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Maintaining the T640 SCGs



For optimum router performance, verify the condition of the SCGs.


On a regular basis:

  • Check the SCG LEDs. During normal operations:

    • The green OK LED on the SCG faceplate is lit.

    • The yellow FAIL LED on the SCG faceplate is not lit.

    • The blue MASTER LED on the SCG faceplate indicates which SCG is the master.

    For more information, see T640 SONET Clock Generators (SCGs) Description.

  • Issue the show chassis environment scg command to display information about the SCGs. The output is similar to the following:

    user@host> show chassis environment scg

    For further description of the output from the commands, see show chassis environment scg.