1.
MC will look at your network adapters to find local IP and MAC-addresses associated with your computer. The MAC address make it possible to wake your computer while sleeping, and the IP address is needed for the actual communication with your copy of MC.
In addition, your external IP-address is added in case you want to access your computer from outside your home network. (Please note that external connections require additional setup on your router)
I won't be trying manual connections via IP/Port as that has implications for Wake on LAN functionality. My server is set up to sleep rather than being always on.
I cannot connect to either computer by using the Global ipaddress.
It appears I must use the access key.
Are your two servers up and running, or asleep when you are testing? If not, you have to use the Access Key, since it stores the MAC address of your server, which is required to be able to issue Wake On LAN requests.
Why does jremote offer the ability to connect via global ipaddress?
Because if your servers are up and running, awake, you should be able to access them from outside your LAN using just the External IP Address and the Port number.
You should do all your initial testing with both servers up and running, awake. The issues to look at if you can't connect are the router firewall, where the ports need to be open and
forwarded to the correct server, and any
software firewall on the servers that need to allow the connection.
So in your example above, where your External IP Address was 134.23.11.23, and the port number you had configured MC to respond to on Server1 is 52198, assuming for example that the target Server1 LAN IP was 192.168.1.85, you would need to forward port 52198 in your router to 192.168.1.85. To access this Server1 you would point JRemote at 134.23.11.23:52198.
Then if on Server2 MC was set to respond to port 52199, and Server2 had a LAN IP Address of 192.168.1.94, then you would forward port 52199 in your router to 192.168.1.94. To access this Server2 you would point JRemote at 134.23.11.23:52199.
I assume that you have configured the two different port MC should use under "Options > Media Network > Advanced > TCP Port" on each server? If you haven't, 52199 is the default port, and that would explain why one server is responding and the other isn't.
Once you have all that working you can try connecting to each server while it is asleep using their access keys. I would be interested to know if that works, waking the server and connecting to MC. Theoretically, it should.