I have a simple xen project 4.1 setup running on debian wheezy dom0. I have noticed during a network scan that a domU gateway returned 2 mac addresses for the same IP. One MAC being the expected, XenSource Vendor, address which is randomly generated when the domU is created. The other is the hardware, SuperMicro Vendor, mac address.
In the dom0
./interfaces, i initialize the physical interface as
manual. I initialize the bridge as
static and add the physical interface to it.
In my domU
.cfg I declare the previously defined dom0 bridge as an interface. At this point, from my understanding, any packet generated on the domU is tagged with the auto-generated(no, i did not explicitly declare a MAC in the .cfg), XenSource Vendor, MAC address.
How is it possible for the real SuperMicro MAC address to show up?
This stems from my attempts to diagnose an intermittent connectivity problem, which im now led to believe may be some kind of arp cache poisoning from my xen machine.
eth1 Link encap:Ethernet HWaddr 0c:c4:7a:00:c6:25 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:852986 errors:0 dropped:0 overruns:0 frame:0 TX packets:1295501 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:152249020 (145.1 MiB) TX bytes:1616503376 (1.5 GiB) Memory:f7100000-f7180000
bridge name bridge id STP enabled interfaces xenbr0 8000.feffffffffff no vif6.0 xenbr1 8000.0cc47a00c625 no eth1 vif6.1 xenbr2 8000.feffffffffff no vif6.2 vif7.0 xenbr3 8000.6805ca213b95 no eth2 vif6.3
eth1 is the interface in question. Thx.