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Jonathan, it is a question. I am not looking for a command to make it work. it is working. please read the entire email. If my question doesn’t make sense, I can try and rephrase.
On Wed, Aug 6, 2008 at 10:42 AM, Jonathan Greenwood II wrote:
> Just turn off cdp on that particular port on CAT1 connecting to BB1. “no > cdp enable” > > > On Wed, Aug 6, 2008 at 11:37 AM, Hobbs wrote: > >> Thank you for the reply, but I am not having any configuration issues. It >> is only a question. I don’t want CAT1 to see BB1 as a neighbor, I am just >> trying to understand why it doesn’t. >> >> I am not doing dot1q tunneling >> >> >> On Wed, Aug 6, 2008 at 10:32 AM, Jonathan Greenwood II > > wrote: >> >>> You need to change the switchport mode from access to dot1q-tunnel. >>> >>> On Wed, Aug 6, 2008 at 11:27 AM, Hobbs wrote: >>> >>>> Hello, >>>> >>>> I am trying get my head around a semi-complex protocol tunneling task, >>>> but I >>>> have some questions on the basics. >>>> >>>> Here’s the topology >>>> >>>> “Near end host”: BB1 >>>> “Far end switch”: CAT2 >>>> >>>> [BB1]f0/1—–f0/11[CAT1]f0/23—–dot1q >>>> trunk—–f0/23[CAT2]f0/1—–f0/1[R1] >>>> >>>> To get cdp tunneling to work (and it does work) I enable this on CAT1 >>>> and >>>> CAT2 access ports: >>>> >>>> CAT1: >>>> interface f0/11 >>>> switchport mode access >>>> switchport access vlan 100 >>>> l2protocol-tunneling cdp >>>> no cdp enable >>>> >>>> CAT2: >>>> interface f0/1 >>>> switchport mode access >>>> switchport access vlan 100 >>>> l2protocol-tunneling cdp >>>> no cdp enable >>>> >>>> The trunk between CAT1 and CAT2 carries vlan 100 as well as others. >>>> >>>> This is what I understand so far: >>>> >>>> BB1 sends a multicast CDP packet on it’s port to CAT1. >>>> Since CAT1 has cdp tunneling enabled, it forwards it rather than >>>> processes >>>> it. Is this correct? >>>> CAT1 sends this packet out all trunk links that have vlan 100 allowed >>>> AND >>>> any access ports on VLAN100. Is this correct? >>>> The packet still has the cisco CDP destination MAC. Is this correct? >>>> The packet is dot1q tagged and sent out port fa0/23 and still has cisco >>>> CDP >>>> destination MAC address. Is this correct? >>>> >>>> Question: >>>> >>>> CAT2 doesn’t have tunneling on port fa0/23. >>>> Why doesn’t CAT2 now process this CDP packet and show BB1 has a CDP >>>> neighbor >>>> on fa0/23? >>>> Does trunking override this behavior? >>>> Does CAT2 treat this packet differently because it is a tagged CDP >>>> packet? >>>> >>>> Thanks, >>>> >>>> >>>> Blogs and organic groups at http://www.ccie.net >>>> >>>> _______________________________________________________________________ >>>> Subscription information may be found at: >>>> http://www.groupstudy.com/list/CCIELab.html
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