From: Hobbs (deadheadblues@gmail.com)
Date: Wed Aug 06 2008 - 22:12:29 ART
Hello,
I have been working on this all day, I have got most of it to work and have
one more little roadblock. The odd things about this is that it works one
way. cdp, stp, lacp were all being tunneled successfully from R3 to R4.
debug showed that R4 was receivng packets from R3 over the tunneled port.
However the reverse is not true.
[CAT4]20--------20[CAT1]24--------24[CAT2]20--------20[CAT3]
The numbers above are the FastEthernet ports.
Cat4 and cat3 should see each other as CDP neighbors.
One thing about this solution is:
ports 24: mode dot1q-tunnel
ports 20 on cat1 and cat2: mode access
ports 20 on cat3 and cat4: mode trunk
Before I show the configs, I'll show that cat4 does see cat3 over port 20:
CAT4#show cdp neighbors | inc CAT3
CAT3 Fas 0/24 132 S I
WS-C3560-2Fas 0/24
CAT3 Fas 0/23 132 S I
WS-C3560-2Fas 0/23
CAT3 Fas 0/20 132 S I
WS-C3560-2Fas 0/20
However, CAT3 is not showing CAT4:
CAT3#show cdp neighbors | inc CAT4
CAT4 Fas 0/24 145 S I
WS-C3560-2Fas 0/24
CAT4 Fas 0/23 145 S I
WS-C3560-2Fas 0/23
It seems I just need to mirror the config that is working but I am. I'll
show the ports in order from left to right. Pay no mind to lacp right now,
as I do not have it on the end ports. Just the CDP I'm trying to get going.
*CAT4*:
interface FastEthernet0/20
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 1-12,14-4094
switchport mode trunk
*CAT1*:
interface FastEthernet0/20
switchport access vlan 43
switchport trunk encapsulation dot1q
switchport mode access
l2protocol-tunnel cdp
l2protocol-tunnel stp
l2protocol-tunnel vtp
l2protocol-tunnel point-to-point lacp
no cdp enable
interface FastEthernet0/24
switchport access vlan 43
switchport trunk encapsulation dot1q
switchport mode dot1q-tunnel
l2protocol-tunnel cdp
l2protocol-tunnel stp
l2protocol-tunnel vtp
l2protocol-tunnel point-to-point lacp
no cdp enable
*CAT2*:
interface FastEthernet0/24
switchport access vlan 43
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 1-12,14-4094
switchport mode dot1q-tunnel
l2protocol-tunnel cdp
l2protocol-tunnel stp
l2protocol-tunnel vtp
l2protocol-tunnel point-to-point lacp
no cdp enable
interface FastEthernet0/20
switchport access vlan 43
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 1-12,14-4094
switchport mode access
l2protocol-tunnel cdp
l2protocol-tunnel stp
l2protocol-tunnel vtp
l2protocol-tunnel point-to-point lacp
no cdp enable
*CAT3*:
interface FastEthernet0/20
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 1-12,14-4094
switchport mode trunk
Now remember that this works in one direction from
cat3-->cat2-->cat1-->cat4.
The breakdown is from cat4--->cat3, specifically between cat4 and cat1 I
believe. This is because a show l2protocol-tunnel shows 0 encapsulated
packets for CDP on port 20.
any ideas? remember it works one way!
thanks,
Blogs and organic groups at http://www.ccie.net
This archive was generated by hypermail 2.1.4 : Mon Sep 01 2008 - 08:15:29 ART