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Monitoring the Cooling Fans in a Junos Space Appliance


For optimal cooling of the Junos Space appliance, verify the condition of the fans.


Monitor the status of the fans. The cooling fans work in unison to cool the appliance components. An alarm is triggered when a fan fails and the Hardware Fault LED on the appliance front panel starts blinking. When one fan fails, the remaining fan begins to run at full speed.

To monitor the fans, do the following:

  1. Log in to the appliance as the admin user.

    The Junos Space Settings Menu appears.

  2. Type 6, which is the (Debug) run shell option.

    You are prompted to enter your password.

  3. Type the password for the admin user and press Enter.

    You are taken to the shell.

  4. To view the status of the cooling fans, execute the following command:


    The Junos Space installer automatically sets up the Linux-monitoring sensors (lm_sensors) and configures lm_sensors to run at startup.

Sample Output



The output of the sensors command provides information about the fan speeds and whether an alarm has been triggered. In the output, fans 3 and 4 represent the two rear chassis fans. The speed of the fans (in revolutions per minute [RPM]) and an indication of an alarm, if any, are displayed.