[NTLUG:Discuss] Which nic the gateway?

[Michael Barnes]

I have a quick manual fix as well, "#ifdown eth0", "#ifup eth1" and it 
all works fine after that.  However, it all worked fine until I needed 
to do some network testing and temporarily assigned a static IP to the 
on-board NIC.  Once I restored that to the normal DHCP service is when I 
started having the problems.

It would seem to me there should be some configuration I can set 
someplace which would not allow a route through a nic which had no 
connection or could not pull DHCP.  Every other machine I have had 
experience with would default to a 167.? address (or something like 
that) and not be in the routing table if it did not pull DHCP. The 
on-board nic defaults to the last DHCP information it had in a cache 
somewhere.

Michael


Stephen Davidson told me on 9/14/2006 6:42:
> HI Michael.
> 
> I have a script that I manually run (SuSE 10.0 on a Dell Latititude, but 
> should give you some idea).  The script does the following;
> 1) 'Eject' the built in Wireless (there are some wireless networks in 
> the vicinity that confuse things, and I have NOT figured out how to 
> support multiple wireless secure and unsecured networks in Linux)
> 2) Restart the networks services (forces a cleanup of the network stack)
> 3) /etc/init.d/network down eth0 (shuts down the onboard NIC)
> 
> After that, everything normally runs happily through the Docking 
> Station's NIC.
> 
> Regards,
> Steve
> 
> Michael Barnes wrote:
>> I've got a Dell laptop running SUSE 9.2.  It has a built-in NIC (eth0) 
>> and a second NIC (eth1) in the docking station.  When I come into the 
>> office and put it into the dock and fire it up, it pulls DHCP from the 
>> server.  My problem is, when using the dock, DHCP assigns a static IP 
>> address, but assigns the gateway as reachable via eth0.  Then I have to 
>> go to command line and ifdown eth0, then ifup eth1 to re-pull DHCP and 
>> set the gateway reached via eth1.  Once I do that, then all is happy 
>> until I reboot.
>>
>> I cannot seem to find anything in the DHCP configuration which allows me 
>> to specify a specific NIC to use, or anything in the laptop that lets me 
>> turn off the laptop NIC when in the dock.
>>
>> Thanks for any ideas,
>> Michael
>>