Hi All,

While mucking about with the virtual network interface settings of a guest under virt-manager, the default mac address of the guest has somehow been applied to the host. It was an experiment with one of the macvtap/passthrough options which did it, I believe.

I wouldn't expect a VM configuration change to be able to re-write the host NIC's ROM, so am running on the assumption that spoofing has been applied to the host somewhere. The question is... where?

rc.inet1.conf is unchanged, has no HWADDR entries in it, and in any case shouldn't be a factor as the host uses NetworkManager. udev's 70-persistent-net.rules is also unchanged, and contains the correct mac address of the host. /etc/NetworkManager appears to contain nothing of consequence.

Any suggestions as to where else to look in order to put a cease to this? As a workaround I have been re-assigning the original mac address via ifconfig, but the change only holds until the next re-boot.

Check the file /etc/sysconfig/network-scripts/ifcfg-<ifname> for a MACADDR line and remove it.

Just to be sure. Boot to a live cd and see if the mac is really burned. I suspect it is just settings as smallpond suggests.

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No /etc/sysconfig/... on this system; should have mentioned that it's Slackware, which is why I first checked for modifications to scripts in /etc/rc.d.

After a live cd boot it looks as though the new MAC address was burned to the NIC. I can work with it, but find it very odd that configuration tools for a virtual pc have this ability.

Thanks for the update.

More than odd, worrisome.