recommendations for different processes/daemons differ considerably.
OSD hosts should have ample data storage in the form of a hard drive or a RAID. Ceph OSDs run the RADOS service, calculate data placement with CRUSH, and maintain their
own copy of the cluster map. Therefore, OSDs should have a reasonable amount of processing power.
Ceph monitors require enough disk space for the cluster map, but usually do not encounter heavy loads. Monitor hosts do not need to be very powerful.
Ceph metadata servers distribute their load. However, metadata servers must be capable of serving their data quickly. Metadata servers should have strong processing capability and plenty of RAM.
