I'm just wondering if anyone has an in depth understanding of the Linux networking stack and can tell me what the implications are for putting two interfaces on the same network in the same subnet.
Specifically, if you have a laptop connected via both Wifi and ethernet and both are active and have received IP addresses via DHCP, what would the expected result of that be?
Which interface would be used for traffic to our subnet?
Here is the way the routing table looks:
Destination Gateway Genmask Use Iface 192.168.5.0 0.0.0.0 255.255.255.0 eth0 192.168.5.0 0.0.0.0 255.255.255.0 wlan0 127.0.0.0 0.0.0.0 255.0.0.0 lo 0.0.0.0 192.168.5.254 0.0.0.0 eth0
The routing table indicates that eth0 is preferred for traffic outside my network but how was that determination made?
If I unplug the ethernet cable it immediately changes the routing table so that the wlan0 interface is the default gateway.
I'm wondering what controls that behaviour?