pinging out of a specific interface...

Out of a specific interface.

Ie, say i have 2 NICs in my machines. One goes to my switch for internet access, one goes to to my lab... is it possible to ping, but have it go out of a certain interfacE? It seems the only way to really do the labs is to disable internet access to my computers and use the other NIC for the labs... call me lazy.. but i hate to have to re-cable my network every time i setup for a lab.

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tech-airman

Darthn3ss wrote:

Out of a specific interface.

Ie, say i have 2 NICs in my machines. One goes to my switch for internet access, one goes to to my lab... is it possible to ping, but have it go out of a certain interfacE? It seems the only way to really do the labs is to disable internet access to my computers and use the other NIC for the labs... call me lazy.. but i hate to have to re-cable my network every time i setup for a lab.

Darthn3ss,

Which operating system are you using?

Darthn3ss

one is ubuntu server 6.06, one is xp pro, one is xp mce.

Darthn3ss

any ideas?

blackmage439

Why do you have to disable your other NIC for your labs to work? I'm led to believe that if you have two NICs in your system, the ARP table on your local machine should automatically direct traffic out the correct interface. And if your machine doesn't know where, for example, a ping should go, it would just issue an ARP request out both NICs.

It's been too long since I had to think about this stuff... someone correct me if I'm wrong. :P

Ahriakin

Routing will control the interface chosen I believe. If there is no static entry it will use the Default Gateway for the Interface with the lowest metric Each interface will have a default gateway shown as destination 0.0.0.0 0.0.0.0 if you do a Route Print but one will have a lower metric than the other (which you can manually set in Advanced TCP properties). You could add static routes or manipulate the Metric as needed.
In your case if you do a Route Print you'll see the default gateway for the internet connected NIC is the lowest metric, which is how it should be. The best thing to do is use Route Add xxxxxx to place static routes for your lab subnets that use the other NIC as the gateway - don't forget to make them persistent, it's all in the command line help when you run Route /?

Darthn3ss

ahh thanks i'll play with that in a few minutes when i start my labs. this also may be a semi dumb question and i havn't googled it yet but how do i change the ip and such on my linux box, theres no gui and i'm dumb without that :-p i'm sure its a ifconfig thing?