Forward traffic from port 80 to port 8080 on same server:
$ firewall-cmd --zone=external --add-forward-port=port=80:proto=tcp:toport=8080
Forward traffic from port 80 to port 80 on other server:
$ firewall-cmd --zone=external --add-forward-port=port=80:proto=tcp:toaddr=10.10.10.2
Forward traffic from port 80 to other server 10.10.10.2 and port 8080:
$ firewall-cmd --zone=external --add-forward-port=port=80:proto=tcp:toport=8080:toaddr=10.10.10.2