Troubleshooting Kubernetes Network Problems
In Kubernetes networking plays a huge role. It’s ok if you haven’t mastered it yet.
But when you are managing Kubernetes clusters, make sure to nail down these 3 important concepts. Check the video format here.
1. The Private and Public IP addresses.
- Kubernetes uses private IP addresses for Pods.
- They allow Pods to communicate with each other internally.
- Public IPs are used to expose services to outside world gracefully.
2. Linux network routing.
- Knowing routing helps you troubleshoot pod connection failures.
- It helps you understand how packets flow between Pods & Services.
3. Using tcpdump.
- tcpdump is a cool network packet capture tool.
- It simplifies capturing and analyzing network traffic.
- It’s very useful to identify issues like dropped packets and incorrect routing.
Here are 2 more (important) items that will help you in your Kubernetes troubleshooting journey. Following are very useful to fix pod to pod networking.
1. Understanding the CNI (Container Network Interface)
- It assigns IP addresses to pods.
- It also creates virtual networks for pods & does more.
- Some of the popular CNI plugins include Flannel, Cilium and Calico.
In short, CNI can help you understand how network configurations can be done in a Kubernetes cluster.
2. IPTables/IPVS
- Iptables is default kube-proxy mode.
- It configures packet forwarding rules.
- IPVS is an alternate kube-proxy mode to handle traffic distribution.
- This mode is quite handy to handle larger deployments with high traffic.
Each day offers a new chapter. Take every opportunity to learn. Hope it’s useful. I totally appreciate a REPOST ♻
