But any tool for looking at Ceph behavior either needs to be tailored to a specific Ceph version, or be able to handle receiving data it doesn't understand without going crazy.
This thread reminds me of a similar thread we had about ceph-volume living inside or outside of the ceph/ceph repo.
Wherever the tool lives, it has to be tailored to a specific Ceph (major) version, e.g. "Luminous" or "Nautilus". As the adjective "major" indicates, from one major version to another, major changes take place.
Having the tool inside the ceph/ceph repo makes this explicit, because each major version of Ceph will then automatically, by the very nature of the thing, have its own major version of said tool. In my experience, when a Ceph-related tool lives "outside" it becomes harder to determine (and enforce) which version of the tool is supposed to work with which version of Ceph.
Nathan
