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The supervisor engine faces issues due to an NVRAM checksum error on a Cisco Catalyst 6000 Series switch that runs Catalyst OS system software

Core issue

In rare circumstances, Cisco Catalyst 6000 Series switches can experience a red status light on the supervisor module due to an NVRAM checksum error.

These are the results of this condition:

  • The output of the show version command shows a checksum failure of some type.
  • The output of the show test 1 command displays NVRAM:F.

This problem does not impact an operational switch unless configuration changes are made while the switch is in this condition. Refer to Cisco bug ID CSCdx87646.


As a workaround, reset the supervisor module.

Note: Some configuration data can be lost when the switch is reset. Before the switch is reset, be sure to make a copy of the current configuration, and store the copy on another device. In order to accomplish this, issue the show configuration command. Then copy and paste the configuration to a text file.

Catalyst Operating System (CatOS) version 6.4(1) contains a fix for this bug. Refer to Cisco bug ID CSCdz32620.

The fix is also integrated in versions 8.1(1), 7.5(0.19), 7.5(0.28), 8.1(0.10)KIS, and 7.7(0.10)KIS.

Refer to Cisco Catalyst 6000 Series Switches Troubleshoot and Alerts for software downloads and more information.

Module LED status


System LED status