Single-monitor is a common way to run Ceph. On top of that, many cluster configurations cause the whole thing to slow to a crawl when a very small minority of nodes go down. Never mind packet loss, bad switches, and other sorts of weird failure mechanisms. Ceph in general is pretty bad at operating in degraded modes. ZFS and systems like Tectonic (FB) and Colossus (Google) do much better when things aren't going perfectly.

Do you know how many administrators CERN has for its Ceph clusters? Google operates Colossus at ~1000x that size with a team of 20-30 SREs (almost all of whom aren't spending their time doing operations).