On a new XenServer deployment EXT storage is default. Although EXT is nice (ability to manipulate raw VHD files and use sparse storage), LVM is faster and more stable. Here is how to switch between storage modes (be sure to back up all data first, as this will wipe everything in the repo):
Use ‘xe sr-list’ and ‘xe pbd-list’ to find your local storage SR and it’s PBD. Also note the physical device number / partition in the PBD, so you can re-create it on the same device later on.
Unplug the active SR’s PBD (physical block device):
xe pbd-unplug uuid=<pbd_uuid>
Destroy the SR:
xe sr-destroy uuid=<sr_uuid>
Create a new SR of the specified type and location:
xe sr-create content-type=user device-config:device=/dev/<device> host-uuid=<host_uuid> name-label="Local Storage" shared=false type=<lvm|ext>
You can verify the SR again with ‘xe sr-list’ and it should already be in XenCenter as the default.