0

It is possible to have two different routes to the same destination network via two different interfaces?

I have a network I want to reach: 10.0.0.0/24 from a host with multiple (bridged) interfaces, one of which has an IP in the same network I want to reach ( 10.0.0.10). The other IP is 192.168.0.10.

By changing the routing, I'm able to ping either IP at a time, but I can't find a route/rule that will allow me to ping both IPs from the 10.0.0./24 network (the idea being to have a route/rule based on source network and destination IP).

2
  • 1
    I am not sure if I get you correctly, but if one of the IPs is already in the 10.X range, you don't need a route for that. Just add route for the 192.168.x adress Sep 6, 2021 at 18:25
  • Thanks, although I had already done that (first thing I did), your comment made look look further into the routing and found the answer. I just needed Reverse Path Filtering on that specific interface.
    – joovunir
    Sep 8, 2021 at 9:32

1 Answer 1

0

In my case enabling Reverse Path Filtering for "all" did the trick:

echo 2 > /proc/sys/net/ipv4/conf/all/rp_filter

In the case of a ping, the ICMP req will come from vlan 10 (10.0.0.10) and the reply will go via vlan 19 (192.168.0.10)

edited: I'm replacing the inteface "vlan1" with "all" because the former will only work as long as I manually remove the route to the other network (added by the OS). Using "all" will work even when the route is there.

1

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .