2018 Unity Networking Stack
Take a look at the current issues.
If you prefer to use the terminal for the server build, make sure when building the server inside Unity to check off "Server Build" to get descriptive output and allow input such as Ctrl + C to stop the server.
"Server.exe" -batchmode -nographics
Commands
exit
stop
start
restart
say
kick
Nothing much to say about this right now.
Note that the connectionId is NOT from the receiving client but instead from the current client.
NetworkEventType type = NetworkTransport.Receive(out int recHostId, out int connectionId, out int channelId, recBuffer, recBuffer.Length, out int dataSize, out error);