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CE500, Users received duplicate IP address messages

Last night I moved a small network over to three Express500 switches. I have two servers, and one user that intermittently shows Event Viewer messages of "duplicate IP address found" and gives the MAC address of itself with the exception of the first two bytes. Examples

User with with a MAC of 0011.439f.79c8

displays an EV duplicate IP address from MAC 9c11.439f.79c8.

The two servers intermittently do the same: Example: Real MAC address 000d.6015.1c04, Its Event viewer message shows duplicate IP address from MAC:


I have her port set pu for "desktop + IP Phone", although I haven't place her phone there yet.

The other two servers are set up as "servers-standard". With the servers, I pulled their cat5 cables out, cleared IP ARP and tried to PING the address from my router, but could not. I'm 99.9999% positive these are not duplicate IP addresses. Ports on the desk top, server and switches are all set up for auto/auto. As this is my first time working with the Express 500, I'm wondering whether the MAC address of beginning of the ethernet frames is being corrupted??!! Any ideas?




Re: CE500, Users received duplicate IP address messages

The MAC addresses shown in the Event Viewer doesnot seems to be real. Are you using any application that could generate such temporary MAC addresses? These smartport roles should not cause any trouble.

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Re: CE500, Users received duplicate IP address messages

Are you sure you have 12.2(25)SEG on the CE-500s? I'd start there. You can also check the ARP table in the 500 via the 'exec' web interface, http://switchipaddress/level/15/exec (and follow the prompts)

which should help a bit...

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