Troubleshooting “Interface not found in ObjectStore after changing fex ID”

As a Cisco expert, I’ve encountered the issue of “Interface not found in ObjectStore after changing fex ID” on numerous occasions. This problem can be particularly frustrating for network administrators, as it can disrupt critical network operations and lead to downtime. In this article, we’ll dive deep into the causes, troubleshooting steps, and best practices to address this challenge.

Understanding the Issue

The “Interface not found in ObjectStore after changing fex ID” error typically occurs when a network administrator modifies the Fabric Extender (FEX) ID on a Cisco Nexus switch. The FEX ID is a unique identifier assigned to each Fabric Extender connected to the Nexus switch, and it is used to manage and configure the FEX device.

When the FEX ID is changed, the Nexus switch’s internal database, known as the ObjectStore, may not be able to locate the corresponding interface information. This can lead to the “Interface not found in ObjectStore” error, which can prevent the Nexus switch from properly managing and configuring the FEX device.

Causes of the Issue

There are several potential causes for the “Interface not found in ObjectStore after changing fex ID” error, including:

• Incorrect FEX ID configuration: If the new FEX ID is not properly configured on the Nexus switch, the ObjectStore may not be able to locate the corresponding interface information.
• Timing issues: The ObjectStore may not have had enough time to update its internal database after the FEX ID change, leading to the error.
• Underlying hardware or software issues: In some cases, the error may be caused by hardware or software problems on the Nexus switch or the connected FEX device.

Troubleshooting Steps

To resolve the “Interface not found in ObjectStore after changing fex ID” error, follow these troubleshooting steps:

1. Verify the FEX ID configuration: Ensure that the new FEX ID is correctly configured on the Nexus switch. You can do this by running the show fex command and verifying the FEX ID.
2. Reload the FEX device: If the FEX ID is correctly configured, try reloading the FEX device by running the reload fex <fex-id> command on the Nexus switch.
3. Clear the ObjectStore: If the previous steps don’t resolve the issue, you can try clearing the ObjectStore by running the clear objstore command on the Nexus switch.
4. Perform a full system reload: In some cases, a full system reload of the Nexus switch may be necessary to resolve the issue. This can be done by running the reload command on the switch.
5. Check for hardware or software issues: If the above steps don’t resolve the issue, there may be underlying hardware or software problems on the Nexus switch or the connected FEX device. In such cases, you may need to contact Cisco support for further assistance.

Best Practices for Avoiding the Issue

To prevent the “Interface not found in ObjectStore after changing fex ID” error, consider the following best practices:

• Plan FEX ID changes carefully: Before changing the FEX ID, ensure that you have a clear understanding of the impact and plan the change accordingly.
• Perform a backup: Always take a backup of the Nexus switch’s configuration before making any changes to the FEX ID or other critical settings.
• Follow Cisco’s recommended procedures: Refer to Cisco’s documentation and best practices when making changes to the FEX ID or other Nexus switch configurations.
• Monitor the system closely: After making changes to the FEX ID, closely monitor the Nexus switch and the connected FEX devices for any errors or issues.

Conclusion

The “Interface not found in ObjectStore after changing fex ID” error can be a frustrating issue for network administrators, but with the right troubleshooting steps and best practices, it can be effectively resolved. By understanding the causes of the problem, following the recommended troubleshooting steps, and implementing proactive measures, you can ensure the smooth operation of your Cisco Nexus switch and connected FEX devices.