How to access the keycloak server (private IP) with domain name - networking

Question

I have configured the keycloak server. I'm able to access the server with private IP address (192.X.X.X).
When I'm mapping this IP address to the external domain name, the keycloak page is not opened.
Moreover, I'm trying to run server as both format - such as
-b=192.x.x.x
-b=0.0.0.0.
None of them is working.
What is the problem and how can I resolve it?

Answer 1

The problem there is that private IP addresses (the ones in ranges below) are not routeable on the internet. You have to use public IP address to be access from the internet (out of domain).
Private ranges:
10.0.0.0 - 10.255.255.255
172.16.0.0 - 172.31.255.255
192.168.0.0 - 192.168.255.255
So actually what happens, when You set this IP address to the DNS server (set domain example.com to change into 192.168.1.1), it will correctly translate. However after that, the routers will drop the traffic, as it cannot go over the internet.
More on topic for example here: https://www.lifewire.com/what-is-a-private-ip-address-2625970
Solution:
consider this fake public IP address as yours 88.123.123.123, domain example.com
1) Get the server a public IP address so it can be reached from the internet, set forwarding-protocol on Your router at the company/home, e.g. transfer rule:
<from public int> -> <to private int>
--------------------------------------
88.123.123.123:80 -> 192.168.1.1:80 //Port for HTTP traffic
88.123.123.123:443 -> 192.168.1.1:443 //Port for HTTPS traffic
2) Set up listening of Your server on 0.0.0.0 and 192.168.1.1 should work just fine.
3) Last, set up the DNS translation on the DNS server.
example.com -> 88.123.123.123
Example of topology:
There is public IP 24.65.45.89 and the IP of the server 10.20.0.2: