So I just finished doing a fresh install of CentOS 6.3. The machine has three ethernet ports in it: one on the motherboard (VIA Rhine), and two add-on cards, an Intel Pro100 and an old SMC1255TX. When CentOS comes up, this is what I see in the dmesg output:
# dmesg | grep eth e100 0000:00:08.0: eth0: addr 0xf6043000, irq 16, MAC addr 00:02:b3:be:02:87 eth1: ADMtek Comet rev 17 at MMIO 0xf6040000, 00:4c:69:6e:75:79, IRQ 17. udev: renamed network interface eth0 to rename2 udev: renamed network interface eth1 to eth3 udev: renamed network interface rename2 to eth1 eth0: VIA Rhine II at 0xf6042000, 00:16:17:17:22:8e, IRQ 23. eth0: MII PHY found at address 1, status 0x786d advertising 05e1 Link 45e1. eth0: link up, 100Mbps, full-duplex, lpa 0x45E1 eth0: no IPv6 routers present
So, according to the musical playing going on there, the result is:
eth0: VIA Rhine eth1: IntelPro 100 (originally comes up as eth0 but gets renamed eth1) eth3: SMC1255TX (originally comes up as eth1 but gets renamed eth3)
Here's my issue:
In udev rules (/etc/udev/rules.d/70-persistent-net.rules I see:
# PCI device 0x1113:0x1216 (tulip) SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:4c:68:6e:ff:ff", ATTR{type}=="1", KERNEL=="eth*", NAME="eth2"
# PCI device 0x8086:0x1229 (e100) SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:02:b3:be:02:87", ATTR{type}=="1", KERNEL=="eth*", NAME="eth1"
# PCI device 0x1106:0x3065 (via-rhine) SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:16:17:17:22:8e", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"
# PCI device 0x1113:0x1216 (tulip) SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:4c:69:6e:75:79", ATTR{type}=="1", KERNEL=="eth*", NAME="eth3"
Question is, where did the first tulip interface come from? That's not any of the interfaces on the machine, it doesn't match the MAC address of any of the interfaces, so where'd it come from?
Furthermore, when I look in /etc/sysconfig/network-scripts/ifcfg-eth2, the HWADDR there is the same as the first interface listed above. But again, it's not in dmesg's output. As far as I can tell, it's a ghost interface ...
What gives, and how can I get rid of it so that the proper interface gets the eth2 spot?
A