[ceph-users] cephfs flags question

Hi List, In order te reproduce an issue we see on a production cluster (cephFS client: ceph-fuse outperform kernel client by a factor of 5) we would like to have a test cluster to have the same cephfs "flags" as production. However, it's not completely clear how certain features influence the cephfs flags. What I could find in the source code, cephfs_features.h, is that it *seems* to correspond to the Ceph release. For example CEPHFS_FEATURE_NAUTILUS gets a "12" as feature bit. An upgraded (Luminous -> Mimic -> Nautilus) cephfs gives us the following cephfs flags: "1c". A (newly installed) Nautilus cluster gives "10" when new snapshots are not allowed (ceph fs set cephfs allow_new_snaps false) and "12" when new snapshots are allowed (ceph fs set cephfs allow_new_snaps true). We would like to have the test cluster get the "1c" flags and see if we can reproduce the issue. How can we achieve that? Any info on how those cephfs flags are constructed is welcome. Thanks, Gr. Stefan