Faking eth0

Some software likes the MAC address of your first ethernet device to be set to a specific value. On Linux, this is trivial:

Edit /etc/udev/rules.d/70-persistent-net.rules to name your ethernet card eth1. To make these changes take effect, use modprobe to remove and re-insert the kernel module for your card's driver. If you don't know what this means, reboot your system.

# modprobe dummy
# ip link set name eth3 dev dummy0
# ifconfig eth0 hw ether DEADBEEFCAFE

To make this permanent, add the following lines to the listed files:

/etc/network/interfaces

iface eth0 inet static
    hwaddress DE:AD:BE:EF:CA:FE

/etc/udev/rules.d/70-persistent-net.rules

SUBSYSTEM=="net", KERNEL=="dummy0", NAME="eth0"