Kubernetes networking is a complex topic, but it is essential for understanding how pods communicate with each other and with the outside world. In this blog post, we will provide a high-level overview of Kubernetes networking.
The Kubernetes networking model is based on the concept of pods. Each pod has its own IP address and can communicate directly with other pods in the same namespace. Services are used to group pods together and provide an entry point for external traffic. Network policies can be used to restrict traffic between pods. Kubernetes also supports incoming traffic from outside the cluster through Ingress resources.
Kubernetes does not have its own built-in networking implementation. Instead, it relies on network plugins to provide the specific networking functionality. There are many different network plugins available, each with its own strengths and weaknesses. Some popular network plugins include Calico, Flannel, and Weave Net.
Overlay networks
Many Kubernetes network implementations use overlay networks. In an overlay network, pod IP addresses are not routable outside the cluster. This means that pods can only communicate with each other and with external services that are also part of the overlay network.
Challenges of Kubernetes networking
One of the biggest challenges of Kubernetes networking is managing east-west traffic (traffic between pods) and north-south traffic (traffic between pods and the outside world). East-west traffic can be complex to manage because pods can be created and destroyed dynamically. North-south traffic can also be complex to manage because you need to configure firewalls and other security controls to allow only authorized traffic into the cluster.
Kubernetes networking is a complex topic, but it is essential for understanding how pods communicate with each other and with the outside world. In this blog post, we have provided a high-level overview of Kubernetes networking. We hope this information has been helpful.