Under your Security settings have you enabled "allow incoming connections?" I'm currently using the same setup (LAN via Thunderbolt adapter) without issue. However, I do remember having to allow the incoming connections in my security preference. Also, once you have everything connected go into your OSX Network settings that displays all the currently running networks. There should be a spot indicating ethernet activity. This will allow you to help troubleshoot the problem to see if there's any communication between the hub and the CPU.