[mythtv-users] OT: default routes

[Simon Hobson]

Hika van den Hoven <hikavdh at gmail.com> wrote:

> The VPN server is running on the router and there are two VPNs: One a
> remote network with a changing internet IP and the other my roaming
> laptop or tablet.

Are these both "dial in" then ?

That may simplify things a bit. AIUI, this is what should happen :
1) Other endpoint "dials in" to the fixed IP
2) The VPN "system" should respond using that fixed IP in the source address of the outgoing packets.

At present, 3) it fails as the default route is via the other ISP so the outbound packets most likely (if it's a good netizen) get dropped by your ISP as "impossible". So what you need is a route (based on source address) to pass that traffic via the correct interface.

You can probably get by with nothing more than the basic routing rules that say "source IP is a.c.b.d, route via this table", and create the extra routing table to route that traffic via the ISP with fixed IP address. Leave the default gateway pointing at the new ISP and that'll handle all traffic other than that which originated at the fixed address.

So I *think* that if you simply copied the routes and rules from my original post (substituting the various IPs etc) it'll just work.
And of course, setup the VPN/PPP system so it adds/removes the routes for the far end to an appropriate routing table - I think main would be the default, and also suitable as it's checked early on in the rules.