Kubernetes Cluster Upgrade Strategy: From Planning to Zero-Downtime Execution
Overview Kubernetes releases three minor versions per year, each with a support cycle of approximately 14 months. This means production clusters need to be upgraded roughly every 6-12 months. Cluster upgrades are one of the most sensitive operations in K8s operations — you must keep pace with the community for security patches and new features while ensuring zero downtime and zero failures during the upgrade process. This article covers the complete methodology of Kubernetes cluster upgrades, from version strategy formulation, pre-upgrade preparation, upgrade execution, blue-green/canary strategies, rollback mechanisms, to production-grade best practices....