i want to add other port in virtualmin, but it's not work

computer’s specifications

ubuntu 14.04 - 5.59
Virtualmin

I am using phpstorm program and hope to use a xdebug plugin

I can’t use it because 9000 port is kept shut

I entered the command as below

iptables -A INPUT -p tcp --dport 9000 -j ACCEPT

it doesn’t work yet

please teach me how to open port in virtualmin (or webmin)