I have to add a new host to the production VI3 with shared LUNs on a Clariion storage.
Only a san rescan is required to get the production Datastores ? Of course, san zoning and lun mapping before.
Yes, assuming the zoning and LUN IDs are correct, you'll go to storage adapters and click on Rescan. Then scan for new devices and new VMFS volumes. If the data store does not appear, but you can see the LUN, then check /var/log/vmkernel for warning that include "snapshot". In that case the LUN IDs are not correct.