currently I have a cluster of 3 hosts where each one has FC SAN connectivity to 4 LUNs: 3 are already configured as storage domains (1TB, 2TB, 4TB), one is free, not allocated.

See here for screenshot:

At the moment the command "multipath -l" run on hosts shows all the 4 LUNs.

Now I want to do 2 things at storage array level:

- remove the 2TB storage domain LUN

- remove the 20Gb LUN not yet allocated

What is the correct workflow, supposing I have already emptied the 2TB from VM disks ad such?

Select 2Tb SD, then Datacenter subtab, then "maintenance", detach" and at the end "remove"? 

I think I continue to see 4 LUNs at this point, correct?

Now I proceed with removal of lun at storage array level?

Should I select an SD line and then "Scan disks" to see refresh the SAN and see in multipath only 2 of them at the end?

Or any manual command at host level before removal from array?

Thanks in advance

Gianluca