Maintaining the M320 Fan Trays

Purpose

For optimum cooling, verify the condition of the fans.

Action

On a regular basis:

• Monitor the status of the fans. The fan trays each contain multiple fans that work in unison to cool the router components. If one fan fails, the host subsystem adjusts the speed of the remaining fans to maintain proper cooling. A red alarm is triggered when a fan fails, and a yellow alarm is triggered when a fan tray is removed.
• To display the status of the fans, issue the show chassis environment command. The output is similar to the following:
  user@host> show chassis environment

  Class Item                    Status  Measurement
  ...
  Fan   Top Left Front fan      OK      Spinning at normal speed
        Top Right Rear fan      OK      Spinning at normal speed
        Top Right Front fan     OK      Spinning at normal speed
        Top Left Rear fan       OK      Spinning at normal speed
        Bottom Left Front fan   OK      Spinning at normal speed
        Bottom Right Rear fan   OK      Spinning at normal speed
        Bottom Right Front fan  OK      Spinning at normal speed
        Bottom Left Rear fan    OK      Spinning at normal speed
        Rear Fan 1 (TOP)        OK      Spinning at normal speed
        Rear Fan 2              OK      Spinning at normal speed
        Rear Fan 3              OK      Spinning at normal speed
        Rear Fan 4              OK      Spinning at normal speed
        Rear Fan 5              OK      Spinning at normal speed
        Rear Fan 6              OK      Spinning at normal speed
        Rear Fan 7 (Bottom)     OK      Spinning at normal speed
  ...