JUNOS Internet Software Network Operations Guide: Hardware
262 ! Understanding the Cooling System
Figure 115: M320 Router Cooling System and Airflow
The host subsystem monitors the temperature of the router components. When the
router is operating normally, the fans function at lower than full speed. If a fan fails
or the ambient temperature rises above a threshold, the speed of the remaining
fans is automatically adjusted to keep the temperature within the acceptable range.
If the ambient maximum temperature specification is exceeded and the system
cannot be adequately cooled, the Routing Engine shuts down some or all of the
hardware components.
M320
router rear
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Air filter
Fan tray
Air intake
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Air exhaust
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Air filter