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--
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