multiple mac and ip-adresses on ACS appliance

Unanswered Question

Our network is in 172.25.x.x range, we have 2 ACS appliances, with ip-adresses and .72

Our fluke network scanner reports a duplicate ip-address on the switchports where the acs appliances are connected to.

The duplicate ip-address is, but we can't find this ip-address anywhere in the ACS. The address is even reachable, I put my pc in the same range .2 and I could ping the ip-address.

Does someone know where to find/delete/change those strange ip-addresses in our ACS? We use software level 4.1 on windows 2000. We only connected 1 interface of the machine, the extra ip-address is on the same interface as the ip-address we use, there are also multiple mac-addresses shown on the switchport.



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Overall Rating: 1.3 (3 ratings)
Jagdeep Gambhir Tue, 08/21/2007 - 04:27
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Logon to acs---> Network confiuration----> Search IP ---->192.x.x.x and see if it finds any.

It could be possible that 192 IP is still there from old configuration of acs.

If you can find it, delete it.



Jagdeep Gambhir Tue, 08/21/2007 - 05:28
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If you bring appliance off the network , can you still ping 192 ip ?



The original mac-addresses are 00-16-36-eb-2c-7c and 00-16-36-91-9c-6b

And on the same network interface of both acs appliances the analyzer also finds mac-addresses 00-16-36-eb-30-c9 and 00-16-36-91-a0-fe.

So they are almost similar, but 4 last digits are different. It is strange that I can't find any of it in the config.

Jagdeep Gambhir Mon, 09/03/2007 - 06:33
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These mac belongs to Quanta Computer Inc. I would suggest you to open a TAC case.

Also please avoid rating on the troubleshooting conversation, as we all know that these initial conversation is not going to help !


johnaceti Thu, 04/17/2008 - 07:43
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I found this post while researching. We are working on the same trouble.

Even log shows dupl IP from an unknown MAC

Same ACS version.

johnaceti Fri, 04/18/2008 - 05:06
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We fixed the problem with the ACS sending out duplicate IP's.

Install instructions said to use bottom ethernet interface (NIC1) but we had originally used and configured the top.

We moved the cable to the bottom NIC.

Restarted the unit

Using the serial cable - reprogrammed the IP/mask/gw/DNS etc using the set ip command.

Viola, no more problems :-)

6dchovatia Mon, 01/14/2008 - 20:30
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I am having the same issue with two 4.1 appliances. Did you have any luck with resolving this problem?

Seems like a bug, but TAC has not been able to help much. I have applied all the upgrades and pathes for 4.1.

6dchovatia Tue, 01/15/2008 - 18:02
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TAC had no specific solution and hence we went through all the published patches for acs 4.1 release. TAC is going to RMA our appliances. Hopefully we will not have the same problem with the new appliances.

It is puzzling where the IP is coming from. Given that the the interface on the appliance has 2 MAC addresses, it seems that the IP is configured in the underlying windows OS, however the OS part of the appliance is locked out.


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