FreeS/WAN IPSec configuration manual, introduces the connection methods based on pre-shared keys, Gateway-Gateway, Net-Gate, Net-Net, mixed mode and X.509 certificate-based connections
The document explains how to configure FreeS/WAN on Linux and Windows platforms. It includes sample ipsec.conf files, keying options, and instructions for defining left and right security gateways, subnets, and shared secrets.
It also describes debugging options such as klipsdebug and plutodebug, manual start settings, and other advanced parameters like uniqueids and overridemtu. The final sections list the available ipsec_klipsdebug(8) and related command‑line options.