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New Member

Help with CDP


I have a question about CDP. We are converting our routers to a frame to ATM solution. Since we've been cutting them, I noticed CDP no longer works on the serial interfaces (it worked fine on the frame to frame config). I was just curious to see if I am maybe missing something. CDP is enabled on all interfaces and it is sending packets every 60 seconds. Any input would be greatly appreciated. Thanks!

New Member

Re: Help with CDP

I can't find any documentation to support it but I have been told a couple of times that CDP does not work with ATM (be it pure ATM or Fratm)

Cisco Employee

Re: Help with CDP

Check and make sure that your switch (providing the interworking function) supports CDP in that mode. The switch might be dropping CDP as unknown protocol

New Member

Re: Help with CDP

CDP requires SNAP Support.

Works in the Datalink layer

media and Protocol Independant

but i am really wondering if it would work in a framerelay setup like FRSWX Switch... to another router cause FRamerelay is a non broadcast medium and CDP uses Multicast address so it wouldnt work

in a framerelay connection..

Pls can anyone who knows well clarify.. i just spoke on what i think is right ! ..


New Member

Re: Help with CDP

Check if the interface supports CDP with (config-if)#cdp enable. If it is not supported you will get:

"% CDP is not supported on this interface, or for this encapsulation"

You can also try and use "sh atm pnni neigh"

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