Actually, I know what the MAC is for the builtin Port1 and 2. Those are listed in the BIOS. But ultimately I don't want to rely on them as I want the same kickstart file to work for other machines, so hardcoding those in the kickstart file wouldn't quite work, unless I start writing multiple kickstart files, one per machine. Anyway, lspci reports this: 00:19.0 Ethernet controller: Intel Corporation 82566DM-2 Gigabit Network Connection (rev 02) 03:00.0 Ethernet controller: Intel Corporation 82572EI Gigabit Ethernet Controller (Copper) (rev 06) 08:00.0 Ethernet controller: Intel Corporation 82573V Gigabit Ethernet Controller (Copper) (rev 03) Now when I look at the enumeration from dmesg, I get this: e1000e 0000:00:19.0: eth0: (PCI Express:2.5GT/s:Width x1) 00:1e:68:58:00:4c <-- this is Port1 e1000e 0000:03:00.0: eth1: (PCI Express:2.5GT/s:Width x1) 00:15:17:d3:43:62 <-- PCIe Card e1000e 0000:08:00.0: eth2: (PCI Express:2.5GT/s:Width x1) 00:1e:68:58:00:4d <-- this is Port2 So this is how it gets enumerated for some reason. But during the machine's POST, it always brings up the PXE boot order as Port1, Port2, and finally the PCIe card, which is the correct order that I want it in. It also only has one single expansion slot so it's not like I can try a different one to see if it makes a difference, unfortunately. On Thu, May 14, 2015 at 5:47 PM, Kahlil Hodgson < kahlil.hodgson at dealmax.com.au> wrote: > On 15 May 2015 at 03:51, Ashley M. Kirchner <ashley at pcraft.com> wrote: > > > After the machine boots and I look in /root/ksnet-devices, I see the MAC > > addresses for the devices as: > > Port1 -> eth0 > > PCIe Card-> eth1 > > Port2 -> eth2 > > > > And yet, during the machine's POST (which can verify by the PXE boot up > of > > each device), it correctly enumerates the ethernet devices as: > > Port1 > > Port2 > > PCIe card > > > > So where and why is the order changed when the kernel kicks in and start > > booting the machine? And how can I stop it, or change its behavior? I'm > not > > seeing any 'renaming' going on in dmesg like I sometimes find. So > something > > is causing this and I can't figure it out. > > > > Yeah, my understanding is that the kernel does not really trust all the > information that the BIOS tells it and probes for the network devices > itself. > > I'm thinking, since you are using kickstart and PXE boot, you're not going > to know the HWADDR for your NICs before hand, but you probably do have a > predictable pci bus layout. > > So grab pciutils package and run: > > lspci | grep Ethernet > > I get something like > > 00:0a.0 Ethernet controller: NVIDIA Corporation MCP67 Ethernet (rev a2) > 01:06.0 Ethernet controller: Intel Corporation 82541PI Gigabit Ethernet > Controller (rev 05) > 01:07.0 Ethernet controller: Intel Corporation 82541PI Gigabit Ethernet > Controller (rev 05) > > The first number is the bus id which is going to be consistent across > machines with the same mainboard and nic layout. > > So I can make a persistent-net.rules file like: > > ACTION=="add", SUBSYSTEM=="net", BUS=="pci", ID=="0000:00:0a.0", > NAME="eth0" > ACTION=="add", SUBSYSTEM=="net", BUS=="pci", ID=="0000:01:06.0", > NAME="eth1" > ACTION=="add", SUBSYSTEM=="net", BUS=="pci", ID=="0000:01:07.0", > NAME="eth2" > > > Hope this helps. > > K > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos > >