Does anybody know if it is possible to configure GRE IPSec tunnel between Cisco 2811 router and FortiGate 110C firewall? I know that FortiGate supports IPSec and GRE tunnels, but maybe somebody succeeded in establishing an IPSec GRE between those routers? Could you also give a link to the appropriate documentation if it is possible?
Is there any specific reason for planning to have GRE over there ? I would suggest checking the below links and the links embedded inside the link.
the reason why I need GRE over IPSec is to pass RIP routing updates via VPN tunnel. I don't know if it is possible in Cisco IOS to configure IPSec VPN using crypto maps and pass routing updates via that tunnel.
You can configure the GRE tunnel on the 2811.
I'm aware that you can configure sort of a GRE tunnel on the Fortinet as well, but I have not seen a GRE tunnel between a Cisco and other vendor.
I've only seen GRE tunnels between Cisco devices (however I have not tried it to assure you that it will not work :-()
Refer to this configuration guide.
Please rate replies and mark question as "answered" if applicable.