I fixed it in PORTS TRIGGER menu of my router. Thanks you anyway

I have a weird problem related with (i think) my cable-router and my configured vhosts in Apache2.

The point is I can't access from outside of my LAN to any of my configured vhosts if I set the http port of Apache to 80 and i add a NAT rule for it. Otherwise, if I set my Apache port to 81 (or any else) with its respective NAT rule on my router it works.

My router is an ARRIS TG952S and I am using Apache/2.2.22 (Debian)

ports.conf

NameVirtualHost *:80
Listen 80

vhost1.mydomain.net.conf

<VirtualHost *:80>
    ServerAdmin webmaster@localhost
    ServerName vhost1.mydomain.net
    ServerAlias vhost1.mydomain.net www.vhost1.mydomain.net

vhost2.mydomain.net.conf

<VirtualHost *:80>
    ServerAdmin webmaster@localhost
    ServerName vhost2.mydomain.net
    ServerAlias vhost2.mydomain.net www.vhost2.mydomain.net

DNS records (using FreeDNS) are:

mydomain.net        --> pointing to another server
vhost1.mydomain.net --> pointing to my server
vhost2.mydomain.net --> pointing to my server

iptables -L -n

Chain INPUT (policy ACCEPT)
target     prot opt source               destination         
fail2ban-apache-noscript  tcp  --  0.0.0.0/0            0.0.0.0/0            multiport dports 80,443
fail2ban-apache  tcp  --  0.0.0.0/0            0.0.0.0/0            multiport dports 80,443
fail2ban-ssh  tcp  --  0.0.0.0/0            0.0.0.0/0            multiport dports 22

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination         

Chain fail2ban-apache (1 references)
target     prot opt source               destination         
RETURN     all  --  0.0.0.0/0            0.0.0.0/0           

Chain fail2ban-apache-noscript (1 references)
target     prot opt source               destination         
RETURN     all  --  0.0.0.0/0            0.0.0.0/0           

Chain fail2ban-ssh (1 references)
target     prot opt source               destination         
RETURN     all  --  0.0.0.0/0            0.0.0.0/0 

Thanks you