Using Multiple NICs

[mucols]

Hi Folks,

 

I'd like to learn how to set the default network card when I have two installed. I have one 100M card and one 1000M card; both are connected to their own nodes on my switch on my home Ethernet network (the switch has no control interface to my knowledge). Mandriva is automatically selecting my 100M card as my default card which seems to make my 100M card handle most of the incoming signals while my 1000M card handles most of the outgoing (which I think would be great if I wanted to ever make this computer a web server). Is there a way I can switch their functions when I know traffic will be acting in one direction or the other?

 

On another note, but on the same topic, is there a way to dedicate one card to one path? I was thinking the network would operate efficiently if one card was dedicated to the Internet and the other would be allowed to handle requests from my internal network; do you think my reasoning is correct or would this particular computer be better off with one card behaving as they are already (one in - one out)? I use this computer personally while two or three remote users on my network would access files and print from this computer - the remote users bypass this computer and connect to the Internet from the DHCP/Gateway/Router.

 

Thanks,

 

Jeff

Edited November 8, 2009 by mucols

[ianw1974]

Hi, it depends what you're trying to achieve. Without seeing the addressing scheme and the way the network is set up it would be hard. However, if I make some assumptions based on the 100MB for internet and the 1000MB for internal home use, then you would need to have two different network addressing schemes on both network cards for them to work correctly. Having them on the same IP range will cause you problems - like what you have now and I'm guessing both your LAN cards have the same network IP range.

 

So, for example, configure your internal network with:

 

192.168.1.0/24

 

network, and all machines will have an IP from this, replacing the 0 with whatever last octet you wish each of the machines to have. Then for internet access, assign a different IP range, let's assume:

 

192.168.2.0/24

 

and set your router with 192.168.2.1 and all the machines that require internet to have an IP from this IP range by binding it to the second card.

 

You will not configure a default gateway for the 192.168.1.0 network because it won't be required, since you are only using it for communicating with your internal machines. The default gateway for the machines would always be 192.168.2.1 with that IP bound to the 100MB card.

 

Then all internet traffic would go by 100MB and all internal traffic by 1000MB card.

 

Hope that helps and I explained it clearly.

[mucols]

Hi Ian,

 

I think that makes sense. So, if I wanted Internet on all of my other machines too they would have to be bound to the card on this machine configured 192.168.1.*?

[ianw1974]

It depends which one you allocate for internet use, in my example, 192.168.2.* would be allocated for internet use. But you can use whichever you prefer and where for internal/internet use.

 

What you can do with the machines that have one network card is bind both IP addresses to it for both 192.168.1.x and 192.168.2.x networks, and set the default route accordingly for internet access.