NIC ordering

[b56r1]

What is NIC ordering on bootup of Linux machines? what is its significance ? can anyone tell in detail.

[Lazydog]

By MAC address. By editing your eth# config files you can set the NIC to the interface you want it to be.

[atreyu]

Note that some newer Linux distros (Fedora 16, I can verify) are using a newer kernel-based network device naming convention that is meant to be more consistent and reliable. It is based upon the physical location and interface type of the hardware.

For example, what once was my eth0, is now p32p1 (the first p is for PCI and the 2nd is for Port, the first p could alternatively be em to indicated a NIC that is Embedded on the motherboard).

You can read more about it here:

Consistent Network Device Naming coming to Fedora 15 | domsch.com blog

[Lazydog]

I didn't know this. Thnx for the link. I for one would never use this.

[atreyu]

I for one would never use this.

yeah, exactly how I felt when I first heard about it. Thankfully, you should just be able to do this to disable the new and improved naming scheme (haven't tried it myself):

biosdevname=0

More on that at Fedora's official page on device naming:

Features/ConsistentNetworkDeviceNaming - FedoraProject

[bleedingsamurai]

For example, what once was my eth0, is now p32p1 (the first p is for PCI and the 2nd is for Port, the first p could alternatively be em to indicated a NIC that is Embedded on the motherboard).

That sounds very similar to how BSD kernels name devices. I think it is pretty cool but I started with GNU/Linux so I prefer the eth0, eth1, eth2 method.
udev still does a pretty good job of letting the user specify what devices should be in what order.