implementing-kubernetes-network-policy-with-calico

# Implementing Kubernetes Network Policy with Calico ## Overview Calico is an open-source CNI plugin that provides fine-grained network policy enforcement for Kubernetes clusters. It implements the full Kubernetes NetworkPolicy API and extends it with Calico-specific GlobalNetworkPolicy, supporting policy ordering, deny rules, and service-account-based selectors. ## When to Use - When deploying or configuring implementing kubernetes network policy with calico capabilities in your environment - When establishing security controls aligned to compliance requirements - When building or improving security architecture for this domain - When conducting security assessments that require this implementation ## Prerequisites - Kubernetes cluster (v1.24+) - Calico CNI installed (v3.26+) - `kubectl` and `calicoctl` CLI tools - Cluster admin RBAC permissions ## Installing Calico ### Operator-based Installation (Recommended) ```bash # Install the Tigera operator kubectl create -f https://raw.githubusercontent.com/projectcalico/calico/v3.27.0/manifests/tigera-operator.yaml # Install Calico custom resources kubectl create -f https://raw.githubusercontent.com/projectcalico/calico/v3.27.0/manifests/custom-resources.yaml # Verify installation kubectl get pods -n calico-system watch kubectl get pods -n calico-system # Install calicoctl kubectl apply -f https://raw.githubusercontent.com/projectcalico/calico/v3.27.0/manifests/calicoctl.yaml ``` ### Verify Calico is Running ```bash ...