L2TPv3 Requirement

Unanswered Question
Jul 20th, 2009
User Badges:

Helo Gurus,

Im moving forward to configure L2TPv3 on my GSR12000, 7206VXR and 7500, what are the requirements here? i read something that the 12000 series needs POS card to work? Do i need these?



  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 3 (1 ratings)
jeffersoncbriones Fri, 07/24/2009 - 17:30
User Badges:

Hi sbilqi,

I have this on my GSR12406, do i need a higher card for these, i get errors when configuring it. I tested this on 7206's and they work properly, but since i have GSR in between i have to make it work.

#sh diags 4

SLOT 4 (RP/LC 4 ): 4 Port Packet Over SONET OC-3c/STM-1 Single Mode

MAIN: type 33, 800-2389-02 rev M0

Deviation: 0

HW config: 0x00 SW key: FF-FF-FF

PCA: 73-2275-05 rev H0 ver 4

Design Release 1.1 S/N CAB0434BR3F

MBUS: MBUS Agent (1) 73-2146-07 rev B0 dev 0

HW version 1.2 S/N CAB0430B241

Test hist: 0xFF RMA#: FF-FF-FF RMA hist: 0xFF

DIAG: Test count: 0x00000000 Test results: 0x00000000

FRU: Linecard/Module: LC-4OC3/POS-SM=

Processor Memory: MEM-GRP/LC-256=

Packet Memory: MEM-LC-PKT-128=

L3 Engine: 0 - OC12 (622 Mbps)

MBUS Agent Software version 2.55 (RAM) (ROM version is 3.53)

ROM Monitor version 18.0

Fabric Downloader version used 26.1 (ROM version is 26.1)

Primary clock is CSC 1

Board is analyzed

Board State is Line Card Enabled (IOS RUN )

Insertion time: 23w2d (42w3d ago)

Processor Memory size: 268435456 bytes

TX Packet Memory size: 67108864 bytes

RX Packet Memory size: 67108864 bytes

0 crashes since restart


Giuseppe Larosa Sat, 07/25/2009 - 09:14
User Badges:
  • Super Silver, 17500 points or more
  • Hall of Fame,

    Founding Member

Hello Jeff,

>> but since i have GSR in between i have to make it work.

This is not a necessary step if GSR is just the node in the middle as I remember from the other thread in WAN forum you don't need to enable L2TPv3 on it:

the L2tpv3 has to be enabled on the two edge devices that have to implement the point-to-point L2 transport service over an IP tunnel.

Verify that you use loopbacks interfaces as L2tpv3 endpoint addresses and that those ip addresses are advertised in an IGP routing protocol like OSPF.

Be also aware that L2TPv3 is a point-to-point service like EoMPLS and so to interconnect three devices you need multiple L2TPv3 "tunnels".

Hope to help


jeffersoncbriones Sun, 07/26/2009 - 01:13
User Badges:

Hi Guieseppe,

You have been very helpful on your suggestions,I tried L2TPv on laboratory and gain me a lot of info and its working. The problem now is the last router is not possible to do the tunnel since its facing another provider.


So im left with link out of the GSR (facing the provider).EoMPLS i guess is the same concept as with L2TPv3? pls enlighten me on these.Im still starting to learn MPLS.



Giuseppe Larosa Fri, 07/31/2009 - 00:35
User Badges:
  • Super Silver, 17500 points or more
  • Hall of Fame,

    Founding Member

Hello Jeff,

sorry for late answer

yes EoMPLS is similar to L2TPv3 it provides a point-to-point L2 transport service.

The differences are the following:

LDP targeted sessions are used between endpoints instead of L2TPv3 messages

transported L2 frames are carried inside MPLS frames with a two labels stack: external label is the LSP towards loopback of other device

the more internal label exchanged on the targeted LDP session is the VC label and allows to identify the specific point-to-point service and the outgoing interface/subinterface and Vlan-id (if based on vlan subinterfaces EoMPLS allows for this level of granularity as L2TPv3 also does).

Hope to help


jeffersoncbriones Fri, 07/31/2009 - 00:45
User Badges:

Hi Guieseppe,

Thanks for the reply, i read about it also and a little bit the same L2TPv3. Im still reading a lot of MPLS info now and testing them.

Thanks for all the help.



This Discussion