3.9.0

Important

Due to REST API version changes, to upgrade to MKE 3.9 from MKE 3.8.10 or earlier, you must first upgrade to MKE 3.8.11. Following that, you must upgrade to MCR 25.0.12 or later. In addition, upgrading to MKE 3.8.x from MKE 3.7.x can cause your containers to restart, due to the hash calculation rule that was introduced in Kubernetes 1.31. As such, Mirantis recommends that you use the phased in-place cluster upgrade method or the blue-green deployment upgrade method to avoid the simultaneous containers restarts that the automated in-place cluster upgrade method can cause to occur in all nodes.

Release date

Name

Highlights

2026-MAR-24

MKE 3.9.0

Initial MKE 3.9.0 release introducing the following key features and enhancements:

  • Introduction of Envoy Gateway Controller 1.7

  • Introduction of client bundle expiration

  • Component upgrades:

    • Kubernetes 1.34.3

    • Calico 3.31.2

    • Prometheus 3.5.0

    • Docker CLI 29.0.4

    • Docker Client 0.2.1

    • Docker REST API 1.52.0

    • Golang 1.25.7

Important

If you previously disabled Ingress Controller to mitigate vulnerabilities, Mirantis recommends that following upgrade to MKE 3.9.0 you re-enable the component.

In addition, Mirantis recommends that you migrate from Ingress Controller to Envoy Gateway Controller.