Please see this original post for information on a vSphere 4 storage bug that appears to be getting several people.
It deals with removing a LUN from the server…and the order you perform the process. The proper sequence is:
- In the vSphere client, vacate the VMs from the datastore being removed (migrate or Storage vMotion)
- In the vSphere client, remove the Datastore
- In the vSphere client, remove the storage device
- Only then, in your array management tool remove the LUN from the host.
- In the vSphere client, rescan the bus.