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.
This guide explains Kubernetes Service concepts, the different Service types and ports, introduces MetalLB as a LoadBalancer solution for bare‑metal clusters, walks through its installation, configuration, testing, integration with Ingress, and also covers Calico networking fundamentals and architecture.
This article explains the Kubernetes network model, introduces the CNI standard, and compares four popular network plugins—Flannel, Calico, Weave Net, and Cilium—highlighting their features, advantages, and suitable use cases for different cluster sizes and requirements.
This comprehensive guide walks you through Kubernetes' network model, explains why networking is its biggest pain point, compares major CNI plugins with real‑world performance data, and provides a step‑by‑step decision framework, tuning tips, troubleshooting methods, and monitoring best practices for production environments.
This guide walks through a real‑world Kubernetes incident where a pod experienced packet loss, detailing how to identify the impact scope, observe drop patterns, trace the veth pair, capture traffic with tcpdump, and resolve the issue by disabling the unnecessary lldpd service.
This comprehensive guide explains Kubernetes' layered architecture, core components, and container networking fundamentals, covering IP‑per‑Pod, CNI plugins, Flannel and Calico implementations, DNS, Service types, Ingress, and public‑cloud networking strategies for multi‑cluster deployments.
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.
Learn step‑by‑step how to transition Calico’s data store from etcd to Kubernetes, covering prerequisite checks, locking the datastore, exporting and importing data, reconfiguring calicoctl, applying the new manifests, and unlocking the store, while highlighting benefits and tips for a smooth migration.
This guide walks through installing calicoctl, a Calico command‑line tool for managing Kubernetes network policies, covering prerequisites, manifest deployment for both Kubernetes‑ and etcd‑backed data stores, verification commands, and practical tips for a smooth setup.
This guide walks through preparing two CentOS 7.9 servers, installing Docker and Kubernetes 1.19 components, initializing a master node, joining a worker node, and validating the cluster with a sample Nginx deployment, including common troubleshooting tips.
This guide explains how to upgrade a Kubernetes cluster from v1.30.0 to v1.30.1 without service interruption by backing up etcd, checking health, planning the rollout, upgrading master nodes and Calico, and using rolling updates and Istio canary releases for seamless application migration.
This guide walks you through setting the download region, installing KubeKey and required dependencies, generating a configuration file, creating a single‑node or multi‑node Kubernetes cluster with containerd, and verifying the deployment using kubectl, all with clear command examples and screenshots.
This guide explains Kubernetes Service types, the role of MetalLB in providing LoadBalancer functionality for bare‑metal clusters, step‑by‑step installation, configuration of address pools, testing with a sample service, integration with Ingress, and an overview of the Calico network plugin for pod isolation.
This article explains the core principles, advantages, suitable scenarios, and step‑by‑step configuration of Calico's BGP mode, showing how it delivers high‑performance, scalable, and secure networking for large Kubernetes deployments.
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.
This article compares Flannel and Calico, two Kubernetes CNI plugins, detailing their architectures, backend mechanisms, routing models, overlay and non‑overlay options, and highlighting Flannel's simplicity for small clusters versus Calico's richer feature set for larger, production‑grade environments.
This guide walks you through setting up a comprehensive Kubernetes monitoring solution—covering component metrics collection, configuring HAProxy for network access, exposing metrics from kube-proxy, Calico, and kube-state-metrics, and integrating everything into Prometheus for reliable cluster health visibility.
This comprehensive course provides a deep dive into Kubernetes networking, covering core concepts, network models, policies, plugins, traffic management, security, multi‑tenant, cross‑cloud, and hybrid‑cloud designs, and offers hands‑on performance optimization techniques across more than 60 video modules.
This article introduces the five most popular Kubernetes CNI network plugins—Flannel, Calico, Weave Net, Cilium, and Canal—detailing their features, typical use‑cases, and installation commands to help you choose the right solution for your cluster.
This guide explains the background of Multus CNI, details its architecture and CNI type classification, and provides step‑by‑step commands to deploy Multus alongside Calico and Flannel, configure network interfaces, modify Calico IP detection, and verify multi‑network pod connectivity in a Kubernetes cluster.
This guide explains the background, architecture, and step‑by‑step deployment of Multus CNI in a Kubernetes cluster, including configuring Calico and Flannel as primary and secondary networks, creating network attachment definitions, and testing pod connectivity across multiple interfaces.
This guide explains why Multus CNI is needed for multi‑network pods in Kubernetes, describes its architecture, walks through installing Multus alongside Calico and Flannel, shows how to configure NetworkAttachmentDefinitions, adjust Calico’s NIC selection, and demonstrates testing pod connectivity and routing limitations.
This article provides a comprehensive overview of Kubernetes network architecture, including CNI plugins, network policies, service discovery, and ingress controllers, with practical configuration examples.
This article examines Kubernetes networking models, detailing underlay and overlay concepts, the role of layer‑2/3 infrastructures, and how CNI plugins like Flannel, Calico, IPVLAN, Multus, and DANM implement these models for efficient pod communication.
This article provides a detailed overview of Calico's essential and optional components, explaining how each part—such as the API server, Felix, BIRD, confd, Dikastes, CNI plugin, datastore plugin, IPAM plugin, kube‑controllers, Typha, and calicoctl—contributes to networking and network policy enforcement in Kubernetes clusters.
This article explains the fundamentals of Kubernetes networking, describes its flat network architecture, reviews common CNI implementations such as Flannel, Project Calico, and Weave Net, and details the various communication pathways including container‑to‑container, pod‑to‑pod, pod‑to‑service, and internet‑to‑service.
This article explains Kubernetes' networking architecture by detailing the underlay and overlay models, comparing layer‑2 and layer‑3 designs, and reviewing common CNI implementations such as Flannel, Calico, Multus, and DANM, along with their underlying technologies.
This guide explains why a Calico pod shows "BIRD is not ready: BGP not established" in a Kubernetes cluster, identifies the missing node interface detection as the root cause, and provides step‑by‑step instructions to adjust the IP autodetection method and restore pod health.
This article explains Kubernetes networking models, detailing the underlay network infrastructure, overlay techniques, and common CNI implementations such as Flannel, Calico, IPVLAN, and VxLAN, while comparing their architectures, protocols, and configuration considerations.
This article explains Calico's IPIP networking mode in Kubernetes, covering its architecture, core components, routing behavior, command‑line examples, and packet‑capture analysis to illustrate how pods communicate across nodes.
This article provides a comprehensive overview of Kubernetes networking by explaining the concepts of underlay and overlay network models, describing their implementations such as flannel host‑gw, Calico BGP, IPVLAN/MACVLAN, and tunneling technologies like VxLAN and IPIP, and offering practical references for each approach.
This article provides a comprehensive overview of Kubernetes networking, explaining the concepts of underlay and overlay network models, their implementations with Flannel, Calico, IPVLAN, MACVLAN, Multus, DANM, and common tunneling protocols such as VxLAN, IPIP, and GRE, while highlighting practical configuration notes and architectural differences.
This tutorial walks through using QingCloud Load Balancer to create a fault‑tolerant Kubernetes cluster, covering host inventory, OS preparation, kernel upgrades, Docker and kubeadm installation, master initialization, node expansion, Calico networking, and metrics‑server setup.
This comprehensive guide walks you through installing a Kubernetes cluster with kubeadm, configuring containerd, initializing master and worker nodes, deploying Calico networking and the Dashboard, performing upgrades, renewing certificates, adding or removing nodes, and backing up both etcd data and cluster manifests using scripts and Velero.
This article systematically explains container cloud network architecture, covering fundamental concepts, protocol stacks, traversal and isolation methods, Docker and Kubernetes networking models, and a detailed comparison of CNI solutions such as Flannel, OVS, and Calico.
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.
This guide explains how to configure Calico networking in Kubernetes clusters, covering the supported modes (IPIP, BGP, cross‑subnet), route reflector setup, MTU tuning, AS number configuration, IP pool management, SNAT disabling, and assigning fixed pod IPs.
This article explains how Kubernetes ensures container-to-container communication using network namespaces, veth pairs, bridges like docker0, and advanced CNI plugins such as Flannel and Calico, detailing their underlying Linux networking components, routing mechanisms, and deployment considerations for both intra‑host and inter‑host scenarios.
This article explains the fundamentals of Kubernetes networking, compares popular CNI implementations such as Flannel, Calico, and Weave Net, and details the key networking scenarios—including container‑to‑container, pod‑to‑pod, pod‑to‑service, and Internet‑to‑service—required for reliable and secure cluster operation.
This article explains the fundamentals of container networking in Kubernetes, covering network namespaces, veth pairs, bridges, CNI plugins such as Flannel and Calico, their routing modes, and practical command‑line examples that illustrate intra‑host and cross‑host communication.
This guide walks through setting up a cross‑subnet Kubernetes cluster with Calico in pure BGP mode by simulating routers and networks using ENSP and a workstation, covering architecture design, ENSP routing configuration, node integration, Calico BGP settings, and verification of pod communication.
This article explains Kubernetes container networking fundamentals, covering pod-to-pod communication, Linux network namespaces, veth pairs, bridges, and the various CNI plugins such as Flannel and Calico that enable cross‑host networking with overlay, routing, and underlay modes.
This article explains how Tigera’s Calico integrates the open‑source WireGuard VPN with Azure Kubernetes Service using Azure CNI, detailing packet flow, encryption benefits, configuration steps, MTU handling, and RPF considerations to achieve secure, high‑performance intra‑cluster communication.
This article explains Kubernetes container networking fundamentals, the role of Linux network namespaces, veth pairs, bridges, and iptables, and compares same‑host communication via docker0 with cross‑host solutions like CNI plugins (flannel, Calico) and their routing modes.
This article explains how Kubernetes enables container-to-container communication using network namespaces, veth pairs, bridges, and CNI plugins such as Flannel and Calico, covering both intra‑host networking with docker0 and cross‑host networking models, routing rules, and BGP‑based solutions.
This article explains the fundamentals of container networking in Kubernetes, covering Linux network namespaces, veth pairs, Docker's default bridge, CNI plugins such as Flannel and Calico, their routing modes, and practical command‑line examples for cross‑host communication.
This article details Qunar's adoption of Calico as a CNI solution, covering its three‑layer architecture, core components, large‑scale deployment practices, IPAM behavior, pod‑to‑pod and pod‑to‑external traffic flows, encountered issues, and the overall benefits for a production Kubernetes environment.
This article provides a detailed walkthrough of the Calico CNI plugin source code, explaining how the calico and calico‑ipam binaries are built, how the ADD command creates WorkloadEndpoint objects, veth pairs, routes, and sysctl settings, and how these components integrate with the Calico datastore in a Kubernetes environment.
This article explains how traffic packets travel from external IPs or node ports to Kubernetes pods using ExternalIP ClusterIP services, NodePort services, iptables DNAT/SNAT rules, and Calico BGP routing, with step‑by‑step analysis, configuration examples, and command‑line inspections.
This article explains the fundamentals of Kubernetes container networking, covering the network stack, bridge, veth pairs, host networking, ARP resolution, and then dives into cross‑host communication methods, comparing Overlay solutions such as Flannel and Calico with Underlay approaches like BGP, illustrated with concrete commands and diagrams.
This article explains Calico’s IPIP networking mode in Kubernetes, detailing its architecture, core components, routing behavior, packet encapsulation, and practical verification through ping tests, route inspection, and packet captures, helping readers understand cross‑node pod communication.
This article examines Calico’s IPIP networking mode in Kubernetes, detailing its architecture, core components, IPIP vs BGP operation, route analysis, packet‑capture findings, and pod‑to‑service communication to illustrate how IP encapsulation facilitates cross‑node traffic.
This article explains the step‑by‑step process by which kubelet creates a sandbox container, invokes the CNI interface, runs Calico’s ADD command, and sets up routes, virtual interfaces, and IP allocation for pods in a Kubernetes cluster, including relevant Go code excerpts.
This article explains Docker's container networking fundamentals, covering single‑host communication modes (host, bridge, none, container‑shared, custom), their advantages and drawbacks, and then delves into cross‑host solutions such as overlay, Weave, and Calico, comparing their architectures and performance implications.
This article explains the fundamental principles of Kubernetes container networking, covering network namespaces, veth pairs, bridges, iptables, and routing, and compares intra‑host communication with cross‑host solutions such as CNI plugins, overlay, host‑gw, and Calico’s BGP‑based approaches.
This article explains the fundamental principles of Kubernetes container networking, how Docker’s default bridge and veth pairs connect pods on the same host, and compares various CNI plugins and routing models for cross‑host communication, including Flannel and Calico.
This article explains the fundamental principles of container networking in Kubernetes, covering pod-to-pod communication, Linux network namespaces, veth pairs, Docker bridge, and advanced CNI plugins such as Flannel and Calico, including their overlay, routing, and underlay modes with practical command 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.
The article answers a technical question about using Calico as the network mode in container cloud networks, explaining that Calico relies on three‑layer routing with BGP, requiring hardware BGP support and sufficient processing capacity to host the full‑mesh routing for all nodes.
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 walks you through deploying Flannel (host‑gw and VXLAN modes) and Calico (IP‑IP mode, RR deployment, and BGP configuration) on a Kubernetes cluster using systemd units, etcd backend settings, and detailed CNI configuration files, complete with troubleshooting tips and code snippets.
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.
This article details the evolution of Tongcheng Travel’s PaaS platform, describing its shift from Docker Swarm host networking to a custom container network using Calico and Contiv, the implementation of public‑IP allocation, and the monitoring solution built with OVS sFlow, Redis and ELK.
