A Chinese engineer has published a comprehensive upgrade log detailing the process of upgrading a production Kubernetes cluster from v1.31.14 to v1.35.6 and the container runtime containerd from 1.7.27 to 2.3.2. The post covers the entire upgrade flow, including pre-upgrade checks, version compatibility matrices, rollback strategies, and post-upgrade validation. It highlights common pitfalls such as API deprecations, containerd configuration changes, and node drain issues. For DevOps and platform engineers managing self-hosted Kubernetes clusters, this real-world account offers practical insights that go beyond official documentation. The upgrade spanned multiple minor versions, making it a valuable case study for anyone planning a similar multi-step upgrade. The author also shares lessons learned about testing, monitoring, and communication during the upgrade window.
A detailed upgrade log for Kubernetes and containerd in a production cluster, covering version jumps, compatibility issues, and operational best practices.