implementing-container-network-policies-with-calico

# Implementing Container Network Policies with Calico ## Overview Calico provides Kubernetes-native and extended network policy enforcement through its CNI plugin. This skill covers creating and auditing Calico NetworkPolicy and GlobalNetworkPolicy resources to implement pod-to-pod traffic control, namespace isolation, egress restrictions, and DNS-based policy rules using calicoctl and the Kubernetes API. ## When to Use - When deploying or configuring implementing container network policies 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 with Calico CNI installed - Python 3.9+ with `kubernetes` client library - calicoctl CLI tool installed and configured - kubectl access with RBAC permissions for network policy management ## Steps ### Step 1: Audit Existing Network Policies Use calicoctl and kubectl to inventory current network policies and identify unprotected namespaces. ### Step 2: Implement Default-Deny Policies Create default-deny ingress and egress policies per namespace as a zero-trust baseline. ### Step 3: Create Workload-Specific Allow Rules Define granular allow rules for legitimate pod-to-pod and pod-to-service communication. ### Step 4: Validate Policy Enforcement Test connectivity between pods to verify policies are correctly enforced. ## Expected Output JSON audit report listing all network policies, unprotected namespaces, policy rule counts, and connectivity test results.