Juniper MX10008 Hardware Manual page 48

Figure 22: Fan Controller JNP10008-FTC2
The system continually monitors the temperature of critical parts across the chassis and adjusts the chassis
fan speed according to the temperature.
Software controls the fan speed. Under normal operating conditions, the fans in the fan tray run at less
than full speed.If one fan tray controller fails or appears missing (such as when an SFB is being replaced)
the other fan tray controller sets the fans to full speed. This allows the router to continue to operate
normally as long as the remaining fans cool the chassis sufficiently. Use the show chassis fan command
to see the status of individual fans and fan speed. Here is an example of output from JNP10008-FAN and
JNP10008-FAN-CTRL:
user@host> show chassis fan
Item
Fan Tray 0 Fan 0
Fan Tray 0 Fan 1
Fan Tray 0 Fan 2
Fan Tray 0 Fan 3
Fan Tray 0 Fan 4
Fan Tray 0 Fan 5
Fan Tray 0 Fan 6
Fan Tray 0 Fan 7
Fan Tray 0 Fan 8
Fan Tray 0 Fan 9
Fan Tray 0 Fan 10
Fan Tray 1 Fan 0
Fan Tray 1 Fan 1
Fan Tray 1 Fan 2
Fan Tray 1 Fan 3
Fan Tray 1 Fan 4
Fan Tray 1 Fan 5
Fan Tray 1 Fan 6
Fan Tray 1 Fan 7
Fan Tray 1 Fan 8
Fan Tray 1 Fan 9
Fan Tray 1 Fan 10
Status RPM
OK 9750 Spinning at normal speed
OK 9600 Spinning at normal speed
OK 9750 Spinning at normal speed
OK 9750 Spinning at normal speed
OK 9600 Spinning at normal speed
OK 9750 Spinning at normal speed
OK 9750 Spinning at normal speed
OK 9600 Spinning at normal speed
OK 9600 Spinning at normal speed
OK 9750 Spinning at normal speed
OK 9750 Spinning at normal speed
OK 9750 Spinning at normal speed
OK 9600 Spinning at normal speed
OK 9600 Spinning at normal speed
OK 9750 Spinning at normal speed
OK 9750 Spinning at normal speed
OK 9750 Spinning at normal speed
OK 9750 Spinning at normal speed
OK 9750 Spinning at normal speed
OK 9600 Spinning at normal speed
OK 9750 Spinning at normal speed
OK 9450 Spinning at normal speed
Measurement
49