invalid MAC addresses?

[Oliver Lehmann]

Hi,

when I update the BIOS of my new AM3+ Mainboard, The
MAC address of my re0 card gets changed from
c8:60:00:60:3b:c6 to ed:0b:00:00:e0:00 With this
change, no communication with any other FreeBSD system
is possible.

When I try to ping another FreeBSD system, all I can see
on the system I ping with tcpdump is:

# tcpdump -i fxp0 -n -vv
tcpdump: listening on fxp0, link-type EN10MB (Ethernet),
capture size 65535 bytes
17:06:50.689424 IP (tos 0x0, ttl 120, id 3004, offset 0,
                 flags [none], proto ICMP (1), length 84)
     10.111.72.186 > 10.111.72.185: ICMP echo request, id
                 47626, seq 0, length 64
17:06:50.689488 ARP, Ethernet (len 6), IPv4 (len 4),
                 Request who-has 10.111.72.186 tell
                 10.111.72.185, length 28
17:06:50.689758 ARP, Ethernet (len 6), IPv4 (len 4),
                 Reply 10.111.72.186 is-at
                 ed:0b:00:00:e0:00, length 46

But the MAC address gets not stored in the ARP cache of
the pinged system and now answer is sent back to the
pinging system:

# arp -n 10.111.72.186
? (10.111.72.186) at (incomplete) on fxp0 expired [ethernet]


10.111.72.186 is the system with the changed BIOS/MAC address
from where I issued a ping to 10.111.72.185

Both systems are connected together with a crossover cable.

When I attach the system with the changed MAC adress to a
switch, and issue dhclient command, the system which does
not answered my ping before, hands out an IP adress to this
system (it is my DHCP server)
Then again - ping does not work to any FreeBSD system
attached to this switch. Pinging a Windows system works and
I can even ping my network printer attached to this switch.

So I wonder what is wrong with this MAC Address that FreeBSD
does not like it? :(

   Greetings, Oliver