Runbook

CoreDNS Query Failures

Overview

CoreDNS Query Failures is an incident type that indicates that there is an issue with the CoreDNS service which is responsible for resolving DNS queries in a system. This incident can occur due to various reasons such as network connectivity issues, DNS misconfiguration, or a bug in the CoreDNS software itself. When this incident happens, users may experience difficulties accessing services or websites that rely on DNS resolution. Troubleshooting this incident requires identifying the root cause and implementing a solution to resolve the issue and restore normal functionality.

Parameters

Debug

Next Step

Check logs of CoreDNS pods for errors or failures

Get detailed information about the CoreDNS Deployment

Check the status of the CoreDNS Service

Check if the CoreDNS ConfigMap is correct

Check if the Kubernetes DNS service is running

Check if the Kubernetes DNS ConfigMap is correct

Check if the pod's DNS settings are correct

Check if the DNS policy for the pod is set to the correct value

Check if there are any network connectivity issues

Repair

Restart the CoreDNS service: If the issue is isolated to the CoreDNS service, restarting the service may be enough to resolve the issue.

Verify DNS configuration: Ensure that the DNS configuration is correct and that the CoreDNS service is configured to use the correct DNS servers. Misconfiguration of DNS can cause query failures and lead to this incident type.

Learn more

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