Kubernetes & Cloud-Native Orchestration - Production Essentials

A strongly consistent, distributed key-value store used as Kubernetes' primary datastore. It stores all cluster state, configuration data, and metadata. Reliable backups of etcd are critical for cluster disaster recovery.

The central management hub of the Kubernetes control plane. It exposes the Kubernetes API (RESTful), validates and processes requests, and serves as the sole component that directly communicates with etcd.

The control plane component that monitors newly created Pods without assigned nodes and selects the optimal worker node for them to run on based on resource requirements, constraints, affinity rules, and taints/tolerations.

A control plane daemon that embeds core controller loops (such as the DeploymentController, NodeController, and ReplicaSetController). It continuously monitors cluster state via kube-apiserver and drives current state toward the desired state.

The primary agent running on every worker node. It registers the node with the cluster, watches kube-apiserver for PodSpecs assigned to its node, and ensures the specified containers are running and healthy via the Container Runtime.

A network proxy that runs on each worker node, maintaining network rules (typically using iptables or IPVS). It implements the Kubernetes Service abstraction by reflecting local networking and routing traffic to appropriate backend Pods.

The smallest deployable computing unit in Kubernetes. A Pod represents a single instance of a running process and can contain one or more containers that share the same network namespace, IP address, and storage volumes.

A declarative workload resource that manages stateless Pods via ReplicaSets. It provides declarative updates, rolling upgrades, easy rollbacks, and automated scaling for application pods.