You want to find the external and internal IP addresses of your servers. You are not sure which is which.
The internal IP address is found by issuing one of these commands on Linux:
ip addr show
For Windows, open a command prompt and run this command:
For Linux servers the external IP address is found by running this command (assuming your server has access to the internet):
For Windows open a web browser and go to http://ipchicken.com
If you are using AWS and your server does not have access to the internet, go to the EC2 dashboard. The IP address shown there will be the external IP address.