My thinkpad has two network interfaces, one wired and one wireless. Both interfaces can be connected to a router which in turn is connected to the Internet.
If both interfaces are connected, are both interfaces used simultaneously or just one at a time. How can I tell which interface is used?
Best Answer
I activated my wired eth0 and wifi eth2 with network manager (both dhcp):
tcpdump -n -i eth0
shows traffic, whiletcpdump -n -i eth2
doesn't.So let's try to reorder the interfaces in the routing table:
Now the routing table is:
now tcpdump shows all the traffic going through the eth2 interface.