On 15 May 2015 at 03:51, Ashley M. Kirchner ashley@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