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Using Cisco VPN Pass Through Behind pfSense¶
If trouble is encountered when attempting a connection from an internal Cisco VPN client to an external host, (e.g. a workstation with the Cisco client is trying to get out through a pfSense® firewall to connect to a “foreign” site), then try the following.
In the Cisco VPN client software, Modify the connection and turn off transparent tunneling completely in the Transport tab.
In the pfSense webGUI, under Firewall > NAT on the Outbound tab:
Enable Manual Outbound NAT.
Remove any NAT rules that perform static port NAT on udp/500.