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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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