Hi there!
I'm trying using two ISPs together (Xnet and Woosh) to give some redundancy to my net connection, both for outgoing and incoming traffic.
Outgoing is sorted - the usual default route goes to my ADSL router with internal IP 192.168.0.1. The ADSL router itself has been set up with a default route pointing to 192.168.0.2 (ie back into the LAN) which is another router which talks PPPoE to the Woosh modem plugged into it.
So if the ADSL line is down, then the ADSL router sends outgoing traffic via the Woosh link. Eventually I'll set it up gc_timeout on my Linux boxen to improve on this a bit.
However it isn't working how I'd like it to with incoming traffic.
I use SSH to get into my machine remotely, and there's a webserver which can be seen by a couple of clients of mine. I want to be able to get in using the public IP of either connection. Trouble is, when the incoming connection comes via Woosh the server tries to route the reply out via the ADSL as it's the default route.
I can find online some stuff regarding using iptables and iproute2 to tag and route traffic but it seems to depend on having multiple interfaces on the server (eth0, eth1) whereas with my setup there's just eth0 and then two routers on that LAN.
Anyone got any tricks for routing traffic out on the same connection it came in on? Google hasn't been as much my friend as I'd hoped!
Thanks
Andrew