Wireless NIC in FreeBSD 6.0 ?

[Erik Nørgaard]

Yuan Jue wrote:
> On Sunday 25 December 2005 19:53, you wrote:
> yes. they are not on the same LAN.
> but when I use my local NIC to connect the internet, everything is fine.
> the following is how my local NIC works:
> 
> YuanJue@~$ ifconfig
> bge0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
>         options=1a<TXCSUM,VLAN_MTU,VLAN_HWTAGGING>
>         inet 166.111.208.204 netmask 0xfffffe00 broadcast 166.111.209.255
>         ether 00:0d:9d:90:e0:68
>         media: Ethernet autoselect (100baseTX <full-duplex>)
>         status: active
> lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384
>         inet 127.0.0.1 netmask 0xff000000
> YuanJue@~$ ping 166.111.8.28
> PING 166.111.8.28 (166.111.8.28): 56 data bytes
> 64 bytes from 166.111.8.28: icmp_seq=0 ttl=251 time=0.525 ms
> 
> why does this work? it has the same netmask and broadcast address
> as the wireless NIC. Any more explanations? 

OK, now, if you have two nic's configured for the same lan things get 
wierd. Try

# ifconfig bge0 down

And, check that default route is set correctly.

I think the default route binds not only to an ip but also to the 
interface that connects to that network, so maybe you have configured 
both bge0 and ath0 and default route set to go out bge0. Now, when you 
disconnect bge0 and try to ping, your ping is not sent on ath0 as you 
might think but on bge0.

To check this kind of problems, use snort to sniff what's actually 
leaving your interface.

Cheers, Erik
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