On Fri, Aug 2, 2013 at 10:25 PM, lleachii@aol.com wrote:
172.31.255.254 is merely my tunl0 IP address, it's a Private IP in the Class B range, using a /32 (a single host on the network), nothing works using that IP address but ping from my 44LAN.
44.60.44.1 is the IP of my eth1 interface, everything is handled on my device via IP forwarding.
Lynwood,
When someone does a traceroute to your network behind the gateway, and you receive traceroute's packets on the tunl0 interface, I think your kernel will respond to those packets using the tunl0 IP address. If you have a private 172.31 address there, instead of a 44 address, the 172.31 address will show up on the traceroute instead of your registered net-44 address (unless the non-amprnet source address will be filtered at the other end of the tunnel). Also, when any applications on that router box (if you have any) will initiate connections to the amprnet, they'll use the outgoing interface's IP address as the source address by default, unless some other magic configuration is applied.
It might be a good idea to just reuse the 44.60.44.1 address on tunl0, with a /32 mask. Might reduce confusion at some point later on. You're right in that it doesn't really make any difference when simply forwarding packets.
- Hessu