How to open access from the world to port 9090?

Question

CentOS

Good afternoon,
the first day is familiar with the docker.
I installed Docker on a clean Centos 7, loaded WebAPP and Nginx into it.
On port 80 I see my stub from Nginx. It seems that I have registered the rules for port 9090, but I cannot reach it.
Tell me, maybe you need to somehow forward the port?

Answer 1

Nginx was not needed at all, because it is set by default in my WebApp.

Answer 2

Where did he register what he prescribed what rules? Unclear. I am not a telepath. But I'll try to assume that the problem is in the firewall firewall-cmd --list-port list of ports
firewall-cmd --add-port=9090/tcp this will just add the default port to the public zone but after firewall-cmd --reload the rules will disappear.
firewall-cmd --permanent --add-port=9090/tcp permanent
PS
If you open the 80th port on the firewall. Then, in theory, you can forward 9090 through it even with a closed firewall. This requires the -p switch and the port when you start docker.