Week Ending May 25, 2025

Developer News

The Program Committee is now accepting applications for the Maintainer Summit North America 2025. Share your interest in joining the committee before Monday, July 7th.

Release Schedule

Next Deadline: PRR Freeze, June 12th

The Release Cycle for 1.34 has started, and the release team is actively collecting enhancements. SIG Leads should discuss enhancements and add the lead-opted-in label for KEPs going into v1.34.

Featured PRs

131842: Add metrics for compatibility version

This PR adds alpha metrics for binary, emulation, and minimum compatibility versions in componentGlobalsRegistry, exposed via Prometheus in kube-apiserver, scheduler, and controller-manager for observability of version negotiation. It introduces an AddMetrics method that publishes the binary version, emulation version, and minimum compatibility version of each component as Prometheus gauge metrics. Users can now monitor version negotiation for kube-apiserver, scheduler, and controller-manager using these metrics.

128748: feat: introduce pInfo.UnschedulableCount to make the backoff calculation more appropriate

This PR updates the scheduler to separate scheduling failures caused by plugin rejections from those caused by internal errors. It introduces UnschedulableCount to track only plugin-based rejections, ensuring that transient errors like API failures or network issues do not increase backoff time unfairly. This change improves scheduling fairness and responsiveness under cluster instability.

129983: feature(scheduler): Customizable pod selection and ordering in DefaultPreemption plugin

This PR introduces support for customizing pod selection and ordering in the DefaultPreemption plugin; It adds optional EligiblePods and OrderedPods function hooks, allowing scheduler integrations to override the default behavior without reimplementing the plugin. This enables more flexible preemption strategies while maintaining the existing plugin interface.

131677: (Kubeadm): Add support for ECDSA-P384 encryption algorithm

This PR adds support for the EncryptionAlgorithmECDSAP384 in kubeadm API types; Users can now choose ECDSA-P384 for generating PKI assets like CA and component certificates during kubeadm init; Implemented key generation logic for ECDSA P-384 keys in pkiutil (using elliptic.P384()). This ensures the algorithm is handled correctly across pkiutil and cluster configuration paths.

KEP of the Week

KEP 4369: Allow almost all printable ASCII characters in environment variables

This enhancement allowed all printable ASCII characters (with ASCII codes 32–126), except "=", to be used in environment variable names. Previously, Kubernetes imposed restrictions that could prevent certain applications from functioning as intended, especially when users couldn’t control the variable names. By lifting these constraints, the change improved compatibility with a broader range of applications and removed an adoption barrier, aligning Kubernetes behaviour more closely with real-world usage patterns

This KEP is tracked for beta in v1.34.

Other Merges

automatic_reloads of authz config metrics to beta
Pod backoff to be completely skipped when PodMaxBackoffDuration kube-scheduler option is set to zero
Shorthand for –output flag in kubectl explain which was accidentally deleted has been added back
Kubernetes is now built using Go 1.24.3
References to group resource in metrics unified
e2e: Shadowed error fixed in reboot test
Filter integration tests added for NodeAffinity plugin
AuthenticationConfiguration type has been promoted to apiserver.config.k8s.io/v1
Volumes on nodes to not be expanded if controller expansion is finished

Promotions

QueueingHint to GA
kuberc to beta

Version Updates

Subprojects and Dependency Updates

minikube v1.36.0 delivers significantly faster vfkit networking on macOS with the --network vmnet-shared option, supports Kubernetes v1.33.1, enables addon configuration via a dedicated config file, and includes additional improvements
vertical-pod-autoscaler v1.4.0 is out, with alpha support for in-place pod resource updates via the InPlaceOrRecreate Feature Gate, improved resource tracking from pod status, options for global maximum resource limits, and a set of bug fixes and dependency updates
kubespray v2.28.0 is out with a bunch of version updates. Krew installation support is removed.

Shoutouts

No shoutouts this week. Want to thank someone for special efforts to improve Kubernetes? Tag them in the #shoutouts channel.

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