In order to be certain your Ceph implementation will be succesfull, there are a number of rules you should follow:

• Use 10G networking as a minimum
• Research and test the correctly sized hardware you wish to use
• Don't use the nobarrier mount option
• Don't configure pools with size=2 or minsize=1
• Don't use consumer SSDs
• Don't use RAID controllers in writeback without battery protection
• Don't use configuration options you don't understand
• Implement some form of change management
• Do carry out power loss testing
• Do have an agreed backup and recovery plan