[CentOS] Forcing ifcfg-eth0 to use the same nic in multi nic machine

Les Mikesell lesmikesell at gmail.com
Wed Aug 15 12:55:41 UTC 2007


Lanny Marcus wrote:
> On 13 August 2007, Johnny Hughes <johnny at centos.org> wrote:
> <snip>
>> How can 2 nics from different companies have the same mac address ....
>> I don't think that is possible.
>> each card needs a separate MAC address, at least the way I understand
>> networking.
> 
> I agree with Doug and Johnny. My belief is that every NIC in the world
> is supposed to have a unique MAC address.

Everyone believed that except DECnet which expected all cards in the 
same machine to have the same MAC.  The address should be stored in a 
ROM and initialized at startup, so it is probably a firmware or driver bug.

 > Although the OP has been using
> these boards without problems, I suspect there is a defect on the
> boards.

Yes, different block ranges are supposed to be assigned to different 
companies.  But, it shouldn't hurt anything unless both are connected to 
the same subnet which you aren't likely to want.

-- 
   Les Mikesell
    lesmikesell at gmail.com




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