Ceph

1. Image spec
   [root@localhost ~]# rbd info test/v2image
   rbd image 'v2image':
   size 10240 MB in 2560 objects
   order 22 (4096 kB objects)
   block_name_prefix: rbd_data.37826b8b4567
   format: 2
   features: layering, exclusive-lock, object-map, fast-diff, deep-flatten
   flags:

1. Kernel
   [root@localhost ~]# uname -r
   4.9.6-100.fc24.x86_64

1. Try to map image to local
   [root@localhost ~]# rbd map test/v2image
   2017-02-06 11:16:18.319002 7f66966821c0 -1 auth: unable to find a keyring on /etc/ceph/ceph.client.admin.keyring,/etc/ceph/ceph.keyring,/etc/ceph/keyring,/etc/ceph/keyring.bin: (2) No such file or directory
   rbd: sysfs write failed
   RBD image feature set mismatch. You can disable features unsupported by the kernel with "rbd feature disable".
   In some cases useful info is found in syslog - try "dmesg | tail" or so.
   rbd: map failed: (6) No such device or address

1. Disable v2 features
   [root@localhost ~]# rbd feature disable test/v2image deep-flatten
   [root@localhost ~]# rbd feature disable test/v2image fast-diff
   [root@localhost ~]# rbd feature disable test/v2image object-map
   [root@localhost ~]# rbd feature disable test/v2image exclusive-lock

1. Try to map image to local
   [root@localhost ~]# rbd map test/v2image
   2017-02-06 11:18:43.822701 7f8914b011c0 -1 auth: unable to find a keyring on /etc/ceph/ceph.client.admin.keyring,/etc/ceph/ceph.keyring,/etc/ceph/keyring,/etc/ceph/keyring.bin: (2) No such file or directory
   /dev/rbd0

1. Result
   [root@localhost ~]# rbd showmapped
   id pool image snap device
   0 test v2image - /dev/rbd0

Any missing bits?