Cisco - CDP Neighbor detail showing 0.0.0.0 for IP address

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Router#show cdp neighbor detail

---

Device ID: Switch1
Entry address(es):
IP address: 0.0.0.0
Platform: cisco WS-C3560-24PS, Capabilities: Router Switch IGMP
Interface: FastEthernet0/1.1, Port ID (outgoing port): FastEthernet0/24
Holdtime : 172 sec
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Why would the switch show 0.0.0.0 for an IP address?

CDP is a Layer-2 protocol. IP adres is Layer-3.

Could be there is no IP adres configured on the 3560.
Can you verify this?

I am remote so I can know for sure, but I am 90% positive I go into the switch before from an IP address...

I know you said that you were remote, but see if you can have somebody serial into the switch and verify the IP address.

I wonder just how reliable the cdp protocol is? But now that I think about it, it must be rather good because it did pick up the switch type details.

This is an odd one. Just shooting in the dark here ...but are there some security settings you can enable to hide the IP from cdp commands?


Cheers,

ZiPPy

There is nobody on site that could check this for me - they have no IT ppl...

I am not sure about the hiding IP address settings... I have not run into that.

Of course nobody is on-site! IT work isn't suppose to be easy and go your way right? hehe

Quite honestly I'm not sure about the hidden setting, but it was just a thought. This one is kind of bothering me, as I am sure it is bothering you. I keep going back to the notion of traffic direction. You know how you set the address of 0.0.0.0 or 0.0.0.0 0.0.0.0 and that will default to a route specified. But we are dealing with Layer 2 here. Alright I'm starting to ramble my thoughts on this thread. Sorry I can't be much more of help, if any at all. Let us know when you find the solution though, as I am quite curious.


Cheers,

ZiPPy