One of the key factors when choosing your server models is the number of drives that can be provisioned within each. In the past, servers often could house as few as two drives, requiring external JBOD or RAID arrays for bulk storage, but today the entire front-panel and in some cases much of the rear panel, is available for storage.
Ceph MON, RGW, and MDS servers do not need much local storage, and are often realized with basic 1 U servers, blades, or twin models offering two server modules in a single 1 U chassis. Two or four drives are probably all that you will need. Beware, though, the failure domain: with twin or blade systems, you must take care that the loss or temporary downtime of a chassis ...
