Catalyst 2900XL, 3500XL, 2950, 2940, 2955, 2970, 3550 or 3750 switch interface status shows down/down or administratively down

[TCC_2]

Resolution

If the interface has a status of down/down, perform these steps:

1. Verify a connection to the interface.     
2. Check or swap cables and verify the operation of the end device.        
3. Verify that the port LED status is green. If the link LED is amber, the port may have failed the Power-On Self Test (POST). To check, issue the show post command.

   If the interface has failed POST, refer to the Troubleshooting and Understanding POST Failure Messages section of Troubleshooting Common Issues on the Catalyst 2900XL and 3500XL Series Switches.

          
4. If there is no link LED, make sure the interface is not administratively shutdown by issuing the show interface command.        
5. If the interface status is down/down, swap cables. Verify the operation status of the end device and Network Interface Card (NIC).For more information on NIC related issues, refer to Troubleshooting Cisco Catalyst Switches to NIC Compatibility Issues.

   The cause for the interface status of administratively down/down is that the port is manually shutdown. To enable the interface, issue the no shutdown interface-level command.

          
6. If the interface is in up/up status and you are experiencing errors on the 2900XL or 3500XL, refer to these documents:
   • Article Certain counters rapidly increase in the show controllers ethernet controller command output on the Catalyst fixed configuration switches, including alignment, Undersized frames, FCS, transmit and receive errors or various collisions counters
   • The Troubleshooting Interface Errors section of Troubleshooting Common Issues on the Catalyst 2900XL and 3500XL Series Switches

Port LED status

Amber

Not lit