debian: two ethernet devices, only one works at a time

petermbm · 09-27-2005, 12:09 PM

I got a Sony Vaio Laptop with an e100 wired lan and ipw2200 wireless lan. Both interfaces work fine, but only when activated on their own.

When I first bring up the wlan, and after that bring up the normal cable lan interface, only the wlan can ping machines on the local net and internet. If i do it the other way round, i can ping via the cable lan, but not using the wlan interface.
Can I make both interfaces work as normal at once? I guess it has something to do with my route settings maybe...

Although the system is debian, I made a custom network start script which goes like this:
(eth0=wireless, eth1=cable lan)

Code:

iwconfig stuff , essid, wep and so on... this should be alright.

ifconfig eth0 192.168.1.96 netmask 255.255.255.0
ifconfig eth0 up
ifconfig eth1 192.168.1.92 netmask 255.255.255.0
ifconfig eth1 up
route add default gw 192.168.1.1

However, only the first device brought up "works"....

otchie1 · 09-29-2005, 09:07 AM

just interested,,,how do you know only the first device works? How are you trying to route your packets and, frankly, why if they both go to the same gateway?

petermbm · 09-29-2005, 09:20 AM

I do it with ping -I ethX 192.168.1.1, and with the second activated, "non-working" device,
it always says destination host unreachable, no matter what ip i ping.
When I bring up eth0 first, eth1 won't ping anything, if I bring up eth1 first, eth0 wont ping.

All I do with route is set the default gateway 192.168.1.1.
I dont have much experience with route, what is the correct way to get both interfaces to use 192.168.1.1 as a gateway?

otchie1 · 09-29-2005, 12:10 PM

you need load balancing software for that as a given app would have to divide its packets between two NICs. That's probably why one of the NICs is always suspended.