Kubernetes

Kubernetes, abbreviated as K8s, is an open-source container orchestration platform originally developed at Google and now maintained by the Cloud Native Computing Foundation, automating the deployment, scaling, management, and operations of containerized applications across clusters of machines, providing a declarative API for defining desired application state while the platform continuously works to match actual state to desired state through self-healing, automatic scaling, rolling updates, and traffic routing. The pod abstraction groups one or more containers that share networking and storage, serving as the smallest deployable unit, with deployments managing replica sets for horizontal scaling, stateful sets for ordered deployment of stateful applications, daemon sets for running pods on every node, and jobs and cron jobs for batch and scheduled workloads. The service abstraction provides stable network endpoints and load balancing across pod instances, with ingress controllers managing external HTTP and HTTPS routing, network policies controlling traffic between pods for security isolation, and DNS-based service discovery enabling applications to find each other by name. The storage system supports persistent volumes with dynamic provisioning from cloud provider storage classes, enabling stateful applications like databases to run on the platform with data persistence across pod restarts and rescheduling. The scheduling considers resource requests and limits, node affinity and anti-affinity rules, taints and tolerations, and custom scheduler extensions to place pods optimally across the cluster. The operator pattern enables managing complex stateful applications through custom controllers. The Helm package manager provides templating and lifecycle management. Designed for platform engineers, DevOps teams, cloud architects, and site reliability engineers.