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Core issue

The Catalyst fixed configuration switch will not power on.


To resolve this issue, perform these steps:

  1. If all LEDs (including the system LED) are off, make sure the power switch is on and that all the connections to and from the power supply are securely connected. Make sure the power outlet has power and that it is the right type of power. If the switch is connected to an Uninterrupted Power Supply (UPS) backup power source, plug the switch directly into the wall to eliminate the UPS as the source of the problem.
  2. When the Power-On Self Test (POST) completes successfully, the port status LEDs go out. This indicates that the switch is operational. If a test fails, the port status LED associated with the test displays amber. The system LED also displays amber.
  3. To see if any port failed a POST, issue the show post command on the Catalyst switch when the system is running. The show post command is available with Cisco IOS  Software release 11.2(8.5) SA6 and later. This command checks to see if the POSTs passed. If there is a failure, it determines which POST failed. This command is useful when you are able to get a link on a particular port or the port LED is amber. For example, this output is from a Catalyst 2900XL, which failed a POST on FastEthernet interface 0/19:    
    2900XL# show post
    POST FAILED: FastEthernet 0/19 failed front-end loopback test
  4. Failure of any of these diagnostic tests is normally non-recoverable and usually requires a Return Materials Authorization (RMA) to resolve the problem.    

    For more information on post failures for Catalyst 2900XL and 3500XL switches, refer to the Troubleshooting and Understanding POST Failure Messages section of Troubleshooting Common Issues on the Catalyst 2900XL and 3500XL Series Switches.


    For additional information, refer to Troubleshooting Switch Port and Interface Problems.

  5. If the issue is not resolved, please contact Cisco Technical Support online using the TAC Service Request Tool.
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