Kubernetes 1.21 – What's new?

Kubernetes 1.21 introduces a series of enhancements and feature graduations aimed at improving performance, security, and flexibility. The update includes 50 enhancements, with 15 features reaching stable status, 14 existing features receiving improvements, and 19 new features being introduced. Key highlights include the introduction of a Memory Manager to optimize application performance, enhanced scheduling capabilities with nominated nodes and pod affinity selectors, and new downscaling strategies for ReplicaSets. The update also marks the deprecation of Pod Security Policies due to their limitations, with complete removal expected by Kubernetes 1.25. Additionally, new network policy configurations, metrics stability enhancements, and storage capacity tracking have been introduced, alongside advancements in authentication and API machinery. Kubernetes 1.21 continues to evolve with features that cater to a broader range of applications and use cases, enhancing the platform's scalability and manageability.