IOS-XR_ASR9k_H-VPLS_with_MPLS_Access_Split_Horizon_Issue !

[Vaibhava Varma]

Dear All

I am working on a requirement to create a H-VPLS Setup with MPLS Access but am unable to get the setup working as the NPE is not able to send traffic received from other NPEs to the MPLS Access PW due to the Split-Horizon group being enabled by default for PW of same VFI.

After doing a lot of reading and digging am still unable to explore the option to disable split-horizon between the PWs of the same VFI. In IOS-XR I can not get anything equivalent to "neighbor 192.168.0.2 encapsulation mpls no-split-horizon" which I have configured at NPE3 to achieve communication between CE2 & CE4

Any pointers regarding this.Below is the setup for reference

                                    CE1----------AC-------------NPE1(ASR9k)

                                                                               !

                                                                               !

                                                                          xconnect

                                                                               !

                                                                               ! 

                                                                            VPLS           

                                                                               !           

                                                                               !

                                                                            NPE2(ASR9k)-----------------VPLS------------NPE3(IOS)--AC--CE3

                                                                                !                                                              !

                                                                                !                                                              !

                                                                              AC                                                            !                                                         

                                                                                !                                                              !

                                                                             CE2                                                           !             

                                                                                                                                  -         VPLS-----NPE4(IOS)---AC---CE4

NOTE:

1.CE2 can reach CE1,CE3,CE4

2.CE3 can reach CE2,CE4 but not CE1

3.CE4 can reach CE2,CE3 but not CE1

Regards

Vaibhava Varma

[xthuijs · Accepted solution]

yeah you cant disable split horizon in the vfi, it is the nature of the beast really.

IF you have HVPLS then your "access-pw's" need to be configured as if they are an AC, so outside the VFI.

You could, if you want to, move them to SHG2.

For more details on what SHG is where, you can check this message:

https://supportforums.cisco.com/message/3918240#3918240

regards

xander

[Vaibhava Varma]

Hi xander

I did come across that fact after some deep digging and the problem is now that my XR version does not supports access-pw under the bridge domain. I read more and found that H-VPLS is supported from XR 4.0 so now I will be upgrading the version.

Thanks for your insight into this issue.

Regards

Varma

[xthuijs]

Varma, aik yeah that is an old(er) release.

Access PW is configured like this and is available in all the "going" releases (xr423 or xr431 are the ones you probably

want to focus on)

RP/0/RSP0/CPU0:A9K-BNG(config)#l2vpn

RP/0/RSP0/CPU0:A9K-BNG(config-l2vpn)#bridge group test

RP/0/RSP0/CPU0:A9K-BNG(config-l2vpn-bg)#bridge-domain testing

RP/0/RSP0/CPU0:A9K-BNG(config-l2vpn-bg-bd)#neighbor ?

  A.B.C.D  IPv4 address of the peer

xander