To set the default Storage Repository (SR) in XenServer:
- Bring up the console
- Find the UUID of the pool
- xe pool-list
- Set the default SR
- xe pool-param-set uuid=<pool-uuid> default-SR=<sr-uuid>
You can also right click on the Storage in XenCenter and select Set as Default.
In either case, this is helpful if your default SR is the smallest disk on the server, and you are doing P2V operations.