cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
2325
Views
0
Helpful
4
Replies

Need help troubleshooting an L2TPv3 tunnel

spfister336
Level 2
Level 2

I've got a project I'm trying to use an l2tpv3 tunnel for. The tunnel seems to establish just fine, but it doesn't seem to do quite what I expected it to do. I'm trying to access vlans on a remote site that's connected via ATM. The remote side is connected by a 3640 router, plus a 8510 switch. On the local side, I've got another 3640, plus a 3500 switch.

As a possible clue, doing a 'show vlans' shows many packets output, but only a few input on the local side. On the remote side, the counts are zero in and out.

Here is a piece of the config on both sides. There is a vlan 77 on the network connected to f0/0 on the remote side that I'd like to be able to assign to the network connected to f0/0 on the local side.

Thanks!

--Steve

===========

remote side

===========

l2tp-class l2-dyn

hostname ABC

password <password>

cookie size 8

!

pseudowire-class pw-dynamic

encapsulation l2tpv3

protocol l2tpv3 l2-dyn

ip local interface FastEthernet0/0

!

interface FastEthernet0/0

ip address 10.77.0.1 255.255.0.0

no ip redirects

no ip proxy-arp

ip pim sparse-mode

ip route-cache flow

speed 100

full-duplex

!

interface FastEthernet0/0.77

encapsulation dot1Q 77

no snmp trap link-status

no cdp enable

xconnect 10.52.0.10 77 pw-class pw-dynamic

!

interface ATM1/0.2 multipoint

bandwidth 2284

ip address 10.99.60.77 255.255.255.0

ip pim sparse-mode

no ip mroute-cache

pvc data 0/277

protocol ip 10.99.60.1 broadcast

ubr 2284

broadcast

encapsulation aal5snap

!

!

==========

local side

==========

l2tp-class l2-dyn

hostname ADM

password <password>

cookie size 8

!

pseudowire-class pw-dynamic

encapsulation l2tpv3

protocol l2tpv3 l2-dyn

ip local interface FastEthernet0/0

!

interface FastEthernet0/0

no ip address

duplex auto

speed auto

!

interface FastEthernet0/0.77

encapsulation dot1Q 77

no snmp trap link-status

no cdp enable

xconnect 10.77.0.1 77 pw-class pw-dynamic

!

interface FastEthernet2/0

no ip address

no ip redirects

no ip proxy-arp

ip pim sparse-mode

duplex auto

speed auto

!

interface FastEthernet2/0.52

encapsulation dot1Q 52 native

ip address 10.52.0.10 255.255.0.0

no snmp trap link-status

!

4 Replies 4

merryllem
Level 1
Level 1

Hello,

Can you post the output of "show l2tun session all"

Giuseppe Larosa
Hall of Fame
Hall of Fame

Hello Steve,

first of all I would suggest you to move the L3 config to a subinterface instead of using the main physical interface at the remote site, just to be sure on the remote-site that different 802.1Q tags are used for frames of the vlan 77 and for frames of the routed vlan used as endpoint of the l2tvp3 trunk.

Have you got a trunk link to a switch port on the remote site ?

What is the native vlan on that trunk ?

If the native vlan is 77 on the switch side or the switch port is in access mode, you cannot see frames on vlan 77 on the router.

I would suggest to use loopback addresses as endpoints of the tunnel.

If the tunnel comes up but no traffic is flowing you may face a forwarding problem so leave the main interface not configured

hope to help

Giuseppe

hennigan
Level 1
Level 1

On the local side under the pseudowire you have:

ip local interface FastEthernet0/0

but your FastEthernet0/0 has no IP address.

I think you want the pseudowire to instead have an IP local of FastEthernet2/0.52

Better yet, tie the tunnel to loopback interfaces.

joealbergo
Level 1
Level 1

SP,

Whatever happened with this?

I don't see to much information about L2TPv3.

I am currently studying this ----

Hope to hear from you.

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community:

Innovations in Cisco Full Stack Observability - A new webinar from Cisco