Xen Guest - Disk Extending

Adding Disk on Xen Guest:


To resize the disk space of a xen DomU that is using Logical Volume Manager(LVM) is very easy. Below is step by step on how to do the resizing process.

1. Create a new image with the size that you require. Just give any meaningful name to the image. In this case I will use the name extended.img
# dd if=/dev/zero of=extended.img bs=1 count=1 seek=20G conv=notrunc
2. Add the new image to the configuration file of your DomU. In this example, the name of the domU is xen0
# vi /etc/xen/xen0
Add these line to it disk = [ 'tap:aio:/path/to/xen/xen0.img,xvda,w','file:/path/to/xen/extended.img,xvdb,w' ]
Save
3. Start your domU
# xm create xen0
4. Access your domU
# xm console xen0
5. Once inside, check whether the new image is detected
# fdisk -lu
6. After confirm that your new hard disk image is detected, it is time we have to work on the lvm
Create new physical volume (PV) using the new hard disk image
# pvcreate -v /dev/xvdb
Check that you have successfully added the PV
# pvdisplay
Extend your existing volume group (VG) to include the new PV
# vgextend -v VolGroup00 /dev/xvdb
Check that you have successfully add the PV into the VG
# vgdisplay
Extend your logical volume (LV)
# lvextend -L +20G -v /dev/VolGroup00/LogVol00
Check that the extension has been added
# lvdisplay
If all the steps are successfully done, you have to resize the / partition
# resize2fs /dev/mapper/VolGroup00-LogVol00
7. You are done. Check your new hard disk space :)
# df -lh