Ik heb 2 linux server 1 dient voor firewall, en de andere dient als VPN server. Intern kan ik inbellen op de vpn server. Met een windows bak. (dit betekend dat GRE goed zit op die bak). Als ik het via de extern manier probeert krijg ik een foutmelding op mijn VPN server in mijn /var/log/message
Jul 3 15:52:31 vpn pppd[7791]: pppd 2.4.1 started by root, uid 0
Jul 3 15:52:31 vpn pppd[7791]: Using interface ppp0
Jul 3 15:52:31 vpn pppd[7791]: Connect: ppp0 <--> /dev/pts/2
Jul 3 15:52:31 cpn pptpd[7790]: GRE: read(fd=6,buffer=8055c60,len=8260) from network failed: status = -1 error = Protocol not available
Jul 3 15:52:31 vpn pptpd[7790]: CTRL: GRE-tunnel has collapsed (GRE read or PTY write failed (gre,pty)=(6,5))
Jul 3 15:52:31 vpn pptpd[7790]: CTRL: Client 192.168.0.100 control connection finished
Dit is voor de portforwarding
iptables -A PREROUTING -t nat -p tcp -d externIP --dport 1723 -j DNAT --to 192.168.0.10:1723
iptables -A POSTROUTING -t nat -o eth1 -p tcp -s 192.168.0.0/24 -d 192.168.0.10 --dport 1723 -j MASQUERADE
iptables -A INPUT -p 47 -j ACCEPT
iptables -A OUTPUT -p 47 -j ACCEPT
De firewall = RH7.3
VPN = RH9
Jul 3 15:52:31 vpn pppd[7791]: pppd 2.4.1 started by root, uid 0
Jul 3 15:52:31 vpn pppd[7791]: Using interface ppp0
Jul 3 15:52:31 vpn pppd[7791]: Connect: ppp0 <--> /dev/pts/2
Jul 3 15:52:31 cpn pptpd[7790]: GRE: read(fd=6,buffer=8055c60,len=8260) from network failed: status = -1 error = Protocol not available
Jul 3 15:52:31 vpn pptpd[7790]: CTRL: GRE-tunnel has collapsed (GRE read or PTY write failed (gre,pty)=(6,5))
Jul 3 15:52:31 vpn pptpd[7790]: CTRL: Client 192.168.0.100 control connection finished
Dit is voor de portforwarding
iptables -A PREROUTING -t nat -p tcp -d externIP --dport 1723 -j DNAT --to 192.168.0.10:1723
iptables -A POSTROUTING -t nat -o eth1 -p tcp -s 192.168.0.0/24 -d 192.168.0.10 --dport 1723 -j MASQUERADE
iptables -A INPUT -p 47 -j ACCEPT
iptables -A OUTPUT -p 47 -j ACCEPT
De firewall = RH7.3
VPN = RH9