XConnect between NCSs

[PavelKrasotin1244]

Hello

I have a question about configuring p2p l2vpn (pseudo-wire) betweein two NCS540.

Simpified schema is like this:

Simpified schema is like this:
Client_2(100.100.1.2/24)----vlan_98----TenGigE0/0/0/27.98_on_NCS1----MPLS/PW---NCS2_on_Bundle-Ether2.98----vlan_98-----Cleint1(100.100.1.1/24)

Configuration of l2vpn is symmetric on both routers:
NCS1:

interface TenGigE0/0/0/27.98 l2transport
 encapsulation dot1q 98 exact
!
l2vpn
 xconnect group XCON
  p2p 98
   interface TenGigE0/0/0/27.98
   neighbor ipv4 10.200.200.72 pw-id 98
    pw-class MPLS
!
l2vpn
 pw-class MPLS
  encapsulation mpls
   protocol ldp
!

NCS2:

interface Bundle-Ether2.98 l2transport
 encapsulation dot1q 98 exact
!
l2vpn
 xconnect group XCON
   p2p 98
    interface Bundle-Ether2.98
    neighbor ipv4 10.200.200.71 pw-id 98
     pw-class MPLS
!
l2vpn
 pw-class MPLS
  encapsulation mpls
   protocol ldp
!

PW is in UP state but the traffic (pings) doesn't go through it.

NCS540-1#sh l2vpn xconnect pw-id 98 detail
Wed Sep  8 17:16:27.674 MSK

Group XCONN, XC 98, state is up; Interworking none
  AC: TenGigE0/0/0/27.98, state is up
    Type VLAN; Num Ranges: 1
    Rewrite Tags: []
    VLAN ranges: [98, 98]
    MTU 9220; XC ID 0x18; interworking none
    Statistics:
      packets: received 0, sent 0
      bytes: received 0, sent 0
      drops: illegal VLAN 0, illegal length 0
  PW: neighbor 10.200.200.72, PW ID 98, state is up ( established )
    PW class MPLS, XC ID 0xc0000002
    Encapsulation MPLS, protocol LDP
    Source address 10.200.200.71
    PW type Ethernet, control word disabled, interworking none
    PW backup disable delay 0 sec
    Sequencing not set
    Ignore MTU mismatch: Disabled
    Transmit MTU zero: Disabled
    LSP : Up

    PW Status TLV in use
      MPLS         Local                          Remote                        
      ------------ ------------------------------ -----------------------------
      Label        24001                          24024                         
      Group ID     0x60                           0x8004014                     
      Interface    TenGigE0/0/0/27.98             Bundle-Ether2.98              
      MTU          9220                           9220                          
      Control word disabled                       disabled                      
      PW type      Ethernet                       Ethernet                      
      VCCV CV type 0x2                            0x2                           
                   (LSP ping verification)        (LSP ping verification)       
      VCCV CC type 0x6                            0x6                           
                   (router alert label)           (router alert label)          
                   (TTL expiry)                   (TTL expiry)                  
      ------------ ------------------------------ -----------------------------
    Incoming Status (PW Status TLV):
      Status code: 0x0 (Up) in Notification message
    Outgoing Status (PW Status TLV):
      Status code: 0x0 (Up) in Notification message
    MIB cpwVcIndex: 3221225474
    Create time: 07/09/2021 16:34:43 (1d00h ago)
    Last time status changed: 08/09/2021 17:16:23 (00:00:05 ago)
    Last time PW went down: 08/09/2021 16:11:17 (01:05:10 ago)
    Statistics:
      packets: received 0, sent 0
      bytes: received 0, sent 0

And If I reconfigure PW to bridge-domain all becоmes fine - clients can ping each other.

Have anyone an idea what can be wrong?

Thaks in advance!

[PavelKrasotin1244 · Accepted solution]

The problem was in bug - https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvv76274

Ethernet frames are not forwarded to psedo-wire if DST mac-address begins with 4.

The workaround is to add control-word to pw-class on bouth sides of pseudo-wire.