Study the possibility of generate RBD  images snapshot schedule metrics in the Ceph Prometheus manager module.

The source of the information now is the rbd command to list the recorded schedules:

# rbd --cluster site-a mirror snapshot schedule ls --recursive
We try to see, if it is possible to  generate metrics for every image like:

ceph_rbd_snapshot_schedule  {pool="pool_x", namespace="namespace_y",  image="image_name"} 6
The value of 6 indicates that the snapshot for "image_name" is scheduled every 6 hours.

Things to take into account:

Scalability
This information will be only available for the primary images.