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Duplicate IP address message


We are facing some strange problem with duplicate ip address message. Our set up is simple. We have two 2950 switchces having 3 vlans configured on each. Connected by a trunk. configuration of each switch same except management vlan ip address. one interface from each Vlan is connected to a firewall interface. ( dmz1, dmz2,dmz2 ). And all servers having two ethernet cards are configured in bridge mode are connected to each switch seperately. ( each server one ethernet interface is connected to one swicth and second ethernet connected to second swicth both interface of swicth are in same Vlan ). This is very strainght forward set up which is working ok at all locations. Except one which we are debugging now.

Secondly we have found that, when ip address above certain value is configured the message of duplicate address starts flashing.

When we check cdp neighbor on swicth it is learning neighboring swicth from all servers bridge interfaces. and not only from trunk.

Where is the problem ?

Thanx in advance.


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Re: Duplicate IP address message

Hi, wrt to the first problem, you may have another switch beween server and 2950.

Then if you trace the duplicated IP by mac to the systems it indicates, you may find that something is wrong in there.

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