M320 Router, T320 Router, and T640 Routing Node Redundant Host Subsystems
On the M320 router, T320 router, and the T640 routing node, the host subsystem consists of a Routing Engine and Control Board functioning as a unit. Two host subsystems can be installed in each routing platform. One pair functions as master, while the other stands by as backup should the master Routing Engine fail. (See Figure 186, Redundancy Connection for an M320 Router, and Redundancy Connection for a T320 Router and T640 Routing Node.)
