Mx204 Component Redundancy - Juniper MX204 Hardware Manual

Figure 5: ESD Points on the MX204 Router
Front panel
1
1 ESD points
—

MX204 Component Redundancy

A fully configured router is designed so that at no single point of failure can cause the entire system to
fail. Only a fully configured router provides complete redundancy. All other configurations provide partial
redundancy. The following major hardware components are redundant:
Power supplies—The router supports two power supply modules. The MX204 router provides 1+1
redundancy for the system. Both AC and DC systems can withstand the failure of a single power supply
without system interruption in 1+1 redundancy mode. If one power supply fails in a fully redundant
system, the other power supply can provide full power to the router indefinitely.
Cooling system—The cooling system has a total of three fan modules, which are controlled and monitored
by the host subsystem. A fully configured router needs all the fan modules to operate normal. The fan
modules are at the rear and are used to cool the router. If a fan fails or the temperature of the chassis
rises above the temperature threshold, the speed of the remaining fans is automatically adjusted to keep
the temperature within the acceptable range.
CAUTION:
supply modules must be operational, and in the event of any module failure the failed
module must be replaced immediately.
SEE ALSO
Locating the Serial Number on an MX204 Router or Component | 139
Guidelines for Packing Hardware Components for Shipment | 142
Returning a Hardware Component to Juniper Networks, Inc.
Rear panel
For a fully configured router, all the three fan modules and the two power
1
25