Need Help with CoreDNS Error on Kafka Setup

This type of error usually means the pod network isn't configured correctly, which leads to DNS lookup failures because the pods can't communicate with the DNS server. Since you're using kubeadm, examine your CNI plugin to ensure it's healthy. Run `kubectl get pods -n kube-system` to check for pods in CrashLoopBackOff or any other states that indicate issues. Also, try an nslookup inside your Kafka pod to see if it can resolve service names—this can help pinpoint where the breakdown is happening.

It sounds like you might be dealing with a network issue between your Kafka pod and ZooKeeper. CoreDNS is throwing errors because your pods can't access the DNS server at 172.19.0.126, which likely points to a CNI (Container Network Interface) problem. Check if your CNI plugin is properly installed and functioning. Restarting the pods or even the node might help, but you should dig deeper into the network setup of your Kubernetes cluster if that doesn’t work.

There may be a routing issue causing the connectivity problems to 172.19.0.126. You could try attaching a debug container to the Kafka bootstrap and see if you can reach the host from there. If something in your setup got misconfigured, a simple restart of your CoreDNS deployment might fix it. Also, make sure to check your Kubelet’s clusterDomain settings.