no avaialbe disk shown up

Hi All,

We have one hyper-v cluster with three Windows 2008 SP2 servers.  We have a SAN storage.  We presented one LUN with size 900GB to these three host servers.  They all can see the 900 GB disk and I brought online and created volume.

Now, I tried to add the disk to the cluster.  When I click "Add Disk", the 900 Gb disk is not shown up.

How should I be able to add this disk to the cluster storage?

Thank you.