Re: Blocking cdp messages by device

thontz · ‎03-31-2003

We have a MAN with 7 routers connected to a shared 100MB fiber ring. We need to run cdp to see the connections between these devices. The problem is our service provider has a Cisco network management device that can only run at 10 MB/half duplex. All of our routers on the MAN see this device through cdp and report a duplex mismatch with this device. This amounts to approximately 1000 messages per day per device. Is there any way I can block cdp messages from this device(i.e IP or MAC address) without entirely disabling cdp? Our provider has turned off cdp but we still see his device. Thanks.

srego4 · ‎03-31-2003

disable cdp (on your routers ) on the INTERFACE facing the service providers switch.

You shd. be doing this anyway as this is better for your network security.

thontz · ‎04-08-2003

This worked fine on our 6509, 3725, 4006, and 2651 routers. When I disabled cdp on our 3550 it no longer appeared in my Campus Manager Layer 2 view. Any suggestions? Thanks.

srego4 · ‎04-14-2003

Did you disable cdp only on the interface facing the service provider or did you disable it globally. If you did the former, and it still does not show up, then try adding it in your seedfile.

thontz · ‎04-14-2003

Yes, I disbaled cdp only on the interface facing the service provider. Even when the 3550 was added to the seed file it still did not show up in Campus Manager. Any other suggestions would be greatly appreciated.

srego4 · ‎04-14-2003

Try enabling cdp globally and interface level and see if you see the device again. If not check if you have any acl's that maybe blocking this device.

Before you do that you could also telnet to the device and do a sh cdp nei det. check the address' if any.

Also you mentioned that your service provider has a network "Management" device that is 10 half. I am a bit confused when you use that term. Anyway if it is a switch or router then you shd. be setting up your interface facing it with 10 half as well.