Today, we faced a hiccup with our Kubernetes cluster's internal DNS server. The root cause of this issue was an outdated and unmanaged DNS plugin incompatible with the latest cluster version. Although it went unnoticed during the cluster update, it eventually impacted our services after the local DNS cache expired. Thankfully, we promptly resolved the issue by updating our DNS plugin to a managed version and configuring it to meet the requirements of the current Kubernetes release version. We are confident that this solution will effectively prevent any similar glitches from occurring in the future.