iptables + VPn

Quais as regras necessárias para fazer a conecção de duas redes VPN passando por um firewall iptables?

Caro,

Neste caso basta você usar esta regra:

$iptables -t nat -A PREROUTING -i $IF_WAN -p tcp --dport 1723 -j DNAT --to 192.168.0.1:1723

# VPN PPTPD

$iptables -t nat -A PREROUTING -i $IF_WAN -p tcp --dport 1723 -j DNAT --to 192.168.1.1

$iptables -t nat -D PREROUTING -i $IF_WAN -p tcp --dport 1723 -j DNAT --to 192.168.1.1

$iptables -t nat -A PREROUTING -i $IF_WAN -p tcp --dport 1723 -j DNAT --to 192.168.0.1

$iptables -t nat -A PREROUTING -i $IF_WAN -p gre -j DNAT --to 192.168.0.1

$iptables -A INPUT -i eth1 -p tcp -d $IP_WAN --dport 1723 -j ACCEPT

$iptables -A INPUT -i eth1 -p gre -j ACCEPT

$iptables -A FORWARD -p TCP --dport 1723 -j ACCEPT

$iptables -A FORWARD -p 47 -j ACCEPT

IF_WAN = Interface da WAN
IP_WAN = ip da wan

Falou,