Container Service for Kubernetes (ACK) provides container-centric solutions based on open source Kubernetes. As new Kubernetes versions are released, the list of versions that are supported by ACK also changes. This topic describes how ACK supports different Kubernetes versions.

Release dates and expiry dates

The following table describes the Kubernetes major versions that are supported by ACK clusters and serverless Kubernetes (ASK) clusters.
Version Status Release date Expiration date
v1.24 Released September 2022 September 2024
v1.22 Released December 2021 December 2023
v1.20 Released April 2021 April 2023
v1.18 Expired September 2020 September 2022
v1.16 Expired February 2020 June 2022
v1.14 Expired August 2019 July 2021
v1.12 Expired March 2019 December 2020

Supported versions

Version description

Kubernetes versions follow the semantic versioning scheme in the X.Y.Z format. X is the primary version, Y is the major version, and Z is the patch version. For example, V1.24.2 is the patch version. V1 is the primary version and V1.24 is the major version. For detailed information about Kubernetes versions, see Kubernetes Release Versioning.

Rules

Beginning January 1, 2020, ACK supports only the even-numbered major versions of Kubernetes, such as V1.24, V1.22, and V1.20. These versions will be referred to as major versions in ACK documentation. ACK uses the concept of deprecated versions to refer to versions that are no longer supported by ACK. Deprecated versions are classified into deprecated major versions and deprecated patch versions.
  • Deprecated major versions: ACK supports only three major versions at any given time. Major versions earlier than the earliest supported major version are considered deprecated major versions.
  • Deprecated patch versions: For security reasons, ACK supports only the latest patch versions of each supported major version. All other patch versions are considered deprecated patch versions. Patch versions are updated when patches are released to fix Common Vulnerabilities and Exposures (CVE) vulnerabilities.

The following section describes version skew supported by ACK:

  • Cluster creation

    ACK allows you to create clusters of the two latest major versions. For example, when the latest major version is V1.22, you will be able to create V1.22 and V1.20 clusters. However, when ACK starts to provide support for V1.24, you will no longer be able to create V1.20 clusters.

  • Updates and O&M

    ACK clusters can stably run the latest three major versions of Kubernetes. ACK allows you to update ACK clusters from the two previous major versions to the latest major version. For example, if the latest major version is V1.22, you can update V1.20 and V1.18 clusters. Clusters that use deprecated versions may be unstable and fail cluster updates. We recommend that you update your clusters to the latest major versions at your earliest opportunity.

  • Technical support

    Alibaba Cloud provides technical support for the latest three major versions. Technical support provided by Alibaba Cloud includes consultation, online tutorials, and issue locating and fixing. However, Alibaba Cloud does guarantee the efficacy of support for deprecated versions.

For more information about the versions supported by ACK, see Overview of Kubernetes versions supported by ACK.

Release cycle

  • Alibaba Cloud typically updates the list of major versions supported by ACK every six months.
  • ACK updates its support for new patch versions as soon as the patch versions are released.

Limits

  • Clusters can only be updated sequentially across major versions. You cannot skip major versions. This limit does not apply to patch versions.
  • Support is provided only for the latest patch version. We recommend that you update the earlier patch version of your clusters at your earliest opportunity.