This section provides answers to common questions about MOSK, and it is designed to help you quickly find the information you need. We have included answers to the most common questions and uncertainties that our users encounter, along with helpful tips and references to step-by-step instructions where required.

The questions with answers in this section are organized by topic. If you cannot find the information you are looking for in this section, search in the whole documentation set. Also, do not hesitate to contact us through the Feedback button. We are always available to answer your questions and provide you with the assistance you need to use our product effectively.

Major and patch releases: updating your cluster

What is the difference between patch and major release versions?

Both major and patch release versions incorporate solutions for security vulnerabilities and known product issues. The primary distinction between these two release types lies in the fact that major release versions introduce new functionalities, whereas patch release versions predominantly offer minor product enhancements.

Patch releases strive to considerably reduce the timeframe for delivering CVE resolutions in images to your deployments, aiding in the mitigation of cyber threats and data breaches.


Major release

Patch release

Version update and upgrade of the major product components including but not limited to OpenStack, Tungsten Fabric, Kubernetes, Ceph, and Stacklight 0

Container runtime changes including Mirantis Container Runtime and containerd updates

Host machine changes including host operating system updates and upgrades, kernel updates, and so on

Changes in public API

Changes in the Container Cloud and MOSK lifecycle management including but not limited to machines, clusters, Ceph OSDs

Patch version bumps of MKE and Kubernetes

Fixes for Common Vulnerabilities and Exposures (CVE) in images

Fixes for known product issues


StackLight subcomponents may be updated during patch releases

Learn more about product releases in MOSK major and patch releases.

What is a product release series?

A product release series is a series of consecutive releases that starts with a major release and includes a number of patch releases built on top of the major release.

For example, the 23.1 series includes the 23.1 major release and 23.1.1, 23.1.2, 23.1.3, and 23.1.4 patch releases.

Is updating to patch release versions mandatory?


Apply patch updates only if you want to receive security fixes as soon as they become available and you are prepared to update your cluster often, approximately once in two weeks.

Otherwise, you can skip patch releases and update only between major releases. Each subsequent major release includes patch release updates of the previous major release.

Can I skip patch releases within a single series?


Moreover, it is technically not possible to update to any intermediate release version if the newer patch version has been released. You can update only to the latest available patch version in the series, which contains the updates from all the preceding versions. For example, if your cluster is running MOSK 23.1 and the latest available patch version is MOSK 23.1.2, you can update to 23.1.2 receiving the product updates from 23.1.1 and 23.1.2 at one go.

Additionally, if between the two major releases you apply at least one patch version belonging to the N series, you have to obtain the last patch release in the series to be able to update to the N+1 major release version.

How do I update to the latest available (current) patch release?

You can update to the current patch release as described in Update a MOSK cluster to a patch release version New.

How do I update between major release versions?

If you skip patch versions and update only between major release versions, follow the Update a MOSK cluster to a major release version procedure.

How do I update to the next major version if I started receiving patches of the previous series?

Firstly, if you started receiving patch updates from the previous release series, update your cluster to the latest patch release in that series as described the Update a MOSK cluster to a patch release version New procedure.

After, follow the Update a MOSK cluster to a major release version procedure to update from the latest patch release in the series to the next major release. It is technically impossible to receive a major release while on any patch release in the previous series other than the last one.