RBD mirroring is configured by enabling it on a pool basis in a primary and secondary Ceph cluster. There are two modes that can be configured with RBD mirroring depending on what level of data you choose to mirror. Note that the enabled RBD mirroring configuration must be the same per pool on primary and secondary clusters.
- Pool mode: Any image in a pool with journaling enabled is mirrored to the secondary cluster.
- Image mode: Only specifically chosen images with mirroring enabled will be mirrored to the secondary cluster. This requires the image to have mirroring enabled for it.