1. Open the console of your XenServer Resource Pool Master.
2. Run xe sr-list

        That sould give you some detailed information about your repos:

          uuid ( RO)                : abcdefgh-e007-792d-37ae-414ffd62f67c
          name-label ( RW): d_poisson
          name-description ( RW): Hardware HBA SR [HP - /dev/sdb [sdc]]
          host ( RO): hostname.domain.local
          type ( RO): lvmohba
          content-type ( RO):

      Or type xe sr-list name-label=<Your_SR_Name> for only the specified information.

   3. Find the UUID associated with the name of the SR you wish to resize. Make note of the UUID.

   4. Next, find the device name. To do this, run pvscan | grep <uuid> - The device name will look like /dev/sdb – Make note of this as well.

   5. Run pvresize <devname>

   6. Run xe sr-scan <uuid>

   7. Verify that the Storage Repository shows up with the right size in XenCenter.