Two eth interfaces, but one only with internet...

Creak · 03-11-2005, 04:04 AM

Hi

I have 2 eth interfaces (onboard and pci card) and when I plug the cable on the first one (eth0), the internet doesn't work (no dns), but when i plug the cable on the eth1, it works... BTW the 2 cards can see the internal network. Here is my /etc/networks/interfaces:

Code:

# The primary network interface
auto eth0
auto eth1

## DHCP
#iface eth0 inet dhcp
#iface eth1 inet dhcp

## Static
iface eth0 inet static
    name Carte Ethernet (onboard)
    address 172.16.130.220
    network 172.16.130.0
    netmask 255.255.255.0
    broadcast 172.16.130.255
    gateway 172.16.130.254

iface eth1 inet static
    name Carte Ethernet (pci)
    address 172.16.130.221
    network 172.16.130.0
    netmask 255.255.255.0
    broadcast 172.16.130.255
    gateway 172.16.130.254

And my /etc/resolv.conf:

Code:

nameserver 10.42.6.6
nameserver 10.42.6.7

peter_robb · 03-11-2005, 07:35 AM

Take a look at ip route list and see which interface is listed as default

This will be the interface internet traffic (non-local traffic) will use..

What are you trying to achieve with two interfaces on the same subnet?

Creak · 03-11-2005, 08:15 AM

I don't understand the stuff about the "ip route list"... I take a look where? Google?

The problem comes from the configuration of the PCs in my schools... There are 2 eth cards and the cable isn't always on the same plug. I'm just bored of switching between the 2 interfaces and i want to know a way of making it automagically

peter_robb · 03-11-2005, 11:07 AM

I wish it was easier than that..

Do ip route list in a command line or route -n

Someone had a sense of humour when they set it up, coz it's a basic routing mistake to have 2 possible connections like that without some special programming to swap between them..

Creak · 03-11-2005, 03:31 PM

I know "ip route list" doesn't work (ip is not a known executable). But route does work, but i'm at home right here, i'll try tomorrow!

gsgleason · 03-11-2005, 04:04 PM

it's generally not a good idea to have two interfaces on the same subnet, and on top of that, each with a default gateway.

I would remove the configuration for one of them and just use the other.

Creak · 03-12-2005, 01:52 AM

That's what i used to do, i was just searching a way to prevent me to switch the cable between the 2 cards, because the cable isn't plug on the same card each time...