I installed and started apache 2.2.31 on Linux Ubuntu 15.10. When i enter my loopback id (127.0.0.1) in my browser, the correct message ("It works") appears, but, when i enter my site ip address (71.187.235.187) in the browser, I receive the message: "Firefox can't establish a connection to the server at 71.187.235.187."
Note that the directive "Listen" is set to 80.
The following commands and responses may be relevant:
root@pegasus:/proc# nc -zv 127.0.0.1 80 // Trying to access the loopback ID
Connection to 127.0.0.1 80 port [tcp/http] succeeded!
root@pegasus:/proc# nc -zv 71.187.235.187 80 // Trying to access the site ID
nc: connect to 71.187.235.187 port 80 (tcp) failed: No route to host