> Maybe because you are looking at the bridge's mac and not the > ethernet's which would be peth0. No I am not. dmesg shows the kernel messages at boot and it is looking at the physical device, let's not get distracted, the issue is clear in this regard. As I previously stated, this happens even when uninstalling XEN and booting off the non-XEN kernel since the install of XEN. > indeed, AFAIK all hardware adapters start with 00. This must have been set > in the BIOS or with a boot option or in the network config. This was helpful, gave me places/incentive to continue looking. In /etc/sysconfig/network-scripts/ifcfg-eth1 I found: # Realtek Semiconductor Co., Ltd. RTL-8169 Gigabit Ethernet DEVICE=eth1 BOOTPROTO=none HWADDR=00:40:F4:CE:E6:7B So now I know what the original MAC address was. Here is where it gets interesting. The following file was modified at the date/time that the XEN kernel was first booted: /etc/sysconfig/hwconf and it has fe:ff:ff:ff:ff:ff for BOTH network adapters: desc: "Realtek Semiconductor Co., Ltd. RTL-8169 Gigabit Ethernet" networfe:ffddr: fe:ff:ff:ff:ff:ff vendorId: 10ec deviceId: 8169 subVendorId: 10ec subDeviceId: 8169 pciType: 10 desc: "Intel Corporation 82562EZ 10/100 Ethernet Controller" network.hwaddr: fe:ff:ff:ff:ff:ff vendorId: 8086 deviceId: 1050 subVendorId: 8086 subDeviceId: 303a Everything I'm finding is re-enforcing my original theory that XEN modified the hwaddr of this NIC. The question continues to be what caused this and how to change it back. Given this is a stock system, I have to believe others must have/may run into this issue. Brett _______________________________________________ CentOS mailing list CentOS@xxxxxxxxxx http://lists.centos.org/mailman/listinfo/centos