ето това сложи в firewall-a
modprobe ip_tables
modprobe iptable_filter
modprobe iptable_nat
modprobe ip_conntrack
modprobe ip_conntrack_ftp
modprobe ip_nat_ftp

iptables -t nat -A POSTROUTING -o eth0 -s 192.168.4.0/24 -j MASQUERADE
iptables -A FORWARD -p udp -s 192.168.4.0/24 --dport 53 -j ACCEPT
iptables -A FORWARD -p tcp -s 192.168.4.0/24 --dport 1732 -j ACCEPT
iptables -A FORWARD -p gre -s 192.168.4.0/24 -j ACCEPT
iptables -A FORWARD -m state --state ESTABLISHED,RELATED -j ACCEPT