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May 12, 2024
2 min read

Navigating CoreDNS Errors in Kubernetes

Learn how to troubleshoot CoreDNS errors in Kubernetes and keep your cluster running smoothly.
  • ChatGPT

Introduction

Are you encountering errors with CoreDNS in your Kubernetes cluster? Don’t fret! In this guide, I’ll walk you through troubleshooting steps to resolve CoreDNS issues and ensure your cluster operates seamlessly.

Understanding CoreDNS Errors

If you’re facing errors related to CoreDNS, it’s likely due to it being stuck in a crash loop back state. This can occur when DNS is invoked from /etc/resolv.conf. To tackle this issue, we need to modify the forwarding path to the DNS address.

Troubleshooting Steps

To resolve CoreDNS errors, follow these steps:

  1. Edit CoreDNS ConfigMap: Use the following command to edit the CoreDNS ConfigMap:

    kubectl edit configmap coredns -n kube-system
    
  2. Update Forwarding Path: Within the ConfigMap, locate the forward configuration and modify the DNS address accordingly.

  3. Save Changes: Once you’ve made the necessary modifications, save the changes to the ConfigMap.

  4. Restart CoreDNS: Restart the CoreDNS deployment to apply the changes:

    kubectl rollout restart deployment coredns -n kube-system
    
  5. Monitor CoreDNS Logs: Keep an eye on CoreDNS logs to ensure that the changes have been applied successfully.

Conclusion

By following these troubleshooting steps, you can effectively address CoreDNS errors and maintain the stability of your Kubernetes cluster. Remember to stay vigilant and monitor your cluster for any further issues. Happy troubleshooting!

Best regards,
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