HP MSA Expansion Cabinet Setup
Shutdown storage controllers and power-off the existing MSA.
Connect the SAS cables to the output ports on the existing MSA and to the input ports (on the left if you’re looking at the back of the unit) on the expansion cabinet. (Remember to remove the tiny plastic tabs from both ends of the cables!).
Power on the EXPANSION unit first! Wait for a couple of minutes for the controllers to init.
Power on the MSA. Wait for the storage controllers to boot. Log into the web interface. You should see the new enclosure listed in the tree view. (the LED display on the expansion unit will change to “2” when it’s detected)
Create a new RAID-10 virtual disk with hot spare, using the disks in the expansion unit.
Create new volumes (and tick the “Map” box to assign LUNs) to fill the virtual disk (VMware can’t support volumes larger than 2TB).
Power-on the hosts. Rescan storage controllers to locate the new LUNs.
Go to Configuration -> Storage and Add Storage. It will detect the new LUNs and you can create datastores on each.