Routing with multiple Interfaces


I have 2 WAN interfaces one is DS-Lite and one ist a native IPv4 connection. I want to route everything outgoing via DS-Lite but want still to allow incomming connections to my clients via port forwarding via the native IPv4 connection.

My problem is that if i route all outgoing via the DS-Lite interface portforwarding does stop working, what routing setting i must set so port forwards keep working?

I'm a littlebit lost with that.
Thanks everybody for help

You cannot send server traffic outbound to another ISP - it must be the same as the port forwards are configured to. Otherwise, you must alter the port forwards to the other ISP.

Thank you for your response, but i don't understand why. Shouldn't OpenWRT be able to track the state RELATED and ESTABLISHED so it knows over which interface a connection has to go?
Can you point me to some more information?
Thank you

You configured outbound traffic on a different connection than your inbound service ports. Simply set the server to use the same ISP as the port forwards. The remaining hosts can use the alternate ISP. This can be done with ip rules.

On what?

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Sadly that is not possible for me

Why this doesn't work. I mean it is like NAT. You open a connections up to a IP and the router knows which internal client did the requests and routes the answer to the internal IP, why can't i do the same thing here just for incomming requests?

Or maybe I'm completely wrong here and i did over see something?

@ vgaetera Thanks i take a look at that

Have you looked at Mwan3? I'm not sure but maybe it can be used. (The inbound wan needs to be tracked using firewall marks in the connection tracker anyway.)

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It’s not like NAT, it’s routing. Different processes with different rules.

It is potentially that ISP2 blocks the packets ingress as their source IP is “wrong” in that return packets would not go back over that path. This would be good practice for the ISP to protect against IP spoofing and various kinds of attack’s.

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of course they do, that is the whole point behind my attempt to route answer to requests over the interface where they origin from

nope mwan3 doesn't work, it does not accept my IPIP6 Tunnel as valid interface.

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