Dell PowerVault MD1120 Hardware Owner's Manual page 23

port on the primary EMM will control physical disks in slots 12
through 23; the server or controller port attached to the In port on the
secondary EMM will control physical disks in slots 0 through 11.
NOTE:
In split mode, you can cable the enclosure to operate in either a two-
host or single-host configuration. In single-host configuration, you can cable
both EMMs to either the same host controller, or to a separate host controller.
Figure 2-1. Single Host Server, Unified Mode (No Expansion)
Figure 2-2. Single Host Server, Split Mode (Expansion Not Supported)
Figure 2-3. Two Host Servers, Split Mode (Expansion Not Supported)
Operating Your Storage Enclosure
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