This folder contains information and tools for debugging Kubernetes networking issues.

1. Check Pod Networking:

   • Use kubectl get pods -o wide to view pod IPs.
   • Use ping or curl to test connectivity between pods.

2. Inspect Network Policies:

   • Use kubectl get networkpolicy to list network policies.
   • Verify that policies are not blocking traffic.

3. Verify CNI Plugin:

   • Check logs of the CNI plugin pods (e.g., kubectl logs -n kube-system <cni-pod-name>).

4. Inspect Node Networking:

   • Use ifconfig or ip a on nodes to check network interfaces.
   • Use iptables to inspect firewall rules.

5. Inspect Configuration:

   • Review the CNI plugin configuration file (e.g., /etc/cni/net.d/).

• kubectl
• Network tools like ping, curl, traceroute.
• Node tools like ifconfig, ip a, iptables.

Problem: Pods cannot communicate with each other.

Solution:

1. Check pod IPs: kubectl get pods -o wide.
2. Test connectivity: ping <pod-ip> or curl http://<pod-ip>:<port>.
3. Inspect network policies: kubectl get networkpolicy.
4. Verify CNI plugin logs: kubectl logs -n kube-system <cni-pod-name>.