Yes - as I said, I've got all three oVirt Hosts talking to all three Ceph iSCSI Gateways, and can see all four LUNs (via each of the three Gateways). Just to be 100% clear: yes, this means that all three oVirt Hosts are logged into the Ceph Cluster (via all three of the iSCSI Gateways). Yes, I believe that the way it works (but *please* do not take this as gospel) is that each iSCSI Gateway - and it is recommended that a Ceph Cluster have 2-4 of them) - plays the part of of the Target ie there is one Target with each of the 3 Gateways as "subordinate", as are the four LUNs and the three oVirt Initiators, which in turn show each LUN as subordinate to them, as well. Very confusing on initial look-see, but it sort of makes sense, I suppose. However, please see my next/other post in this thread - and thanks for the help.