I have a broadband internet connection. I have an wireless modem (Airtel India). I don't have a static ip address. I want to host a ssh/web/ftp server to be visible to the outside world just for testing and learning purpose so I can ask my friend to connect to my current ip address and test. My modem has an admin interface which allows to port forward and open ports.
I set up ssh server as shown and checked if port 22 is open using this website , Port Scan
And port 22 is open. I have an openssh server running and it works if i do,
ssh firstname.lastname@example.org which is my local ip address but doesn't work if i do
ssh email@example.com where 122.xx.xx.xx is my external ip address of my modem which i checked from whatismyipaddress.com.
Since it looks like the port is open, I wonder if there is some setting I need to change in my server config to expose my server. How should I go about solving this?