I love Ceph to pieces! I don’t love it’s docs that much though, and I find the multi-level subcommands unintuitive at times. Quick, is it "ceph pg query x.y" or "ceph pg x.y query"? There’s some good docs out there, but to me they feel scattered and it’s always taking me some time to get there.
To cache some of that info I’ve put together a small Ceph cheat sheet for common invocations, maybe someone else finds that useful as well. Feedback is of course very welcome (mail or twitter @petersabaini).