Week Ending December 13, 2020

Developer News

ICYMI, Kubernetes 1.20 has been released. This particular release has 42 major enhancements, making it the most featureful release in a while, and probably the most disruptive as well. Maybe use the holidays for testing instead of deploying it on Christmas Eve. Just a tip.

The chairs of the Component Standard WG are retiring and are looking for new leaders for that WG.

Release Schedule

Next Deadline: 1.21 cycle begins, January 5th

We are currently in the limbo period between the release of 1.20 and the start of official 1.21 development, otherwise known as “packaging up 1.20.1”. Expect an announcement of the start of 1.21 after New Year’s, and even consider being a release team shadow.

1.19.5, 1.18.13, 1.17.15, were released last week. Primary fixes are keeping app pods from disrupting the kubelet on Windows, and fixing OOM issue on Linux kernel 5.1+.

Featured PRs

#96311: Convert users of old failure-domain labels to new

A good reminder and example of updating code using the old failure-domain.beta.kubernetes.io labels, this PR switches a lot of systems over to the newer topology.kubernetes.io equivalents. If you’ve been putting off a similar update in your in-tree code or external automation, now is a great time to start!

#96668: ignore update pod without new image in alwayspullimages admission controller

If you use the AlwaysPullImages admission controller, this should ease switching pains when enabling it. Previously all pods would have to be recreated due to imagePullPolicy being an immutable field, now updates to existing pods created before enabling the admission plugin will still be updatable except to change their image.

#89688: Added ‘No resources found’ message to logs command

To improve usability by humans, kubectl logs -l will now display an error banner if no pods match the requested label selector. If you use commands like that in automation, notably in CI jobs where the pods don’t always exist yet, be sure to check for compatibility.

Other Merges

Carlos Panato gives kubectl a Brazillian translation
Auto-detect global ip addresses attached to the loopback interface on nodes, and support BGP Unnumbered
APIserver’s locking lease in etcd becomes configurable
Results of kubectl logs --tail # are now repeatable
No more panic in the kubelet if some status fields are missing
Add AcceleratorStats to cri_stats_provider (backported fix)
Don’t corrupt Fiberchannel volumes on disconnect
Cloud provider routes stop depending on --allocate-node-cidrs by side effect, are set only by --configure-cloud-routes.

Deprecated

Several deprecated scheduler metrics are being removed in 1.21.
Service.topologyKeys is deprecated in 1.21, to be replaced by Topology Aware Subsetting
Setting service.beta.kubernetes.io/azure-load-balancer-mixed-protocols is removed

Version Updates

cadvisor to v0.38.6 in 1.21 and 1.20, to v0.37.3 in 1.19
Cluster Autoscaler to v1.20.0
etcd to v3.4.13 in kubeadm deployments of 1.19 and 1.20

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