ASR 9000 IOS-XR 5.22 BNG: PPPoE termination with PWHE

[GIANRICO FICHERA]

     I'm successfully using a classic BNG configuration for PPPoE clients using PW (xconnect).
Now I'm trying in lab the pseudowire headend configuration but without success.

Here is my configuration:

l2vpn
 pw-class gia1
  encapsulation mpls
   protocol ldp
   transport-mode ethernet
  !
 !
 xconnect group prova
  p2p numero1
   interface PW-Ether101
   neighbor ipv4 192.168.201.1 pw-id 888
   !
  !

interface PW-Ether101.1
 service-policy type control subscriber policy1
 pppoe enable bba-group bba1
 encapsulation dot1q 140
!

I receive the PPPoE client PADI and in the debug output you can see the PADO who inexplicably is not received from the client CPE:

RP/0/RSP0/CPU0:test_9001#RP/0/RSP0/CPU0:Feb 12 11:25:38.568 : pppoe_ma[453]: PW-Ether101.1: I dst ffff.ffff.ffff src 90f6.525a.ace1: len 46 0x11090000000c01010000010300040000016f00000000000000000000000000000000000000000000000000000000
RP/0/RSP0/CPU0:Feb 12 11:25:38.568 : pppoe_ma[453]: [PADI-Recv]: PW-Ether101.1 peer-mac 90f6.525a.ace1
RP/0/RSP0/CPU0:Feb 12 11:25:38.568 : pppoe_ma[453]: [PADI-Recv]:    vlan-id-outer 140
RP/0/RSP0/CPU0:Feb 12 11:25:38.568 : pppoe_ma[453]: [PADI-Recv]:    Service-name:
RP/0/RSP0/CPU0:Feb 12 11:25:38.568 : pppoe_ma[453]: [PADI-Recv]:    Host-uniq: 0000016f
RP/0/RSP0/CPU0:Feb 12 11:25:38.569 : pppoe_ma[453]: PW-Ether101.1: O dst 90f6.525a.ace1 src e0ac.f112.c675: len 31 0x11070000001901010000010300040000016f01020009746573745f39303031
RP/0/RSP0/CPU0:Feb 12 11:25:38.569 : pppoe_ma[453]: [PADO-Sent]: PW-Ether101.1 peer-mac 90f6.525a.ace1
RP/0/RSP0/CPU0:Feb 12 11:25:38.569 : pppoe_ma[453]: [PADO-Sent]:    vlan-id-outer 140

PADO packet disappears and there are zero packet in output in the pw-ether interface (and in the "show l2vpn xconnect detail" too)

RP/0/RSP0/CPU0:test_9001# sh int pw-ether 101.1
Thu Feb 12 11:31:02.071 UTC
PW-Ether101.1 is up, line protocol is up
  Interface state transitions: 11
  Hardware is VLAN sub-interface(s), address is e0ac.f112.c675
  Internet address is Unknown
  MTU 1518 bytes, BW 10000 Kbit (Max: 10000 Kbit)
     reliability 255/255, txload 0/255, rxload 0/255
  Encapsulation 802.1Q Virtual LAN, VLAN Id 140,  loopback not set,
  Last input 00:00:09, output never
  Last clearing of "show interface" counters never
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
     352 packets input, 22528 bytes, 0 total input drops
     0 drops for unrecognized upper-level protocol
     Received 352 broadcast packets, 0 multicast packets
     0 packets output, 0 bytes, 0 total output drops
     Output 0 broadcast packets, 0 multicast packets

show l2vpn xconnect detail

...

 Statistics:
      packets: received 672, sent 0
      bytes: received 43008, sent 0

...

Any ideas?

Thankyou 

Gianrico Fichera

ITESYS SRL

[andresfcl]

Hello,

In my case I was running 5.3.3 code and I cluld not even get any traffic under the xconenct when using the pseudowire head end function (pw-ether).

My config is simlar than the one psted by @GIANRICO, 

Same case using the regular xconnect it works but not when using the head end functionality.

[GIANRICO FICHERA]

Hi,

   there was a missing part in my configuration:

!
interface PW-Ether101
    attach generic-interface-list lista1 
!
generic-interface-list lista1                   
    interface GigabitEthernet0/0/0/2
!

I understood that is important what interfaces you put in the generic-interface-list.
There are two rules:
   - Until today you cannot use subinterfaces in the interface-list;
   - The interface list should be in the in the path to the user connecting;

Subinterfaces are not supported (at least up to version 6.1) and Cisco documentation says:

"PW TX traffic will only be sent to one of the paths in interface list  (based on VC-label hash) .Make sure the paths in the Interface-List are subset of the classic ECMP pathset chosen by IGPs for APE Loopback. If classic IGP pathset and IF-list set are disjoint PW TX traffic will be dropped."

So it could be the interface-list the cause of the zero TX traffic above.

Gianrico