[Fwd:] Nvidia NICs with duplicate mac addresses

Scott Berkman scott.berkman at reignmaker.net
Fri Sep 5 09:53:28 CDT 2008

This reminds me of a story I was told a while back that there was a batch
of 3com NIC's that all went out with the same MAC from the factory.  I
never found out if that was a rumor/urban legend or the truth.  Anyone
know firsthand or have an article about that?


-----Original Message-----
From: Robert E. Seastrom [mailto:rs at seastrom.com] 
Sent: Friday, September 05, 2008 10:33 AM
To: nanog at nanog.org
Subject: [Fwd:] Nvidia NICs with duplicate mac addresses

Forwarded to NANOG in the interests of wider awareness...  having been
there and torn out my already scarce hair, duplicate MAC addresses can
really mess up your day...


Just when you thought this couldn't happen any more...

Copying from a different email list...

mac address 04:4b:80:80:80:03, was showing up in multiple places  
across the network. I googled the mac address and discovered that  
other people are having the same issue with this mac address. Below  
are some links describing the problem:

I just wanted everyone to know about this problem in case you run  
across similar slow "connectivity" issues. I believe the network card  
is made by NVIDIA.

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