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Duplicate IP Address

John N

I have two issues.  One of my catalyst 4948 switches (VTP setup) is popping up a duplicate address on VLAN 302 sourced by (mac address) 0000.0000.0000.  Now I was able to find the other switch which had the same IP address and change the IP on the offending switch.  However the switch I am trying to upgrade keeps popping the error message even after changing the IP on the other switch.  What I then did was clear the ARP table and in doing so I believe I might have actually deleted (not from the switch) but when I do a show vlan - none of the VLANS that were show up even though they are connected as before.  Anyone have any ideas?  


To summarize - Need to get rid of this annoying popup for duplicate IP address and when i run a show ip command I need the switch to show the VLANS that were there before.  



5 Replies 5

Thank you but still confused on how to go about it.  Any idea on how to get my VLANS to show up when I enter show vlan on of the switches? 


 clear arp table shouldn´t delete the vlan database. The switch probably have software issue and if you were about to upgrade, why dont you do ahead and do so.  The upgrade can fix both problems.


Yes that was my plan of action was to upgrade and see if it clears.  Thank you for all your help.  However on the other switch I can't put in a command without getting a popup for duplicate IP address.  Should I SSH where I dont get popups and do the upgrade that way? Or is there a clear cut way to get rid of this popup? 

@John N  

 That´s could be a plan of action.  You can try that an let me know

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