We are migrating from Dell ESX VMWare 4 to Cisco UCS ESXi VMware 5 and been running into some horrendous results when trying to do say a storage vmotion with UCS or even just powering up a server on UCS that was unregistered from the old vCenter and now trying to bring into the new. Anyhow I wondered if an expert could help me understand this piece. Each ESXi in UCS have iSCSI initiator server locations in the Static Discovery tab. See attached. But it looks to me like the consultant put in both the IP addresses which should be reachable from the UCS/ESXi and the addresses which should only be accessible from the older ESX VMW4 environment. Is it possible this is what is causing problems when trying to access that data store? Under no circumstances should the UCS be able to reach any of the four 172.16.0.x addresses. It should only ever have access to the two 172.16.200.x addresses. Could it be that the more the UCS demands of iSCSI the more failures there will be because of the wrong addresses in there? Or would the ESXi hosts automagically know that it could not reach the 172.16.0.x addresses and not try to access those IP? Also there is configuration in the Dynamic Discovery tab which actually has the correct addresses there. Which takes precedence the Static Discovery or the Dynamic? I think I might have found an issue but perhaps it's just beginner-itis seeing a red herring?