IPsec and firewall rules

When an IPsec tunnel is configured, pfSense® automatically adds hidden firewall rules to allow UDP ports 500 and 4500, and the ESP protocol from the Remote gateway IP address destined to the Interface IP address specified in the tunnel configuration. When mobile client support is enabled the same firewall rules are added except with the source set to any. To override the automatic addition of these rules, check Disable all auto-added VPN rules under System > Advanced on the Firewall/NAT tab. When that box is checked, firewall rules must be manually added for UDP 500, UDP 4500, and ESP to the appropriate WAN interface.

Traffic initiated from the remote end of an IPsec connection is filtered with the rules configured under Firewall > Rules on the IPsec tab. Here restrictions may be placed on resources made accessible to remote IPsec users. To control what traffic can be passed from local networks to the remote IPsec VPN connected devices or networks, the rules on the local interface where the host resides control the traffic (e.g. connectivity from hosts on LAN are controlled with LAN rules).