Multiple LAN Cards
 

I've got a pair of Identical 10/100 cards, Linksys that I want to assign the same mac address to. That way I'll have more available bandwidth to my computer on the LAN. I know that this won't really help me with internet, I'm still limited to my normal D/L speed on the router.

Shouldn't this work? Having two cards with the same MAC address?

Also, how does one statically set the MAc address on a linux machine, I run the 2.6.9-677 Kernel of the Fedora Core 3 release.

Hi,

you can set the HW address of a NIC by using ifconfig:
ifconfig eth0 hw $HW_ADDRESS eth0

but that won't do what you want: you need some software to do loadbalancing (if you set up 2 NICs with the same MAC, then the first one to reply ARP request will be the only one used, and moreover the switch on which you're connected might make some errors).

what you need is link aggregation : http://linux-ip.net/html/ether-bonding.html

but you must have a switch that's able to support etherchannels...

One way of doing this is to 'bond' the cards together using the bonding driver within the kernel, when its setup both cards behave as one, with a single ip, you then have several config options, such as active backup mode for fault tolerance, or load balancing for more bandwidth.

Its documented in the kernel source tree under Documentation/networking/bonding.txt

HTH

Mad.

Changing the MAC address won't get you double the bandwidth, it will probably just cause some network issues on your LAN. If the switch (and I say switch because if you are using a hub then nothing you do will make it faster because the whole LAN shares the same bandwidth anyway) supports it, you can set up a port trunk but most home networking devices don't. Otherwise trying to 'fool' the network into doubling bandwidth with two NICs by giving them the same [IP/MAC address] won't do anything but cause problems as the other network devices try to determine why two nodes on the network are using the same settings.

As far as overriding the MAC, it can be done with ifconfigand for that to work, the NIC driver has to support overriding the default hardware address, I have no idea if the linksys module does or not.

You CANNOT alter the MAC address of a NIC (Network Interface Card). The hexadecimal number for each NIC card is unique and is so for a very good reason.
Every TCP/IP packet sent and recieved in a LAN contains the MAC address of the NIC so that the router can forward the the TCP/IP Frame (basically a Packet for LAN) to the correct computer. If in theory you managed to alter the MAC address your router would send the frame to both computers. Reducing the bandwith for every PC with the same MAC address, even though the frame is only destined for one particular computer!
Hopefully this has answered all your questions. If I can give some more advice, try reading a book about networking. It will introduce to some concepts that are fundamental to networking.:D

Re,

I don't like saying things like this, but kirandip_sidhu, you should read this networking book too....

Sorry, just read the above posts. Who would have thought you could mask the MAC address? Spent too long on windows:tisk: And by reading the website below. it turn out you can mask the MAC address of windows as well.

http://www.irongeek.com/i.php?page=security/changemac

To be perfectly honest I would'nt change the address, it will only cause problems in the long run:cry: