My CSF firewall seemed to be blocking internet access using my VPN. I could connect to it but could not use the internet connection. Here is a solution to the problem:
Create File
vim /etc/csf/csfpre.sh
Insert This
iptables -A INPUT -i eth0 -p tcp --dport 1723 -j ACCEPT iptables -A INPUT -i eth0 -p gre -j ACCEPT iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE iptables -A FORWARD -i ppp+ -o eth0 -j ACCEPT iptables -A FORWARD -i eth0 -o ppp+ -j ACCEPT
Save File and Give Executable Permissions
chmod +x /etc/csf/csfpre.sh
Create File
vi /etc/csf/csfpost.sh
Input Text down
service pptpd stop service pptpd start
Save File and Give Executable Permissions
chmod +x /etc/csf/csfpost.sh
Restart CSF
csf -r
I have tried this script and similar scripts with softether vpn and it does not work – the client does not connect if the csf is running.
Though if I start csf when the vpn connection is established, the connection does not break.
Do you have any ideas?