Patent ID: 7958273

Claim:
A system comprising: a first storage subsystem comprising: a first redundant array of independent disks (RAID) controller; and a first edge expander device, said first expander device communicatively coupled to said first RAID controller and further comprising a single subtractive port and a table mapped port; a first enclosure, said first enclosure housing said first redundant array of independent disks (RAID) controller and said first edge expander device; a second storage subsystem comprising: a second redundant array of independent disks (RAID) controller; and a second edge expander device, said second expander device communicatively coupled to said second RAID controller and further comprising a single subtractive port and a table mapped port; a second enclosure, said second enclosure housing said second redundant array of independent disks (RAID) controller and said second edge expander device; a first communication link coupling said single subtractive port of said first edge expander device to said table mapped port of said second edge expander device; and a second communication link coupling said single subtractive port of said second edge expander device to said table mapped port of said first edge expander device.