{{MessageBox|backgroundcolor = #faa|image =Warning.png|heading =WARNING|message = This is recommended only for advanced users, proceed with caution.}} = Step 1 = You can manually force the assignment from a network card to what device comes up as (eth0, eth1 ...), you by changing the udev rules. You can manually edit this file:

This file maps MAC address to device name.  '''Example'''<small> SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:1d:60:b5:43:66", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0" SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="5c:d9:98:af:21:43", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="et1"</small> This file maps the card with MAC 00:1d:60:b5:43:66 to eth0 and the card with 5c:d9:98:af:21:43 to eth1. If you want to reverse the assignments, switch eth0 and eth1 at the end of the entries. Or delete one of the entries. = Step 2 = You may need to also edit this configuration file as well:  /etc/sysconfig/network-scripts/ifcfg-eth0 if it has the MAC address for the device in it (e.g. in a variable called HWADDR). '''Example'''  HWADDR=00:1d:60:b5:43:66

{{Code| # PCI device 0x10de:0x03ef (forcedeth) (custom name provided by external tool)SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{You will need to adjust the HWADDR to match the MAC address}=="00:1d:60:b5:43of the card you wish to make eth0. Note:66", ATTR{type}=="1"if you wish to keep eth1 active, KERNEL=="eth*", NAME="eth0"you may also have to edit ifcfg-ith1 as well.

'''Please exercise care. Improperly modifying this file these files may render your system without network or even not boot properly.'''