To increase a disk size for a VM

To increase a disk size for a VM:

1. In XenCenter "Storage" tab add a space
2. In the VM console create a physical volume: pvcreate /dev/xvdb
3. Extend a Volume Group for the physical volume: vgextend VolGroup00 /dev/xvdb
4. Extend a logical volume for the size of new disk: lvextend -L +39G /dev/VolGroup00/LogVol00
5. Switch to single user mode: init 1
6. Extend file system to the whole logical volume: resize2fs /dev/VolGroup00/LovVol00