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Kubernetes - Components

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Kubernetes is built from several core components that work together to run and manage containerized applications. These components are usually grouped into: Control Plane Components (manage the cluster) Node Components (run workloads) 1️ .  Control Plane Components The control plane is responsible for managing the Kubernetes cluster. 1. kube-apiserver The API server is the entry point to the cluster . Everything in Kubernetes goes through it. Responsibilities Exposes the Kubernetes REST API Validates requests Processes CRUD operations for resources Communicates with the cluster datastore Example operations: Creating a Pod Scaling deployments Updating configurations Flow example:   User → kubectl → API Server → etcd   Key points: Stateless Can be horizontally scaled All components talk to it   2. etcd   etcd is the key-value database of Kubernetes.   It stores all cluster state.   Stores ...
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Kubenetes Networking Syllabus

 COMPREHENSIVE KUBERNETES NETWORKING SYLLABUS MODULE 1: Kubernetes Networking Fundamentals 1.1 Container Networking Basics Linux network namespaces veth pairs Linux bridges iptables fundamentals IP routing basics Overlay vs Underlay networking 1.2 Kubernetes Networking Design Principles Every Pod gets an IP Pod-to-Pod communication without NAT Node-to-Pod communication Container-to-Container within Pod Cluster networking architecture 1.3 Kubernetes Networking Architecture Components kube-apiserver kube-controller-manager kube-scheduler kubelet kube-proxy CNI plugin role MODULE 2: Pod Networking Deep Dive 2.1 Pod Network Lifecycle Pod creation workflow CNI ADD/DEL commands IP allocation Route configuration 2.2 Pod-to-Pod Communication Same node communication Cross-node communication Encapsulation techniques (VXLAN, IP-in-IP) 2.3 Pod CIDR & Node CIDR Cluster CIDR allocation Node CIDR assignment Dual-stack (IPv4/IPv6) ...
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ETCD

  What is ETCD? etcd is a distributed, consistent, highly-available key-value store used to store critical cluster data. It is a core component of Kubernetes . etcd port : 2379   Why ETCD Is Important In Kubernetes, etcd stores the entire cluster state , including: Nodes Pods Services ConfigMaps Secrets Deployments RBAC policies If etcd goes down → the cluster control plane stops functioning. ETCD Architecture etcd is based on: Distributed consensus algorithm: Raft Leader–Follower model Strong consistency    High-Level Architecture            ───────────────┐           │   ETCD Leader │           └───────┬───────┘                   │         ┌─────────┴─────────┐         │                   │ ┌───────────────┐  ...
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