Recently i’ve been doing some playing around with nested ESXi images for our upcoming Nimble Storage dHCI product launch. And I kept running into the same problem – nested ESXi hosts weren’t able to view and attach to iSCSI storage.
After some diagnosis, I found that nested ESXi hosts and iSCSI were failing on iSCSI Discovery. A quick view in the Storage Adapters screen showed that the Discovery IPs were configured correctly (my example has dual iSCSI subnets for best practice), but it was still failing.
Cut to the chase: turns out that you need to enable Promiscuous Mode on the vSwitch that you’ve configured your nested iSCSI environment to reside on.
Once this was configured, et-voila; volumes discovered happily by the nested ESXi hosts.
Hope this helps you!