We currently support the addition of no more than one SAS-Connected Expansion Chassis per ActiveRAID.
Adding an expansion chassis is a great way to save Fibre Channel ports and add
more disk to the two controllers, and still allow the option to have one globally sparing drive all 32 disks.
While we (and our competitors) certainly have the capability to 'chain' more expansion chassis's - we are
concerned that when we extend the SAS chain beyond one expansion system a failure of a drive or
expansion system controller could lead to significantly diminished speed or require taking down the entire
array to replace a failed component. For this reason, and for the best user experience we officially
support a maximum of one expansion chassis per ActiveRAID.