Re[3]: [gentoo-user] MAC addresses

[Sergey A. Kobzar]

Thursday, April 30, 2009, 10:48:06 PM, Sergey wrote:

> Thursday, April 30, 2009, 10:34:28 PM, Daniel wrote:

>> On Thu, 2009-04-30 at 18:09 +0300, Sergey A. Kobzar wrote:
>>> Hello.
>>>
>>> I have Gentoo server Linux 2.6.27-gentoo-r8 x86_64 connected to
>>> LinkSys switch. It has 2 NICs onboard:
>>>
>>> eth0      Link encap:Ethernet  HWaddr 00:15:17:1a:6e:6c
>>> eth1      Link encap:Ethernet  HWaddr 00:15:17:1a:6e:6d
>>>
>>> 2nd NIC is connected to LinkSys switch, but the switch shows that
>>> device connected to the port has other MAC address:
>>>
>>> VLAN ID   VLAN 3
>>> MAC       00:15:17:1a:6e:6f
>>> Port      g31
>>>
>>> The difference in last symbol.
>>>
>>> How is it possible?

>> I suggest, to first check which device/OS is telling the truth. Use
>> wireshark to capture and review some traffic. Maybe this helps analyse
>> the situation.


> I've started this thread because connection to the server is unstable
> and I see such reports from other servers:

> +arp: 10.11.1.203 moved from 00:15:17:1a:6e:6f to 00:15:17:1a:6e:6d on em1
> +arp: 10.11.1.203 moved from 00:15:17:1a:6e:6d to 00:15:17:1a:6e:6f on em1
> +arp: 10.11.1.203 moved from 00:15:17:1a:6e:6f to 00:15:17:1a:6e:6d on em1
> +arp: 10.11.1.203 moved from 00:15:17:1a:6e:6d to 00:15:17:1a:6e:6f on em1
> +arp: 10.11.1.203 moved from 00:15:17:1a:6e:6f to 00:15:17:1a:6e:6d on em1

> BIOS tells that NIC1 has 00:15:17:1a:6e:6c MAC and NIC2 has
> 00:15:17:1a:6e:6d. It's strange that 00:15:17:1a:6e:6d MAC is common
> for both NICs.


I think this happens because Intel NIC Teaming is enabled for the NIC.
Is it possible check this using Linux and disable teaming if needed?


-- 
Sergey