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How do I accept CIPE connection requests coming from the outside?
CIPE stands for Crypto IP Encapsulation (see howto Establishing a CIPE Connection) . It is used to configure an IP tunneling device. For example, CIPE can be used to grant access from the outside world into a Virtual Private Network (VPN). All you need to find out CIPE number, once you got the number (device name) append following two IPTABLE rules (add rule to your iptables script) to script:
Iptables rules:
Add the following rules to your iptables script or configuration file:
iptables -A INPUT -p udp -i cipcb0 -j ACCEPT iptables -A OUTPUT -p udp -o cipcb0 -j ACCEPT
CIPE use its own virtual device. It is use to transmit UDP packets so the above rule allows the cipcb0 interface to incoming request (no need to use eth0).
Replace cipcb0 with your actual device name.
References: