfo shows the old size, as long as the volume group is active. deactivating volumegroup, shows the new lunsize. but still, the pvdisplay shows old value. is there any command for updating the number of pvextends?

Rgds,

Claudiu

[Michael Tully · Accepted solution]

Sorry, but once you have set up a volume group with a disk you cannot extend that volume to a bigger disk size.
You would need to remove the disk from the volume, and then add it in again, providing it does not exceed the size of the first disk in the volume group. If it did you would only get the equivalent of that disk, no more.
Assuming it does not, e.g.:

# vgreduce /myvg /dev/dsk/cxtydz
do your changes to our disk
# ioscan -fn
# insf -e
# vgextend /myvg /dev/dsk/cxtydz

[Stefan Farrelly]

If diskinfo doesnt show the new size then the size of the disk/lun has NOT increased. Whatever you did on your disk array to increase the size of the disk/lun did not work. Did you try a reboot to see if that prompted diskinfo to detect the new size ?

The first step is to get diskinfo to report the correct size (fix it on your array), then you will have to re-pvcreate your disk (as pointed out previously, vgremove it, pvcreate it, vgextend it).

[Claudiu Schmidt]

well, i did some more testing, and here are the results:
increasing the size of the lun online on the eva while the volumegroup is still active will show only the old size in diskinfo.
after vgchange -a n volgrp,diskinfo will show the new size.
a pvcreate on the physical volume will use all of the new space, but all the data will be lost.