Linkerd Edge Release Roundup: January 2025

Welcome to the January 2025 Edge Release Roundup post, where we dive into the most recent edge releases to help keep everyone up to date on the latest and greatest! In this month’s Roundup, we’re closing the books on edge releases from 2024, culminating in the release of Linkerd 2.17.0 – as such, we have several releases with several new features to cover here!

How to give feedback

Edge releases are a snapshot of our current development work on main; by definition, they always have the most recent features but they may have incomplete features, features that end up getting rolled back later, or (like all software) even bugs. That said, edge releases are intended for production use, and go through a rigorous set of automated and manual tests before being released.

We would be delighted to hear how these releases work out for you! You can open a GitHub issue or discussion, join us on Slack, or visit the Buoyant Linkerd Forum – all are great ways to reach us.

Community contributions

We couldn’t do what we do without the Linkerd community, and this batch of releases is definitely no exception. Huge thanks to Brandon Ros, Derek Brown, and Micah See for their contributions! You’ll find more information about all of these contributions in the release-by-release details below.

Recommendations and breaking changes

If you’re looking at any of the eight(!!) edge releases in our list this month, candidly you should really just go straight for edge-24.11.8 – that’s the latest and greatest, corresponding to Linkerd 2.17.0, so there’s no reason you wouldn’t choose that one. However, most of these releases are recommended for general use, and there are no breaking changes in any of them, so if you want to try an older one, go for it!

The two exceptions here are:

We don’t recommend edge-24.11.6, since edge-24.11.7 came out literally the same day with three nice-to-have fixes.
We also don’t recommend edge-24.11.2, since edge-24.11.3 includes an important fix for the linkerd diagnostics endpoints command.

The releases

November’s releases are all about landing the features that make up Linkerd 2.17.0. Of course, each edge release includes many dependency updates which we won’t list here, but you can find them in the release notes for each release.

edge-24.11.8 (November 26, 2024)

edge-24.11.8 corresponds to Linkerd 2.17.0.

This release closes out Linkerd 2.17 by updating dependencies to change Linkerd’s logic around Kubernetes leases, in order to make sure that patches don’t get stuck indefinitely.

edge-24.11.7 (November 25, 2024)

This release removes the initial delay for the policy controller, allowing for faster control-plane startups. It also quietens the policy controller’s reconciliation logs and adds logging to make it clear which policy-controller pod is responsible for updating statuses.

edge-24.11.6 (November 25, 2024)

edge-24.11.6 is NOT RECOMMENDED; it has been superseded by edge-24.11.7.

edge-24.11.7 was released the same day as edge-24.11.6, superseding it.

edge-24.11.5 (November 22, 2024)

In this release, the proxy emits new request_frame_size and response_frame_size metrics with information about TCP frame distributions, correctly accounts for closed connections in route metrics, and fixes a (rare) panic for resources in which managedFields has no timestamp. Additionally, linkerd check checks to be sure that your Link resources match your CLI version, keywords in docker build now use correct cases (thanks, Derek Brown!). Finally, for this release we started testing Linkerd on Kubernetes 1.31.

edge-24.11.4 (November 19, 2024)

This release fixes a bug (issue 13327) where Linkerd could constantly re-update the status clause of HTTPRoute if another Gateway API controller was present in the system (thanks Derek Brown!), ensures that all of the proxy-injector’s logs are valid JSON when JSON logging is enabled (thanks, Micah See!), and cleans up HTTPRoute validation to make sure that if a backendRef is a Service, it must have a valid port.

edge-24.11.3 (November 14, 2024)

This release brings local rate limiting to Linkerd! Using the new HTTPLocalRateLimitPolicy resource, you can attach rate limits to Servers to protect workloads from being overwhelmed by excessive traffic. Additionally, it improves metrics for TCPRoute and TLSRoute egress control, correctly handles the case where a Route type changes parents (fixing [issue #13280]), allows linkerd diagnostics endpoints to correctly handle workloads with multiple endpoints, and removes unneeded references to linkerd-base from the linkerd-control-plane chart README (thanks, Brandon Ros!).

edge-24.11.2 (November 8, 2024)

edge-24.11.2 is NOT RECOMMENDED, since linkerd diagnostics endpoints may not correctly show all endpoints for federated Services. We recommend using edge-24.11.3 instead.

This release brings federated Services to Linkerd multicluster setups! Every federated Service appears exactly the same from every cluster (rather than having names like svc-cluster) and Linkerd seamlessly handles everything to gather the relevant endpoints from all clusters, without requiring application changes or HTTPRoute configuration.

edge-24.11.1 (November 7, 2024)

This release brings egress monitoring and control to Linkerd! Using the new EgressNetwork CRD as a parentRef for an HTTPRoute, GRPCRoute, TCPRoute, or TLSRoute, you can see which workloads are making egress calls and set policy on what’s allowed and what isn’t.

Installing the latest edge release

Installing the latest edge release needs just a single command.

curl --proto '=https' --tlsv1.2 -sSfL https://run.linkerd.io/install-edge | sh

You can also install edge releases with Helm.

Linkerd is for everyone

Linkerd is a graduated project of the Cloud Native Computing Foundation. Linkerd is committed to open governance. If you have feature requests, questions, or comments, we’d love to have you join our rapidly-growing community! Linkerd is hosted on GitHub, and we have a thriving community on Slack, Twitter, and in mailing lists. Come and join the fun!

Linkerd generally does new edge releases weekly; watch this space to keep up-to-date. Feedback on this blog series is welcome! Just ping @flynn on the Linkerd Slack.