For what it’s worth, I have a server with two rj45s (and a third for BMC), but I only plugged one of them into my switch. I run anywhere from 2-8 containers/vms on that server and never felt the need to hook up the other jack. I guess there’s probably some contention of running multiple hosts all through that one connection, but typically I don’t really need anything faster than the ~2-400mbps I get with WiFi anyway. So to answer you question, it depends, but I would generally say maybe start with the one and don’t worry about it unless you’re really moving massive amounts of data regularly and saturating your line. You’d also need to consider you’ll need a switch and other network hardware capable of handling that throughout as well if you’re really going to potentially saturate those ports.