JoJoGabor
Expert
Expert

Check for any differences in hardware between the hosts, in particular the HBAs, their firmware version and/or NICs if you are using iSCSI and their firmware versions. Then check all this hardware in on the Hardware COmpatibilty List for ESX 4

Double check the LUN presentation on the SAN also and verify the WWIDs of the HBAs match up to what is in the SAN