Kubernetes Network Policy.

Kubernetes Network Policy is namespace scoped. Policies are applied to pods using label selectors. Policy rules can specify the traffic that is allowed to/from pods, namespaces, or CIDRs.

Description.

• This repo contains code which will only allow frontend and backend namespace to communicate. It will also allow communication from the frontend and backend namespace to the kube-dns pod running in the kube-system namespace.
• Pods running in the Kubernetes cluster use the kube-dns service for resolving service names to IPs.
• Network Policy manifest present in this repo can be used in Calico and Cilium CNI as both CNI support Kubernetes Network Policy.

Manifest.

As we know that Kubernetes network policy is namespace scoped, so we have created 2 manifest files, one for the frontend namespace and one for the backend namespace. frontend.yaml file contains network policy for frontend namespace and backend.yaml file contains network policy for backend namespace.

Default deny.

deny.yaml file contains network policy which will block all Ingress and Egress traffic in a namespace.