Securing Kubernetes Clusters

Mastering Network Policies: Essential Strategies for Kubernetes Security

Implementing Effective Isolation and Communication Controls within Kubernetes Environments

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Table of Contents

Network Policies
Network Policy Example
Default Policy Example

Network Policies

While setting up network policies is done by cluster administrators, it is important to understand how they work and could prevent our microservices from communicating with each other or outside the cluster.

By default, all pods can reach each other all ingress and egress traffic is allowed. This has been a high-level networking requirement in Kubernetes. However, network isolation can be configured and traffic to pods can be blocked. In newer versions of Kubernetes, egress traffic can also be blocked. This is done by configuring a NetworkPolicy. As all traffic is allowed, we may want to implement a policy that drops all traffic, then, other policies which allow desired ingress and egress traffic.

The spec of the policy can narrow down the effect to a particular namespace, which can be handy. Further settings include a…