MAC address duplicate

slimx3m · 06-19-2009, 06:59 AM

i have a small problem with UT VMWare on windows. it seems to me that there is a MAC address duplicate on my network. does any body know how i could change and update the mac address of the NIC in VMWare?

thanks in advance

sky-knight · 06-19-2009, 09:09 AM

The windows install hacks the arp caches of all your machines to take over the IP address that belongs to your router. This trips the IP duplication code in windows, that error is normal. Just ignore it.

slimx3m · 06-19-2009, 09:38 AM

thanks for this information sky-knight. i just started receiving this error on my UNIX server and it has been scrolling down giving me that warning like crazy.

dmorris · 06-19-2009, 11:39 AM

Yes, you can just ignore it.
In the next version we won't be filtering the host that runs untangle so this error message will go away.

slimx3m · 06-22-2009, 06:09 AM

@dmorris,
sorry that i didn't specify well enough. i have UT running on a windows host machine and the one that is giving me the error is my UNIX server. apparently there is a duplication in the MAC address on the network and that is why i am receiving that error message.

any other thoughts?

sky-knight · 06-22-2009, 08:45 AM

Yes... there IS a duplication of a mac address.

That is the way re router works... it sends hacked arp broadcasts out to your lan so that all than lan computers think the re-router has the mac address for the gateway. Then it sends a directed arp unicast at the router to make it think that the UT has all the macs for every ip on the lan.

The only way to get rid of this error on your unix station is to get rid of re-router.

slimx3m · 06-23-2009, 07:01 AM

thnx for the useful information sky-knight

.

06-19-2009, 06:59 AM	#1 (permalink)
slimx3m Untanglit Join Date: Dec 2008 Posts: 27	MAC address duplicate i have a small problem with UT VMWare on windows. it seems to me that there is a MAC address duplicate on my network. does any body know how i could change and update the mac address of the NIC in VMWare? thanks in advance

06-19-2009, 09:09 AM	#2 (permalink)
sky-knight Join Date: Apr 2008 Location: Phoenix, AZ URLs submitted: 7 Posts: 7,722	The windows install hacks the arp caches of all your machines to take over the IP address that belongs to your router. This trips the IP duplication code in windows, that error is normal. Just ignore it. __________________ Intouch Technology Rob Sandling, BS:SWE, MCP Office: 480-272-9889 rob@intouchtechllc.com

06-19-2009, 11:39 AM	#4 (permalink)
dmorris Untangle Junkie Join Date: Nov 2006 Location: San Mateo, CA URLs submitted: 10 Posts: 5,166	Yes, you can just ignore it. In the next version we won't be filtering the host that runs untangle so this error message will go away. __________________

06-22-2009, 08:45 AM	#6 (permalink)
sky-knight Join Date: Apr 2008 Location: Phoenix, AZ URLs submitted: 7 Posts: 7,722	Yes... there IS a duplication of a mac address. That is the way re router works... it sends hacked arp broadcasts out to your lan so that all than lan computers think the re-router has the mac address for the gateway. Then it sends a directed arp unicast at the router to make it think that the UT has all the macs for every ip on the lan. The only way to get rid of this error on your unix station is to get rid of re-router. __________________ Intouch Technology Rob Sandling, BS:SWE, MCP Office: 480-272-9889 rob@intouchtechllc.com

06-19-2009, 09:38 AM	#3 (permalink)
slimx3m Untanglit Join Date: Dec 2008 Posts: 27	thanks for this information sky-knight. i just started receiving this error on my UNIX server and it has been scrolling down giving me that warning like crazy.

06-22-2009, 06:09 AM	#5 (permalink)
slimx3m Untanglit Join Date: Dec 2008 Posts: 27	@dmorris, sorry that i didn't specify well enough. i have UT running on a windows host machine and the one that is giving me the error is my UNIX server. apparently there is a duplication in the MAC address on the network and that is why i am receiving that error message. any other thoughts?

06-23-2009, 07:01 AM	#7 (permalink)
slimx3m Untanglit Join Date: Dec 2008 Posts: 27	thnx for the useful information sky-knight .