Ceph

What was the mon protocol change covering (I missed it going in), and don't we need to preserve compatibility across the OSDs regardless of what the monitors are doing?

the new command syntax (json instead of vector<string), and new MonCap encoding. the old protocol won't ever see a >32bit protocol feature bit. unless we backport something weird to cuttlefish...

I'm pretty sure that a pre-fix OSD is going to report that it supports all features to a post-fix OSD — right? That's going to cause issues for stuff like the combined object recovery.