We are trying to enable L2TP passthrough to a Mac OS X Mavericks server. L2TP passthrough is fairly trivial on other routers, but our Fortigate 40C with FortiOS 5 is making it quite the challenge.
I' ve setup port forwarding via Virtual IPs with the following:
UDP 500
UDP 4500
UDP 1701
Then created a Policy entry as
Incoming: wan1
Address: all
Outgoing: internal
Destination: the above VIPs
Schedule: always
Service: ESP, IKE, L2TP
I' ve tried turning off/on NAT in that Policy, setting AutoIPSec to ' on' on the wan1 interface, having the router' s VPN on and off, adding other Ports (TCP 500, 4500, 1701, and 1293 both TCP and UDP). Still no luck.
I' ve confirmed the VPN service is functioning properly on the OS X Server by connecting from an internal client just fine.
I enabled logging on the Policy, and if VPN on the router is turned on I see the connections come from the external device on ports 500 and 4500 only. If VPN on the router is off, I get 0 packets on that Policy.
Any help would be most appreciated! I' m familiar with routers, command line tools, etc., but not an expert on Fortigate.