Extending logical Volume

[Hanwant Verma_1]

I have a one volume group named /usr2 in HP UX 11.11 whihc is 74% full. How can i extend this volumet group?

[Alex Lavrov.]

lvextend -L /dev/vgXX/lvolXX

fsadm -b /usr2

to modify FS online, you have OnlineJFS to be installed.


Alex.

[Alan Meyer_4]

without OnlineJFS, you'll need to unmount the filesystem to extend it.

[Hanwant Verma_1]

Can you tell me the exact process, step by step please.

[Alan Meyer_4]

# fuser /usr2

This will give you the processes which are accessing /usr2 and they will need to be shutdown.

Then
# bdf /usr2

Notice the first column which tells you the logical volume information

# umount /usr2

# lvextend -L /dev/vgXX/lvolXX

where /dev/vgXX/lvolXX matches the logical volume information retreived from the bdf.

# fsadm -b /usr2

# mount /dev/vgXX/lvolXX /usr2

Or if /usr2 is in the /etc/fstab file, you can issue a "mountall" command which will then do fsck on the new filesystem and also mount the filesystem with proper switches too.

[Alex Lavrov.]

Actually I did ....

If you want to do it without OnlineJFS:

lvextend -L /dev/vgXX/lvolXX
umount /usr2
extendfs /dev/vgXX/rlvolXX
mount /usr2


Done.

[john kingsley · Accepted solution]

identify the lvol associated with /usr2:
# bdf | grep usr2

Check to see how much free space there is in usr2's volume group:
# vgdisplay /dev/

extend logical volume:
# lvextend -L /dev//

Find out if you have OnlineJFS:
# swlist -l fileset | grep -i onlinejfs

With OnlineJFS:
# fsadm -b $((*1024)) /usr2

Without OnlineJFS:
- Stop all process accessing /usr2
# umount /usr2
# extendfs /dev//
# mount /usr2

[Alan Meyer_4]

oops my fsadm line should be;

extendfs /dev/vgXX/rlvolXX

[Hanwant Verma_1]

umount gives me the following error

umount: cannot unmount /usr2 : Device busy

[john kingsley]

You have to kill all of the process accessing /usr2.

Run:
fuser -cu /usr2

This will give you the list of processes using /usr2.

[Helen French]

If you have an active Database or files source/user data exists on this file systems, I wouldn't recommend unmounting the FS now. If there is no user interaction on this FS, you can safely unmount it. Also make sure that you are not in that directory (cd /).

I would also suggest having a fresh backup of the file system you are trying to change and make sure you have enough free PEs (vgdisplay -v vg_name) on the volume group. Btw, extending a volume group and logical volume is totally different. I guess you are talking about exteding your LV here.

[Hanwant Verma_1]

Can i restart the server in sigle user mode and then follow the process, to be at safer side?

[john kingsley]

If you have a lot of process running that use this filesystem, it would be a good idea to restart you system into single user mode to do this. That way, you're guarantee that everything comes down cleanly. In single user, your paths may not be set correctly, so you may have to run /sbin/extendfs

[Alan Meyer_4]

single user is always safer for these things...

[Helen French]

If you can reboot the server without any user interruptions, I would say that's the safe case. Once rebooted, you can mount the root volumes (mount -a) from vg00 and then try running the LV extend commands.

[Hanwant Verma_1]

Thanks everyone, i have extended the volume group in single user mode successfully.