Hammer, Change your breakout switch to a third party switch and it will work for you. An extreme networks switch is a good choice. CDP will pass directly thru it.
Regards, Tyson Scott - CCIE #13513 R&S, Security, and SP Managing Partner / Sr. Instructor - IPexpert, Inc. Mailto: [email protected] Telephone: +1.810.326.1444, ext. 208 Live Assistance, Please visit: www.ipexpert.com/chat eFax: +1.810.454.0130 IPexpert is a premier provider of Self-Study Workbooks, Video on Demand, Audio Tools, Online Hardware Rental and Classroom Training for the Cisco CCIE (R&S, Voice, Security & Service Provider) certification(s) with training locations throughout the United States, Europe, South Asia and Australia. Be sure to visit our online communities at www.ipexpert.com/communities and our public website at www.ipexpert.com -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of --Hammer-- Sent: Sunday, July 18, 2010 11:21 AM To: [email protected]; [email protected] Subject: [OSL | CCIE_RS] OT: Kinda OT: Fun with CDP and GNS3 ALL, I have an Ubuntu server that supports 802.1q. The server will host all my router instances and then I have 4 3560s on the back. In the middle is a 3750. The 3750 is my "breakout-switch". Meaning, the trunk comes from the Ubuntu server. All the router interfaces point to their own uniquely tagged interfaces. They go across the trunk to the breakout-switch. Then, the breakout-switch distributes them (based on tag) to the appropriate switchport which connects to the appropriate downstream 3560 port. Sample config below. Here's the fun part. I'm using l2tunnels to get CDP/STP/VTP passed. It appears to work fine but only FROM the router TO the switch. Not the other way. I think the issue is that on my breakout-switch trunk port, I can't define it as mode l2tunnel because it's mode is already trunk. So CDP makes it from the router to the switch but not vice versa. Does this make sense? If so, is there a workaround or something I may be missing? Can I somehow tell a trunk port to be a trunk but also l2tunnel for respective VLANs? I think I'm missing something here in the concept of l2tunning and what I'm trying to accomplish. ######################### .net file clip autostart = False [localhost:7200] workingdir = /home/foo/GNS3/WORKING [[7200]] image = /home/foo/GNS3/IOS/c7200-jk9o3s-mz.124-25-uncompressed.bin idlepc = 0x60678af0 ghostios = True sparsemem = True [[3640]] chassis = 3640 disk0 = 32 image = /home/foo/GNS3/IOS/c3640-jk9s-mz.124-13a-uncompressed.bin ram = 256 ghostios = True sparsemem = True idlepc = 0x607a012c [[ROUTER R-1]] console = 2101 f0/0 = nio_linux_eth:eth1.101 f0/1 = nio_linux_eth:eth1.201 x = -599.040764008 y = -249.61731573 [[Cloud S1-Fa0/1]] x = -790.521428024 y = -313.119841047 connections = R-1:f0/0:nio_linux_eth:eth1.101 [[Cloud S2-Fa0/1]] x = -791.349855149 y = -221.119841047 connections = R-1:f0/1:nio_linux_eth:eth1.201 ##################################################### breakout-switch config clip ! interface GigabitEthernet1/0/17 description SWITCH-1 FA0/1 switchport access vlan 101 switchport mode dot1q-tunnel duplex full speed 100 l2protocol-tunnel cdp l2protocol-tunnel stp l2protocol-tunnel vtp no cdp enable spanning-tree bpdufilter enable ! interface GigabitEthernet1/0/18 description SWITCH-2 FA0/1 switchport access vlan 201 switchport mode dot1q-tunnel duplex full speed 100 l2protocol-tunnel cdp l2protocol-tunnel stp l2protocol-tunnel vtp no cdp enable spanning-tree bpdufilter enable interface GigabitEthernet1/0/48 description SLIM (Ubuntu Server with 802.1q) switchport trunk encapsulation dot1q switchport mode trunk spanning-tree portfast end ############################################## Again, CDP is seen correctly on R1. R1 sees the downstream 3650 and not the 3750 in the middle. But the downstream 3650 does not see R1. It doesn't see anything. Everything else works great. No L3 issues whatsover. Well, except I won't be doing any ODR labs. :) THOUGHTS? --Hammer-- _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com
