Last updated: May 23. 2016
As an open-source project, Check_MK has a very transparent development process. As a user, that means you not only have access to the "official" version, but also to the intermediate versions, developer versions and much more. This diversity of options isn't just for show. It gives you the opportunity to decide for yourself if you want to install a new feature or bug fix. This is facilitated by OMD's multi-instance/multi-version concept which allows you to run multiple versions in parallel and switch between them with ease.
The Check_MK version numbers are comprised of multiple numbers and letters that all have an exact meaning.
1. Stable versions
Stable versions have an even last number. Up to the release of the first stable version in a cycle (e.g. 1.2.4) they pass through a very long test phase during which all known bugs are resolved and feedback from the community is incorporated. As a result, patch releases (e.g. 1.2.4p2) appear at irregular intervals. Only bugs are resolved in patch releases; generally no new features are added.
2. Beta versions
Beta versions are pre-release versions of stable versions. New features are only introduced between beta versions in exceptional cases (e.g. new check plugins). The versioning schema is the same as for the stable versions that are being targeted except for the letter b for beta. Beta versions are replaced by stable versions as soon as these are available.
3. GIT-Snapshots of stable versions
To allow you to use a bug fix before the next patch release is available, we publish daily versions of the current stable branch. The version number is made up of the name of the stable version and the date.
4. Innovation versions
The innovation versions provide intermediate stages prior to the next stable version. They contain features and allow their use at an early stage. The final number in the cycle is odd, e.g. 5 in 1.2.5i1. The small i stands for innovation and the final number indicates the sequence number of the innovation version in the current cycle. Innovation versions have, by their nature, not been tested for as long as stable versions.
Innovation versions can also have follow up patch releases. These are identified by p1, p2 etc. and only contain bug fixes.
5. GIT-Snapshots of development branch
These are also called developer versions and show the exact state of the software development at the end of a day. They are created between 0:00 and 3:00 am Central European Time. Developer versions are intermediate versions on the way to the next innovation or stable version. They permit timely deployment of new functions and, above all, serve for evaluation and testing. The stability of these nightly releases varies greatly.The version number is identified solely by the date.