Getting two network cards to work

[Princey]

I have two nics on my motherboard. One is connected to the home network, the other is for Internet. So far, I have to disable one when I want to connect to the other. Is there a way of getting the two to work together rather than manually disabling each other? I know under windows I can just remove the DNS server and the conventional way before Lucid doesn't seem to work. Network manager doesn't even allow you to set one as default for internet connection. Any ideas?

[GreyGeek]

Re: Getting two network cards to work

First, install wicd and remove knm:

sudo apt-get install wicd (which gets wicd BEFORE you tear down you wireless connection)
sudo apt-get remove network-manager-kde
configure wicd (but don't try to connect, it won't until the autoremove step below)
reboot
sudo apt-get autoremove

Then, use wicd to setup your Internet connection, and use the information found in chapter 25.7 and 28 of rute.pdf to configure your LAN. Google for rute.pdf and you'll find dozens of locations from which you can freely download it (or the html version).

[Princey]

Re: Getting two network cards to work

I don't have a wireless card, it's 2 gigabyte WIRED nics on my gigabyte motherboard, would that same still apply?

[oshunluvr]

Re: Getting two network cards to work

What exactly are your connection needs and exact current setup? It appears you have 1 nic attached to a modem and 1 to a router? Give us some more detail.

There are various ways to use dual NIC's - you can attach both to your network and "bond" them or use them in the way you are now. The advantage to your current setup is the other computers do not have internet access thus are more secure. The dis-advantage is if you're using your PC as the gateway then it must be up for the others to access the internet.

IMO you're better off doing this manually without and network manager at all - knetworkmanager is useless enough to be alpha version (again - just my opinion). Remove all your knetworkmanager stuff as suggested and skip the wicd install.

You'll need to connect to the internet manually so before you remove network manager - copy the contents of /etc/resolv.conf because the unfriendly knetworkmanager will delete it when it's un-installed. Keep your liveCD handy in case you can't get back on line and need an alternate way to do so.

Your network cards are setup in /etc/network/interfaces which right now is likely rather sparse. It should look like:

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto eth0
iface eth0 inet dhcp

# The secondary network interface
auto eth1
iface eth1 inet dhcp

This should bring up both NIC's with unique IP's.

/etc/resolv.conf contains DNS nameserver information.


Once you've cleared knetworkmanager off - restart your network and look at your default settings.
Here are some commands you'll need in a terminal (commands in bold. comments in ital):

sudo service networking restart restarts network without a reboot, also stop and start can be used

ifup eth0 brings eth0 up using the default setting from the interfaces file


If you restart your network and are not on-line. Report the contents of /etc/resolv.conf and /etc/network/interfaces and the results of these terminal commands: ifconfig and route

[Princey]

Re: Getting two network cards to work

Thanks for the information, let explain what my current setup is, and what is what I want.

I have one nic, eth1 connected to my DSL modem which I access the internet with.

Nic two, eth0 is connected to a modem which serves the rest of the pcs on the home network that I do not want connected to the internet, so, no, I'm not looking to setup ICS or a gateway.

I want both cards to work at the same time as my home media center runs on that network. Right now, I can only access either the home network or the internet by bring up one and turn off the other via the command prompt. Hope I'm being clear here.

I am used to just removing the DNS server under Windows for the router running the home network, but seeing I no longer run that OS, I want to find a flawless way to do it without manually bring up and turning off either of the cards to enjoy simultaneous use of the two nics and networks.

[GreyGeek]

Re: Getting two network cards to work

....
I have one nic, eth1 connected to my DSL modem which I access the internet with.

Nic two, eth0 is connected to a modem which serves the rest of the pcs on the home network that I do not want connected to the internet, so, no, I'm not looking to setup ICS or a gateway.

I want both cards to work at the same time as my home media center runs on that network.
....

Is that really a modem that eth0 is connected to, or an router (active or passive)?

If it is a modem then which ever nic card is activated last will determine what is in /etc/resolv.conf and the router table as well. I suspect you will have to configure your network manually. To that end here is some interesting information:
http://www.aboutdebian.com/network.htm

Here is another good site: http://www.linuxhomenetworking.com/w...he_DHCP_Server

In fact, there are LOTS of howto's and resources for setting up Debian based networks:
http://lmgtfy.com/?q=debian+home+network+howto

[Princey]

Re: Getting two network cards to work

eth0 is connected to a linksys wired router, eth1 is connected to a DLINK wireless router that's in turn connected to my DSL router. I'll check that link out. Thanks.

[wizard10000]

Re: Getting two network cards to work

eth0 is connected to a linksys wired router, eth1 is connected to a DLINK wireless router that's in turn connected to my DSL router. I'll check that link out. Thanks.

Why not just plug them all into the same router and disable internet access on the router for the machines you don't want on teh intrawebz?

[Princey]

Re: Getting two network cards to work

I can't. Both because of distance and other purposes which I rather not go in to here. Before I made the complete migration to Linux, I ran everything fine under Windows. When I transferred across, I was able to do just fine using Wireless. But since I purchased this new rig, I bought the mobo with 2 nics to make it simpler, I'd think as I don't want to use my laptop all the while.

[oshunluvr]

Re: Getting two network cards to work

Using your /etc/network/interfaces file:

# The primary network interface
auto eth0
iface eth0 inet dhcp
gateway 192.168.1.1
netmask 255.255.255.0

# The secondary network interface
auto eth1
iface eth1 inet dhcp
gateway 76.24.107.100
netmask 255.255.255.0


or something like that...

You can test this or try bring them both up at the command line. You might want to use static IP on your network.

You'll probably have to set routes for each interface too but that's not too hard either.

In your interfaces file:

up route add -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.2.1
down route del -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.2.1

just examples...

[Princey]

Re: Getting two network cards to work

Thanks guys, I think I got it to work. What I did was to set the one on the home network to static, remove the DNS and that solved the issues.