Starting a VM should definitely work, I see in the error message:
"RBD image feature set mismatch. You can disable features unsupported by
the kernel with "rbd feature disable"
Adding "rbd default features = 3" to ceph.conf might help with that.
Thanks! That helped.
https://ovirt.org/develop/release-management/features/storage/cinderlib-i...
means:
Also for Ceph backend, a keyring file and ceph.conf file is needed in
the Engine.
I hat do copy them to all the hosts to start a virtual machine with
attached cinderlib ceph block device.