This comprehensive guide explains Kubernetes networking fundamentals, compares major CNI plugins such as Flannel, Calico, and Cilium, and provides detailed troubleshooting steps for pod communication, service routing, DNS issues, and eBPF‑based enhancements, helping operators build reliable, high‑performance clusters.
A late‑night production outage caused by a mis‑configured RBAC role sparked a deep dive into Kubernetes security, covering the principle of least privilege, proper ServiceAccount usage, network policies, audit scripts, and a practical checklist to harden clusters and avoid costly incidents.
This guide explains why Kubernetes security is critical, presents a layered defense architecture, and provides practical steps—including RBAC least‑privilege enforcement, network‑policy zero‑trust design, Pod Security Standards, monitoring rules, and automation scripts—to harden production clusters while avoiding common pitfalls.
This comprehensive guide explains Kubernetes' core networking model, CNI plugins, service networking, ingress, network policies, DNS, service mesh, advanced CNI features, kube‑proxyless alternatives, multi‑cluster setups, security, observability, and troubleshooting techniques for building high‑performance, secure, and observable clusters.
This article explains why Kubernetes namespaces are essential for logical isolation, outlines their core functions such as resource naming separation, RBAC scopes, quota limits and network policies, and provides practical commands, YAML examples, troubleshooting tips, and automation strategies for managing namespaces at scale.
This article shares hard‑earned Kubernetes production lessons, covering RBAC misconfigurations, network‑policy design, real‑world pitfalls, auditing techniques, automation scripts, and recommended security tools to help you prevent costly security incidents.
This article walks you through practical Kubernetes hardening techniques—including fine‑grained RBAC, zero‑trust network policies, Pod Security Standards, real‑time monitoring, and automation—to protect production clusters from privilege abuse and network breaches.
This guide walks you through securing an Ubuntu‑hosted Kubernetes cluster by configuring system settings, firewall rules, TLS encryption, network policies, RBAC permissions, audit logging, and verification steps, providing a layered defense strategy for production environments.
Learn how to correctly install, configure, and activate Calico's API server on a Kubernetes cluster—including prerequisites, downloading manifests, adjusting namespaces, pulling and tagging images, generating certificates, applying resources, and verifying the service—to manage Calico custom resources via kubectl.
This article explains Kubernetes NetworkPolicy concepts, syntax, and practical use cases, providing step‑by‑step YAML examples that show how to deny all traffic, allow intra‑namespace communication, restrict by labels, namespaces, IP ranges, and specific ports, plus key considerations for deployment.
This comprehensive guide explains the fundamentals of CNI plugins, details Calico's architecture and network modes, walks through installation via manifest or Tigera Operator, covers configuration of CIDR blocks, IPIP/VXLAN encapsulation, network policies, and provides step‑by‑step instructions for full deployment and clean uninstallation in Kubernetes clusters.
Learn the critical Kubernetes security measures for production environments, including RBAC access control, network policies, secret management, continuous monitoring, patch updates, API server hardening, Kubelet protection, pod security policies, and container hardening techniques, each illustrated with practical YAML examples and command snippets.
This article explains how to integrate security into the DevOps pipeline for Kubernetes, covering DevSecOps concepts, image protection, role‑based access control, network policies, encryption, etcd safeguarding, and disaster‑recovery strategies to keep clusters safe and releases fast.
This article explains the concept of multi‑tenant Kubernetes clusters, outlines common enterprise scenarios, and details native security mechanisms such as RBAC, NetworkPolicy, PodSecurityPolicy, OPA, resource quotas, and dedicated nodes to achieve effective isolation and protect sensitive data.
The article analyzes how Cilium’s eBPF‑based architecture, advanced network policies, cluster‑wide traffic control, and observability tools like Hubble solved performance, security, and scalability challenges that Flannel and kube‑proxy could not meet in production Kubernetes environments.
This article introduces common container network scenarios and explains how various Kubernetes CNI plugins—Kube‑OVN, Antrea, Cilium, Calico, Flannel, Submariner, and others—implement these functions, guiding users on selecting and deploying the appropriate plugin with tools like Kubekey for multi‑cluster and policy needs.
This article explains Kubernetes NetworkPolicy, covering its purpose, how pod and namespace selectors work, required fields, policy types, and detailed YAML examples, followed by practical scenarios and step‑by‑step commands for deploying and testing network policies in a cluster.
The article provides a comprehensive overview of Kube-OVN, a powerful Kubernetes CNI plugin that leverages OVS to deliver enterprise‑grade overlay and underlay networking, multi‑NIC management, security policies, performance tuning, and monitoring, while also outlining its architecture, usage steps, and community resources.
This article uses a fish‑and‑aquarium analogy to demystify core Kubernetes concepts such as Pods, Services, ReplicaSets, ConfigMaps, and Network Policies, illustrating how applications run, scale, and communicate within a cluster.
This article explains how Kubernetes hierarchical namespaces (HNC) enable secure multi‑tenant clusters by extending basic namespace capabilities with ownership, policy inheritance, and delegated creation rights, and demonstrates usage through kubectl commands and NetworkPolicy examples.
This article provides a comprehensive guide to Calico as a Kubernetes CNI, covering its BGP‑based three‑layer architecture, deployment steps, configuration of etcd certificates, management tools, BGP route‑reflector mode, IPIP tunneling, and network policy implementation for cloud‑native clusters.
This article explains the concept of multi‑tenant Kubernetes clusters, distinguishes soft and hard isolation, describes common enterprise and SaaS/KaaS scenarios, and provides step‑by‑step guidance on using native Kubernetes features such as RBAC, NetworkPolicy, PSP, OPA, resource quotas, pod priority, node taints, and secret encryption to achieve robust security isolation.
This article explains Kubernetes’ fundamental network model, detailing the three core constraints and four design goals, exploring network namespaces, comparing Underlay and Overlay approaches, reviewing popular CNI solutions such as Flannel, Calico, Cilium and WeaveNet, and outlining practical NetworkPolicy configuration steps.
Kube-OVN 0.5 introduces full Kubernetes NetworkPolicy support via Openflow, customizable container interfaces and MTU, automatic system parameter tuning, auto‑computed default gateways, and additional CLI options, while its open‑source design brings comprehensive OVN‑based networking features to Kubernetes across diverse platforms.
This article explains Kubernetes native NetworkPolicy, covering its purpose, supported CNI plugins, detailed field definitions, default behaviors, example policies, and historical changes, providing a comprehensive guide for configuring pod communication rules in a cloud‑native environment.
This article explains how Kubernetes NetworkPolicy works with Calico, detailing the policy creation process, configuration templates, component versions, deployment steps, Calico‑felix packet handling, and a practical “deny all traffic” test case, concluding with operational considerations and reference links.
This article explains how Kubernetes NetworkPolicy provides namespace‑ and pod‑level network isolation, how Calico translates policies into iptables rules, and walks through configuration templates, test setups, runtime details, packet‑flow analysis, and practical considerations for production use.
