linkerd/linkerd2 stable-2.8.0

on GitHub

stable-2.8.0

This release introduces new a multi-cluster extension to Linkerd, allowing it
to establish connections across Kubernetes clusters that are secure,
transparent to the application, and work with any network topology.

• The CLI has a new set of linkerd multicluster sub-commands that provide
  tooling to create the resources needed to discover services across
  Kubernetes clusters.
• The linkerd multicluster gateways command exposes gateway-specific
  telemetry to supplement the existing stat and tap commands.
• The Linkerd-provided Grafana instance remains enabled by default, but it can
  now be disabled. When it is disabled, the Linkerd dashboard can be
  configured to link to an alternate, externally-managed Grafana instance.
• Jaeger & OpenCensus are configurable as an add-on; and the
  proxy has been improved to emit spans with labels that reflect its pod's
  metadata.
• The linkerd-cni component has been promoted from experimental to
  stable.
• linkerd profile --open-api now honors the x-linkerd-retryable and
  x-linkerd-timeout OpenAPI annotations.
• The Helm chart continues to become more flexible and modular, with new
  Prometheus configuration options. More information is available in the
  Helm chart README.
• gRPC stream error handling has been improved so that transport errors
  are indicated to the client with a grpc-status: UNAVAILABLE trailer.
• The proxy's memory footprint could grow significantly when
  server-speaks-first-protocol connections hit the proxy. Now, a timeout is
  in place to prevent these connections from consuming resources.
• After benchmarking the proxy in high-concurrency situations, the inbound
  proxy has been improved to reduce contention, improving latency and
  reducing spurious timeouts.
• The proxy could fail requests to services that had only 1 request every 60
  seconds. This race condition has been eliminated.
• Finally, users reported that ingress misconfigurations could cause the proxy
  to consume an entire CPU which could lead to timeouts. The proxy now
  attempts to prevent the most common traffic-loop scenarios to protect against
  this.

NOTE: Linkerd's multicluster extension does not yet work on Amazon
EKS. We expect to follow this release with a stable-2.8.1 to address this
issue. Follow #4582 for updates.

This release includes changes from a massive list of contributors. A special
thank-you to everyone who helped make this release possible: @aliariff,
@amariampolskiy, @arminbuerkle, @ArthurSens, @christianhuening,
@christyjacob4, @cypherfox, @daxmc99, @dr0pdb, @drholmie, @hydeenoble,
@joakimr-axis, @jpresky, @kohsheen1234, @lewiscowper, @lundbird, @matei207,
@mayankshah1607, @mmiller1, @naseemkullah, @sannimichaelse, & @supra08.