Storage : Extending an existing FC based storage domain

Hi

I'm finding adding LUN's to an existing FC based storage domain a little erratic. Wondered if anyone else was experiencing similar.

So, we zone up some new luns to each of the hypervisor nodes in the a RHEV cluster. I then Edit the storage domain and my new luns appear as "Free".

I select one or more of the luns and hit OK.  I expect to see the storage domain extend in size but instead I get an error.

Error: Cannot extend Storage Domain. Storage device in unreachable from ${hostname}.

I suspect that one or more of the hypervisors in the cluster has not successfully "scanned" for the new LUN's. Sure enough, an inspection of multipath output shows that one (or more) of the hypervisors is not reporting on the newly added LUNs.

A manual rescan of the HBA's or a reboot of those hypervisors is required for them to successfully report the new LUNs.

We are then able to extend the storage domain.

Thanks