Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?

 

Troubleshooting the T640 SONET Clock Generators

 

Problem:

Description:

The following alarms and LEDs indicate a problem with an SCG:

  • The yellow FAIL LED on the SCG faceplate is lit.

  • The green OK LED on the SCG faceplate is not lit.

  • A red alarm indicates that an SCG, SCG voltage sensor, or the internal clock has failed.

  • A red alarm indicates that there are no SCGs online.

  • A red alarm indicates that loss of signal has occurred from an external clocking device connected to the RJ-48 Aor B port.

  • A yellow alarm indicates that an SCG is not online in a router with redundant SCGs or that an SCG has been removed..

  • A yellow alarm indicates that a temperature sensor has failed.

In Table 1, the text in the column labeled ”LCD Message” appears in the display of the craft interface. The text in the column labeled “CLI Message” appears in the output from the show chassis alarms command.

Table 1: SCG Alarm Messages

Alarm Type

LCD Message

CLI Message

Red

RED ALARMSCG SCG-number Failure

RED ALARMSCG SCG-number Failure

RED ALARMNo SCG Online

RED ALARMNo SCG Online

RED ALARMSCG SCG-numberVolt Snsr Fail

RED ALARMSCG SCG-numberVolt Sensor Fail

RED ALARMSCG SCG-numberExt-A LOS

RED ALARMSCG SCG-numberExternal-A LOS

RED ALARMSCG SCG-numberExt-B LOS

RED ALARMSCG SCG-numberExternal-B LOS

RED ALARMSCG SCG-numberINT CLK Fail

RED ALARMSCG SCG-numberInternal Clock Failure

Yellow

YELLOW ALARMSCG SCG-number Not Online

YELLOW ALARMSCG SCG-number Not Online

YELLOW ALARMSCG SCG-number Removed

YELLOW ALARMSCG SCG-number Removed

YELLOW ALARMSCG SCG-numberTmpSnsr Fail

YELLOW ALARMSCG SCG-numberTemp Sensor Fail

Solution

To troubleshoot the SCGs:

  1. Check the LEDs on the faceplate of each SCG and on the craft interface.
  2. Use the CLI to check for alarms.
    • Standalone router—Issue the show chassis alarms command to view the alarms.

    • Router in a routing matrix—Issue the show chassis alarms lcc lcc-number command to view the alarms.