VG extend without unmounting VG when JFS is installed

[rana786]

Hi All,

I need to increase a Volume group where storage space (EMC) is unavailable. So we are adding one LUN to the system to increase the space. In this case I need to increase the Volume group first. JFS is installed in this system. Is it possible to extend the Volume group without unmounting the all logical volume of this volume group? What would be the normal practice of doing this?

Rgds,
Rana

[Darrel Louis · Accepted solution]

Hi,

First you need to prepare the new disk:
- pvcreate /dev/rdsk/c?t?d?

Extend the Volume Group
- vgextend /dev/ /dev/dsk/c?t?d?

If you have Online JFS:
- lvextend -L /dev//
- fsadm -b /mountpoint

Example: Extend /test to 500Mb
lvextend -L 500 /dev/vg00/lvtest
fsadm -b 512000 /test

Darrel

[Steven E. Protter]

Shalom Rana,

The code provided is correct.

The normal practice is to do this when the system is running, without umounting.

If we had the time, I'm sure most systems administrators would prefer to back up the filesystem and do it the old way. Online JFS provides us the ability to re-size on the fly.

As far as the EMC goes, you can't increase a filesystem that is hosted on the EMC while its offline. That is beyond the capabilities of even Online JFS.

SEP

[eran maor]

Hi Rana

you will need to check if you had install the onlinejfs . jfs install itself doesnt give you the option of -b in the command fsadm .

without this product you will need to umount your file system .
the easy way to check if you have onlinejfs is simple to try to do the command fsadm -b
if it will give you an answer that this optino is not supported , it mean - no onlinejfs .

cheers

eran maor

[eran maor]

Hi Rana

you will need to check if you had install the onlinejfs . jfs install itself doesnt give you the option of -b in the command fsadm .

without this product you will need to umount your file system .
the easy way to check if you have onlinejfs is simple to try to do the command fsadm -b
if it will give you an answer that this option is not supported , it mean - no onlinejfs .

cheers

eran maor