> > Please explain to me how the ethernet interface could interfere with the > wireless interface. I must be missing something critical here because > they're on different interfaces (eth0 and wlan0), and while both are UP, > only one is RUNNING. > > Thanks, > > Rich >
There can be more than 1 default route in the routing table. This often the done in a mult-nic configuration as each ip network will have a gateway of last resort. The problem here is that your route table has cached the default route for eth0, eth0 is not connected to any network and that interface is being preferred either based on metric or just because that interface is listed in the routing table first based on alphanumeric sequence. Which when I statically configure eth0 on the same ip net as wlan0, my routing table now shows eth0 default route listed first... 0.0.0.0 10.0.0.1 0.0.0.0 UG 0 0 0 eth0 0.0.0.0 10.0.0.1 0.0.0.0 UG 0 0 0 wlan0 The routing table makes the decision on which interface to send packets out based on metrics. If the default route for eth0 is lower than wlan0 than that's the interface the routing table sends the packets to. I'm not sure if metrics are assigned automatically in sequential order by interface name such that eth0 would always have a lower metric than wlan0. I did some of my own testing and here's what I've discovered. 1. I added a static ip addr stanza for eth0 to /etc/network/interfaces and then brought up eth0 without it being physically connected. ~# ifconfig eth0 Link encap:Ethernet HWaddr 00:15:58:82:11:2e inet addr:192.168.1.10 Bcast:192.168.1.255 Mask:255.255.255.0 Here's the routing table w. 2 default routes on different nets with both Default Routes have a metric of 0: :~# route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 10.0.0.0 0.0.0.0 255.255.255.0 U 0 0 0 wlan0 192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 0.0.0.0 10.0.0.1 0.0.0.0 UG 0 0 0 wlan0 0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 eth0 Traceroute shows packets are being routed out wlan0 interface: :~# traceroute www.google.com traceroute to www.google.com (74.125.127.104), 30 hops max, 60 byte packets 1 10.0.0.1 (10.0.0.1) 2.000 ms 1.997 ms 2.060 ms 2 * * * 3 te-0-0-0-6-ur03.troutdale.or.bverton.comcast.net (68.85.150.177) 10.373 ms 16.574 ms 17.475 ms So, it seems you have a stale route table cache entry for eth0 that is buggering up your routing. I suspect if you run a traceroute you'll see packets attempting to go via eth0? What happens if you run this command to flush the routing table cache and then connect to the wlan? "ip route flush scope global type unicast" Oddly enough, even with 2 default routes on the same ip net, packets are still be routed through wlan0. I didn't expect this to be the case. Maybe the superior intelligence of Debian? ;-P :~# route Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 10.0.0.0 * 255.255.255.0 U 0 0 0 wlan0 10.0.0.0 * 255.255.255.0 U 0 0 0 eth0 default 10.0.0.1 0.0.0.0 UG 0 0 0 eth0 default 10.0.0.1 0.0.0.0 UG 0 0 0 wlan0 :~# traceroute google.com traceroute to google.com (173.194.33.38), 30 hops max, 60 byte packets 1 10.0.0.1 (10.0.0.1) 0.930 ms 1.703 ms 2.005 ms 2 * * * 3 te-0-0-0-6-ur03.troutdale.or.bverton.comcast.net (68.85.150.177) 17.533 ms 17.687 ms 17.684 ms 4 be-1-ur04.troutdale.or.bverton.comcast.net (68.85.243.170) 17.422 ms ae-4-0-ar03.beaverton.or.bverton.comcast.net (68. Cheers, Mike _______________________________________________ PLUG mailing list PLUG@lists.pdxlinux.org http://lists.pdxlinux.org/mailman/listinfo/plug