Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

Detection of Duplicate address

Hi,

We are having some kind of weird problem of duplicate address message appearing on servers. We are having two 2950 switches connected to each other by trunk. Vlans are configured on each switch. Both switch configuration are identical. Each server ( IBM-AIX ) is having two ethernet cards and each card is connected to each swicth in the same VLAN. In all there are 3 VLAN's in each switch. Similar kind of setup is working fine at many of our locations. But here servers flash duplicate ip address message, very much surprising !!

Second thing we found out that if we check cdp neighbor , each switch learn other switch from each server as if second swicth is directly connected vis server.

Can we moniter on swicth what is the problem. ?

Please share similar experience or suggest a solution.

Thanx in advance

Subodh

1 REPLY
New Member

Re: Detection of Duplicate address

do you have switchport security implemented in your switches?

have you verified that that ip address in use by your server is not being used anywhere else?

the error message that you see on your server should also indicate the mac address of the conflicting device. is that mac address familiar to you?

can you telnet to your switch and track down which port that mac is coming from.

can you also post a config.

good luck

hieu

233
Views
0
Helpful
1
Replies
CreatePlease login to create content