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To: freebsd-questions@freebsd.org, "Mike Jeays" <mike.jeays@rogers.com>
Subject: Re: MAC address changed
References: <20140407201832.5f89976b@europa>
Date: Tue, 08 Apr 2014 03:05:40 +0200
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From: "Michael Ross" <gmx@ross.cx>
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On Tue, 08 Apr 2014 02:18:32 +0200, Mike Jeays <mike.jeays@rogers.com>  
wrote:

> More hardware related than FreeBSD - I have an old Pentium 4 with
> a Realtek network card, that I use for backups. I had a power failure
> yesterday, and on reboot, the MAC address on the card has changed from
> 00:e0:18:94:55:89
> to
> 00:e0:18:94:e0:89
>
> Anyone have an explanation for this surprising behaviour?

RealTek has produced really bad cards for a while,
you may have one of those ( especially if it is from the Pentium 4 days ).

http://www.fefe.de/linuxeth/realtek.txt ( from 2001 )
"For example RealTeks tend to change their MAC-Address wihtout motivation."

I've never noticed MAC changes, but I've had bad performance problems
with 8139 cards -- maxing out at ~70MBit.
Best to use another one, really.


Michael