Cephalocon 2024

This session will cover overall ceph manager design and operational aspects of the ceph MGR daemon. We will begin by giving an introduction to the MGR architecture, move on to discussing functionality of the mgr DaemonServer, mgr client, python module registry, base mgr module, and loading and unloading of the mgr modules. We will then move on to discuss module debugging, an example of GIL deadlock debugging, and how to troubleshoot MGR bugs and plugin issues. Finally, we discuss new features including tracking mgr ops and further improvements planned for future releases.

The scrub ‘restrictions overrides’ matrix: Scrubs can be triggered by multiple conditions, with each trigger resulting in a specific set of scrub-session behaviors and a specific set of limitations / restrictions that apply or are overridden (operator-initiated scrub, for example, are allowed to run on whatever day of the week or hour, regardless of configuration). The matrix of ‘scrub-type to restrictions’ was never fully nor consistently documented. Starting with the ‘Reef’, through ‘Squid’, and - hopefully - finalized in ‘Tentacles’ - we are working on clarifying, documenting and implementing the desired behaviors - the desired matrix. I will present, with the goal of receiving feedback from the Ceph community, what was already released with Squid, and - more important - what changes to this matrix are planned for Tentacles. For the community, this would be a great opportunity to influence the fine details of what will be part of the next Ceph release.