PWHE not passing traffic

[smeftahi]

I configured following setup:

PE: I match outer tag and POP it, then Xconnect to BNG.

BNG: PWHE is used for termination, at present no BNG dynamic profile is uses, just a simple subif.

Issue is, PWHE is up, but not sending any traffic, only receiving.

PE:

interface Bundle-Ether50.50 l2transport
encapsulation dot1q 50 second-dot1q any
rewrite ingress tag pop 1 symmetric
mtu 9000

BNG:

interface PW-Ether50
mtu 8996
mac-address 50.50.50
load-interval 30
attach generic-interface-list TEST_50
!

interface PW-Ether50.50
encapsulation ambiguous dot1q any second-dot1q 10

!

!!l2vpn config is same on both sides apart from remote loopback IPs:

pw-class PWHE
encapsulation mpls
transport-mode ethernet
!
!
xconnect group PWHE
p2p PWHE50
interface Bundle-Ether50.50
neighbor ipv4 192.168.1.2 pw-id 30150
pw-class PWHE

RP/0/RSP0/CPU0:lab1#sh l2vpn xconnect pw-id 30150 detail | i packets
Thu Jun 7 11:49:21.549 CETDST
packets: received 21, sent 0
packets: received 21, sent 0

Anyone tested similar setup or aware of limitations when tags are manipulated ?

Simple dot1q BEs work fine with PWHE.

TIA

/Sam

[xr-escalation]

hi Sam,

in principle, this config is pretty much standard for PWHE deployments and must work.

In your case, if you're popping one tag on PE, why do you still keep qinq encap on the PWHE sub-int side? If packets are going through the PW with a single dot1q tag, your PWHE sub-int should have a single dot1q tag.

/Aleksandar

[smeftahi]

Hi Aleksandar,

Good spot !

I am keeping Q-In-Q on PWHE because PE is actually receiving 3 tags :-)

Outer is popped, to allow me to do standard BNG termination.

Why 3 tags ? Wholesale scenario. 

/Sam

[xr-escalation]

hi Sam,

ok, so on BE50.50 frames come in with [50,any,10] tags and on PW-Ether50.50 they are received with [any,10]? In that case your config should work.

It seems the access PE is not sending anything into the PW (based on that show command snippet that you have shared). If you check the MAC address table on the PE, do you see the MAC 50.50.50?

best,
/Aleks

[smeftahi]

Thanks Aleks,

I am not sure if the stats are updating correctly.

Still not sent packets from BNG side PWHE, yet I am getting DHCP lease.

[xr-escalation]

hi Sam,

if you are getting DHCP offer from the server, it means the discovery was received, i.e. upstream direction works. Check the DHCP stats on the ingress (towards DHCP server) line card to confirm the offer was received. You can then run the "debug punt-inject l3-packets dhcpv4 ..." to confirm that the packet is further injected into the data-path. It may be a good idea to seek help from a TAC at this point.

/Aleks

[smeftahi]

Thanks Aleks,

After more testing, I was able to see traffic and actually validate that from a user perspective also.

Conclusion is, there is no cosmetic bug, and PWHE BNG is working as intended.

/Sam

[elesani]

can you share MPLS label allocation for the pw that is handling this? what's the outgoing interface (MPLS interface)?