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

7920 IP Phones - Duplicate IP Address

When I configure a 7920 phone it often gives the error 'duplicate ip'. I can reset both the new phone, and the other phone already on the network with the same IP and one of them eventually gets another IP. This has only started happening over the last month or so. I can't find anything in DHCP that seems odd. I found other questions about this on here from last year, but never came to a conclusion.

Any help would be much appreciated.

Thanks!

8 REPLIES
Gold

Re: 7920 IP Phones - Duplicate IP Address

What are you using as your DHCP Server ??

Community Member

Re: 7920 IP Phones - Duplicate IP Address

This DHCP scope, along with all of our others that seem to be behaving correctly, are set up on the AD server, not one of the call manager servers.

Community Member

Re: 7920 IP Phones - Duplicate IP Address

Do you have one of the phones hard coded with an IP?

Community Member

Re: 7920 IP Phones - Duplicate IP Address

No, all the phones are set to DHCP. This seems to be happening every time I configure a new device. It pulls an IP that is already on another phone, then I have to reset them both.

Community Member

Re: 7920 IP Phones - Duplicate IP Address

I'm experiencing the exact same scenario, any resolution yet?

PS - I'm only have complaints from technicians at our site that uses WiSM, so far.

Silver

Re: 7920 IP Phones - Duplicate IP Address

Melissa

Are you using a Cisco IOS router to perform the DHCP address allocation?

How many DHCP servers are there on your network?

let us know hey...

Ajaz

Community Member

Re: 7920 IP Phones - Duplicate IP Address

We are only using 1 DHCP server.

Community Member

Re: 7920 IP Phones - Duplicate IP Address

Try running a packet sniffer on your network (Wireshark or ethreal).

1026
Views
0
Helpful
8
Replies
CreatePlease to create content