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M120 Host Subsystem Description


The host subsystem provides the routing and system management functions of the router. You can install one or two host subsystems on the router. Each host subsystem functions as a unit; the Routing Engine must be installed directly into the Control Board.


We recommend you install two host subsystems for redundant protection. If you install only one host subsystem, we recommend you install it in slot CB0.

Each host subsystem has three LEDs that display its status. The host subsystem LEDs are located in the middle of the craft interface. For more information about the host subsystem LEDs, see Host Subsystem LEDs on the M120 Craft Interface.

The host subsystem consists of the following components: