Using 2 ethernet devices in the same machine.

studiorat

Hello,

Here's the story. I've got two nearly identical computers running Ubuntu 10.04.
One of them has an extra ethernet device (PCI) connected to the internet using a static IP address configured in /etc/network/interfaces.

IP address xxx.xxx.xxx.42 (eth0 internet)

The internet works fine on this machine. As does the icecast server on it! In fact verything is working well when I switch the internet cable between devices and machines with both DHCP and Static addresses.

Now, I need to connect the second machine IP xxx.xxx.xxx.44 (eth0) back to the first machine, via a single CAT5 cable. So I can stream a live feed from the second machine to the first, which in turn streams out to the internet. Internet sharing (á la Mac) would be useful also.

To sum up I have the following :

Machine 1 (Icecast Server)
IP address xxx.xxx.xxx.42 (eth0) internet
IP address xxx.xxx.xxx.43 (eth1) computer to computer connection.

Machine 2 (DAW) workstation.
IP address xxx.xxx.xxx.44 (eth0) computer to computer.

I've got the gateways, DNS switched to 0.0.0.0 for the crossover connection.
Subnets are 255.255.255.0 across all three devices.

I'm looking for a way to hook this all up. Without any proper networking experience or terminology I'm finding it very hard to find any tutorials doing just what I want to do. So any pointers, links etc. would be very welcome.

Secondly I am wondering whether I should have two IP address for the two ethernet devices on the first machine. The IP's are static and I'm editing changes in the configuration files instead of the network manager. I'm guessing I do...

Finally when I try and ping from machine 1 to 2 to see is it working, is there a way I can make sure I'm pinging from the correct ethernet port (eth1).

Can I set up a network using mac addresses perhaps?

The idea at the end of the day it to have machine 1 broadcasting pre-recorded programs while machine 2 can be used to record and make programs to be broadcast. Then when the need requires, machine 2 will stream to machine 1 which in turn will switch over to re-broadcast live via Icecast.

studiorat

Perhaps this is more of a network type question. MiCr0 ??

lynchie

Assuming the nics in both servers have auto-mdix then you wont need a cross over cat5 cable to connect them.

After that, the easiest setup would be to place the pc-pc connection on a separate network, easiest being:

eth0: 192.168.1.1 /255.255.255.0
eth1: 192.168.2.1 /255.255.255.0

eth0: 192.168.2.2 /255.255.255.0

Should then be able to ping 192.168.2.2 from the server with 2 nics

Also, tcpdump -vv -i eth1 will show all traffic across the port

studiorat

That make sense I think.
So if I use
eth0: xxx.xxx.xxx.42 /255.255.255.0 (Static address from IT dept.)

and

eth1: 192.168.2.1 /255.255.255.0

eth0: 192.168.2.2 /255.255.255.0

or similar for the other NICs. The IT wallah's won't have a freakout because those IP address aren't on the network. Don't ask why they aren't doing this, it's a long story.

What about the gateways, DNS and search domains? Should I set them to 0.0.0.0, leave them blank (comment out the lines) or just use the default ones.

ressem

No. The Gateway of the DAW machine should be set to the eth1 IP on the Icecast machine.
The Gateway of the Icecast should be the one provided by the admin department.

Have you seen:
http://askubuntu.com/questions/169473/sharing-connection-to-other-pcs-via-wired-ethernet