duplicate MAC address

[Printaporn_1]

Hi,

I got duplicate MAC address on B180L
# lanscan
Hardware Station Crd Hardware Net-Interface NM MAC HP DLPI Mjr
Path Address In# State NameUnit State ID Type Support Num
8/0/1/0 0x0010836558AE 1 UP lan1 UP 4 ETHER Yes 119
8/0/20/0 0x0010836558AE 0 UP lan0 UP 5 ETHER Yes 115
-------------
# ioscan -fnC lan
Class I H/W Path Driver S/W State H/W Type Description
=====================================================================
lan 1 8/0/1/0 btlan5 CLAIMED INTERFACE PCI(10110019) -- 1
lan 0 8/0/20/0 btlan3 CLAIMED INTERFACE PCI(10110019) -- Built-
in #3
/dev/ether0 /dev/lan0
------------------
# ifconfig lan0
lan0: flags=863
inet 10.196.16.189 netmask fffffc00 broadcast 10.196.19.255
# ifconfig lan1
lan1: flags=863
inet 10.3.112.1 netmask ff000000 broadcast 10.255.255.255

--------------
# netstat -rn
Routing tables
Destination Gateway Flags Refs Use Interface Pmtu PmtuTime
10.3.112.1 127.0.0.1 UH 0 1506 lo0 4608
10.196.16.189 127.0.0.1 UH 18 601122 lo0 4608
127.0.0.1 127.0.0.1 UH 0 36784 lo0 4608
default 10.196.16.1 UG 0 0 lan0 1497
10 10.3.112.1 U 2 423032 lan1 1500
10.23 10.196.16.9 UG 0 0 lan0 1497
10.196.16.0 10.196.16.189 U 16 22161 lan0 1497
32.76 10.196.16.9 UG 9 648152 lan0 1497
----------------

then this cause we cannot ping other segment across default router whereas other hp-ux in same segment can do.

I notice there are lan1 MAC in /etc/rc.config.d/hppci100conf

HP_PCI100_INTERFACE_NAME[0]=lan1
HP_PCI100_STATION_ADDRESS[0]=0x0010836558AE
HP_PCI100_SPEED[0]=
#HP_PCI100_DUPLEX[0]=

can I change this , why it happen ?
or DUP MAC is not problem.

please advise.

[Chin Guan · Accepted solution]

Duplicate Mac address is definitely not good. Try to :

grep 0x0010836558AE /etc/rc.config.d/

to check if there are other files having this MAC address in it.

When system bootup, startup script execute lanadmin command and assign the MAC address specified in the configuration files and overwrites the original MAC address. If you remove them and reboot, lanscan should show you the original MAC address of the card.

I also notice that netmask for both lancards are different. Can you verify are they correct? That could be another potential problem?

Can you ping to your default router?

[Printaporn_1]

Hi Chin Guan,

thanks friend , not wonder , I am Aum , your old friend.

I found duplication in hpbase100conf
but I cannot reboot that workstation now , will modify and see ?

my e-mail:sangdara@celestica.com

keep in touch.
Aum
(this forum better than log case ;-) )

[Thierry Poels_1]

Hi,
duplicate MAC addresses is suposed to be impossible. MAC addresses are hardware addresses, and should be unique (as far as I believe they should be unique world-wide for any network device, not?).
I don't know how things got wrong at your site, but one of the network interfaces got the wrong MAC addres in its /etc/rc.config.d-file. You mentionned hppci100conf, but there is a similar file for your built-in network interface.
Try to find out which one is wrong (maybe stm will help). Maybe you'll need to remove the 2nd interface card, delete it's settings, get the built-in interface working, and then reinstall the 2nd interface card.
good luck,
Thierry.

[Juan González]

Hi,
duplicate MAC address doesn't have to be a problem if you are sure that they are in differents LANs. In fact, I know that, by default, in Solaris (E250, E450) the NICs not built in inherits the MAC address of the built in one. I think it is done to identify the machine with is MAC address.

In your case, as Chin Guan pointed you have a strange network configuration. Your server is in two LANs 10.196.16.189 and 10.0.0.0, so the former is embedded in the last. If this is really your configuration you must change the MAC address as Chin Guan explained.
Best regards

[John Bolene]

Not impossible but highly improbable to have duplicate MAC addresses even from the factory.
On our 2000 X-terms all ordered at the same time, we had 3 dups.

It was explained to me that this is done at the factory and burned into the rom.

The guy doing the burning has to keep track of each address used and increment it for the next one. If he gets distracted by lunch, going home, etc, he may forget to increment the next one.

As has been said, check those /etc/rc.config.d/netconf files, there is a software configuration place to override the hardware mac.

Our dup X-term roms had to be replaced since it was burned into them.