Hi: A common use case for downgrade is rolling back from problematic upgrades. Mesos promises compatibility between any 1.x and 1.y versions of masters/agents as long as new features are not used. However, currently there is no easy way to tell whether any “new” features are being used. And any incompatible downgrade would silently result in undefined behavior instead of failsafe. This is not ideal.
We want to help operators to make informed downgrade decisions and to take correct actions (e.g. deactivate the use of certain new features) if necessary. To this end, we propose adding minimum component capability. Please checkout the doc below for more details. Feel free to comment in the doc! Thanks! JIRA: *MESOS-8878 <https://issues.apache.org/jira/browse/MESOS-8878>* Design proposal <https://docs.google.com/document/d/1HAfd05725aabKzR-sYNiZ28IchMnw60m7xv1VviHfIg/edit#> -Meng
