Week Ending December 14, 2025

Developer News

SIG-etcd has warned users to update to etcd v3.5.26 before upgrading from v3.5 to v3.6, to prevent etcd clusters from reporting “zombie members”.

This will be the last issue of LWKD for 2025. Happy holidays and see you all next year!

Release Schedule

Kubernetes v1.35.0, Timbernetes: World Tree Release is live! Read the release announcment blog post here. The code freeze has been lifted for both kubernetes/kubernetes and kubernetes/website repositories. Big thanks to everyone who contributed to this release!

Kubernetes v1.32.11, which was delayed last week, has now been released.

Other Merges

• Fix nil panic in podcertificatemanager

Subprojects and Dependency Updates

• kind v0.31.0 updates defaults to Kubernetes v1.35.0, refreshes dependencies, and highlights upcoming ecosystem changes. This release reflects Kubernetes 1.35 behavior, including the removal of cgroup v1 support in newer node images, and provides early guidance for a future transition from kubeadm v1beta3 to v1beta4. It also improves IPv6 edge-case detection and updates development and release tooling.
• kubespray v2.29.1 delivers targeted bug fixes for Kubernetes 1.33+ clusters, including Calico apiserver RBAC corrections, improved Cilium load balancer configuration rendering, restored RBAC permissions for Calico host endpoints, and safer removal of external etcd members. The release also refreshes its bundled component matrix, keeping core networking, runtime, and add-on versions in sync.
• vertical-pod-autoscaler Helm chart v0.7.0 updates the chart packaging for Vertical Pod Autoscaler, continuing to support automated CPU and memory recommendation and adjustment workflows for Kubernetes workloads.
• etcd v3.6.7 is a patch release in the 3.6 line that focuses on stability and maintenance updates. Users are advised to review the 3.6 upgrade guide before moving between patch versions, especially in production environments.
• etcd v3.5.26 provides continued maintenance for the 3.5 LTS branch, with fixes and dependency updates aimed at long-lived clusters that have not yet migrated to newer etcd minor versions.
• etcd v3.4.40 maintains the 3.4 release line with stability fixes and is intended for environments that are still pinned to older Kubernetes and etcd combinations.
• prometheus v3.8.1 addresses a Remote Write bug that could cause incorrect response headers and misleading partial error logs, improving reliability for setups that rely on remote write receivers.
• containerd v2.1.6 is a maintenance release for the 2.1 series that updates the bundled runc binary to v1.3.4, refreshes multiple dependencies (including CNI plugins and golang.org/x/* libraries), tightens CRI log redaction, and updates build and CI tooling.
• containerd v1.7.30 continues patch support for the 1.7 branch with fixes in CRI and NRI handling, improved error log redaction, an updated runc v1.3.4 runtime, refreshed CNI plugin installation, and security-focused dependency bumps.

Shoutouts

• Josh Berkus: Thanks to @Christian Baumann for reporting, and then following up on in great detail, an upgrade bug for etcd. With his efforts we were able to figure out a complicated issue and patch it.

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