Container Service for Kubernetes (ACK) provides container-centric solutions based on open source Kubernetes. As new Kubernetes versions are released, the list of Kubernetes versions supported by ACK also changes. New Kubernetes versions will be added to the list and outdated Kubernetes versions will be discontinued. This topic describes how ACK supports different Kubernetes versions, including the version list update cycle, the support policies, and the risks of using outdated Kubernetes versions.
Release history
The following table describes the Kubernetes versions that are supported by ACK clusters and ACK Serverless clusters.
Version | Status | Release date (ACK) | Discontinue date (ACK) |
Released | October 2023 | October 2025 | |
Released | April 2023 | April 2025 | |
Released | September 2022 | September 2024 | |
Discontinued | December 2021 | October 2023 | |
Discontinued | April 2021 | April 2023 | |
Discontinued | September 2020 | September 2022 | |
Discontinued | February 2020 | June 2022 | |
v1.14 | Discontinued | August 2019 | July 2021 |
Discontinued | March 2019 | December 2020 |
Version updates
Starting from January 1, 2020, ACK supports only even-numbered Kubernetes minor versions, such as 1.24, 1.26, and 1.28. ACK updates the list of supported minor versions every six months. ACK updates its support for new patch versions after the patch versions are released.
Version description
The Kubernetes versions supported by ACK follow the semantic versioning scheme in the x.y.z-aliyun.n format. x.y.z is the open source Kubernetes version. x is the major version, y is the minor version, z is the patch version, and n is the ACK patch version. For example, version 1.28.3-aliyun.1 is based on open source Kubernetes 1.28.3. For more information about Kubernetes versions, see Kubernetes Release Versioning.
Rules for supporting Kubernetes versions
Cluster creation
ACK allows you to create clusters of the latest three even-numbered minor versions. For example, if the latest minor version is 1.28, you can create clusters of 1.24, 1.26, and 1.28. When ACK starts to support 1.28, 1.22 is discontinued and you can no longer create clusters of 1.22. In addition, the outdated patch version is no longer available.
Cluster update
ACK allows you to update ACK clusters from a minor version to the following minor version. You cannot skip minor versions when you update ACK clusters or roll back your ACK clusters to an earlier version. For example, if your cluster version is 1.24 and you want to update the cluster to 1.28, you need to complete the update in two steps. You need to update the cluster to 1.26 and then update it to 1.28.
For patch versions, ACK allows you to update an ACK cluster only to the latest patch version. You cannot update your cluster to outdated patch versions.
Technical support
Alibaba Cloud provides technical support for the latest three even-numbered minor versions. Technical support provided by Alibaba Cloud includes consultation, online tutorials, and troubleshooting.
Outdated Kubernetes versions
Security and stability risks exist in outdated Kubernetes versions. We recommend that you update your clusters that use outdated Kubernetes versions at the earliest opportunity. For more information about cluster updates, see Update an ACK cluster.
ACK provides the following support policies for clusters that run outdated Kubernetes versions:
Stop releasing new features
Stop fixing feature and security issues
Provide limited technical support
ACK does not guarantee that technical support can be provided at the first time except for issues related to cluster and component updates.
Reserve the right to force the clusters that run outdated Kubernetes versions to update
For availability and security purposes, after the Kubernetes version of a cluster becomes outdated, ACK forces the cluster to update to the earliest Kubernetes version supported by ACK. For example, if your cluster version is 1.20 and ACK supports Kubernetes versions 1.24, 1.26, and 1.28, ACK forces your cluster to update to 1.24.
ACK will send notifications to you by text messages, emails, or internal messages at least one month before the update. Pay close attention to the notifications and prepare for the update in advance.
References
We recommend that you learn the updates and usage notes of each Kubernetes version before you update your cluster. For more information, see Update an ACK cluster.