• Layer-2 VPN/VPWS (Virtual Private Wire Service) On Demand Next Hop (ODN) is not supported with peudowire (PW) class.

• The segment routing on demand for L2VPN or VPWS is not supported for BGP signaled/ADVPWS or Virtual Private LAN Service (VPLS).

• Only Segment-Routing TE tunnels are supported and created for L2VPN using attribute-set.

• L2VPN preferred path bandwidth related configuration does not take effect when TE attribute-set is configured.

• Only L2-VPN ODN VPWS with LDP signaling is supported.

On Demand Next Hop (ODN) for L2VPN creates an SR TE auto-tunnel and uses the auto-tunnel for pseudowire dataplane. The peer IP address is the destination of tunnel and TE LSP attribute determines path of the tunnel. Sometimes a pseudowire connection may need to span multiple interior gateway protocol (IGP) areas while LDP is used as signaling protocol. The pseudowire endpoint provider edge's (PE) loopback addresses are not distributed across IGP area boundaries. In this case, one PE may not have a default route (or an exact match route) in its RIB to reach the peer PE of the pseudowire connection. Thus the pseudowire connection can not be signaled by LDP. A new option autoroute destination is introduced under LSP attribute to address this problem. When a LSP attribute is configured using the autoroute destination command, auto-tunnel uses the LSP attribute to automatically create a static route for the tunnel destination with the auto-tunnel interface as the next hop. This static route enables LDP to establish a LDP a session and exchange label mapping messages between two pseudowire endpoints.

Note	Use the autoroute destination command only to configure LSP attribute used by LDP signaled L2VPN. It is not needed for BGP signaled Layer-3 VPN ODN.

You can use either pesudowire interface command or template method to configure L2VPN/VPWS.

To control the path of LSP it is possible to enable prepend option. The prepend option is only supported with intra-area and supports labeled paths only. To enable prepend option use the following CLI:

R1(config-lsp-attr)#path-selection segment-routing prepend 
R1(config-lsp-attr-sr-prepend)#?
Segment-routing label prepend commands:
  exit   Exist from segment-routing prepend config mode
  index  Specify the next entry index to add, edit or delete
  list   List all prepend entries
  no     Delete a specific entry index
R1(config-lsp-attr-sr-prepend)#index ?
  <1-10>  Entry index number
  last-hop    Indicates the end of label list
  next-label  Specify the next MPLS label in the path

Note	If last-hop option indicates tail end node. If this option is only used no control on LSP path can be done.

To bring down virtual circuit (VC) in case of LSP failure, which could be either because of path fail or removing a command, disable the fallback mode.

preferred-path segment-routing traffic-eng attribute-set L2VPNODN
disable-fallback  disable fall back to alternative route

For inter-area destination, IP address may not be installed at headend. You need to have destination IP address installed to enable a targeted LDP session for L2-VPN VPWS. To enable a targeted LDP session for L2VPN VPWS, configure the auto-route destination under the attribute set:

Device#
mpls traffic-eng lsp attributes L2VPNODN
 priority 7 7
 path-selection metric te
 pce
 autoroute destination
!
end

The destination address gets installed via L2-VPN ODN LSP as a static route.

Run the following commands to verify autoroute destination configuration:

Device#sh ip route 56.6.6.6
Routing entry for 56.6.6.6/32
  Known via "static", distance 1, metric 0 (connected)
  Routing Descriptor Blocks:
  * directly connected, via Tunnel2000------------------------ L2-VPN ODN LSP
      Route metric is 0, traffic share count is 1

Device#sh mpls for 56.6.6.6
Local      Outgoing             Prefix          Bytes Label      Outgoing   Next Hop    
Label      Label               or Tunnel Id     Switched          interface              
25           [T]  Pop Label    56.6.6.6/32      0                   Tu2000     point2point

1. sh mpls l2 vc

   
   Device#sh mpls l2 vc				
   Local intf     Local circuit              Dest address    VC ID      Status
   -------------  -------------------------- --------------- ---------- ----------
   Gi0/3/1        Eth VLAN 300               56.6.6.6        300        UP  
   

2. sh mpls l2 vc detail

   
   Device# sh mpls l2 vc detail
   Local interface: Gi0/3/1 up, line protocol up, Eth VLAN 300 up
     Interworking type is Ethernet
     Destination address: 56.6.6.6, VC ID: 300, VC status: up
       Output interface: Tu2000, imposed label stack {23 17 20}---- 20 is the VC label assigned by R6
       Preferred path: Tunnel2000,  active
       Default path: ready
       Next hop: point2point
     Create time: 00:15:48, last status change time: 00:15:38
       Last label FSM state change time: 00:15:38
     Signaling protocol: LDP, peer 56.6.6.6:0 up
       Targeted Hello: 51.1.1.1(LDP Id) -> 56.6.6.6, LDP is UP
       Graceful restart: not configured and not enabled
       Non stop routing: not configured and not enabled
       Status TLV support (local/remote)   : enabled/supported
         LDP route watch                   : enabled
         Label/status state machine        : established, LruRru
         Last local dataplane   status rcvd: No fault
         Last BFD dataplane     status rcvd: Not sent
         Last BFD peer monitor  status rcvd: No fault
         Last local AC  circuit status rcvd: No fault
         Last local AC  circuit status sent: No fault
         Last local PW i/f circ status rcvd: No fault
         Last local LDP TLV     status sent: No fault
         Last remote LDP TLV    status rcvd: No fault
         Last remote LDP ADJ    status rcvd: No fault
       MPLS VC labels: local 2032, remote 20 
       Group ID: local 20, remote 25
       MTU: local 1500, remote 1500
       Remote interface description: 
     Sequencing: receive disabled, send disabled
     Control Word: On (configured: autosense)
     SSO Descriptor: 56.6.6.6/300, local label: 2032
     Dataplane:
       SSM segment/switch IDs: 10198/6097 (used), PWID: 1001
     VC statistics:
       transit packet totals: receive 0, send 0
       transit byte totals:   receive 0, send 0
       transit packet drops:  receive 0, seq error 0, send 0
   
   

3. sh l2vpn atom preferred-path

   
   Device#  sh l2vpn atom preferred-path 
   Tunnel interface    Bandwidth Tot/Avail/Resv         Peer ID         VC ID
   -------------------       --------------------------------          ---------------     ----------
   Tunnel2000                                                              56.6.6.6        300       
   !
   end
   

4. sh l2vpn atom vc

   
   Device# sh l2vpn atom vc
   Interface Peer ID         VC ID      Type   Name                     Status
   --------- ---------------      ----------     ------ ------------------------ ----------
   pw4243    56.6.6.6        300        p2p    foobar                        UP  
   !
   end
   

5. sh mpl traffic-eng tun tun 2000

   
   Device# sh mpl traffic-eng tun tun 2000
   Name: R1_t2000                 (Tunnel2000) Destination: 56.6.6.6 Ifhandle: 0x7EE (auto-tunnel for atom)
     Status:
       Admin: up         Oper: up     Path: valid       Signalling: connected
       path option 1, (SEGMENT-ROUTING) (PCE) type dynamic (Basis for Setup, path weight 30)
     Config Parameters:
       Bandwidth: 0        kbps (Global)  Priority: 7  7   Affinity: 0x0/0xFFFF
       Metric Type: TE (interface)
       Path Selection:
        Protection: any (default)
       Path-selection Tiebreaker:
         Global: not set   Tunnel Specific: not set   Effective: min-fill (default)
       Hop Limit: disabled
       Cost Limit: disabled
       Path-invalidation timeout: 10000 msec (default), Action: Tear
       AutoRoute: disabled LockDown: disabled Loadshare: 0 [0] bw-based
       auto-bw: disabled
       Attribute-set: L2VPNODN
       Fault-OAM: disabled, Wrap-Protection: disabled, Wrap-Capable: No
     Active Path Option Parameters:
       State: dynamic path option 1 is active
       BandwidthOverride: disabled  LockDown: disabled  Verbatim: disabled
   PCEP Info:
       Delegation state: Working: yes   Protect: no
       Delegation peer: 58.8.8.8
       Working Path Info:
         Request status: processed
         Created via PCRep message from PCE server: 58.8.8.8
         PCE metric: 30, type: TE
       Reported paths:
         Tunnel Name: Tunnel2000_w
          LSPs:
           LSP[0]:
            source 51.1.1.1, destination 56.6.6.6, tunnel ID 2000, LSP ID 4
            State: Admin up, Operation active
            Binding SID: 20
            Setup type: SR
            Bandwidth: requested 0, used 0
            LSP object:
              PLSP-ID 0x807D0, flags: D:0 S:0 R:0 A:1 O:2
            Metric type: TE, Accumulated Metric 30
            ERO:
              SID[0]: Adj, Label 19, NAI: local 101.104.1.1 remote 101.104.1.2
              SID[1]: Adj, Label 23, NAI: local 103.104.12.2 remote 103.104.12.1
              SID[2]: Adj, Label 17, NAI: local 103.106.13.1 remote 103.106.13.2
          PLSP Event History (most recent first):
            Tue Jun 20 10:04:48.514: PCRpt create LSP-ID:4, SRP-ID:0, PST:1, METRIC_TYPE:2, REQ_BW:0, USED_BW:0
            Tue Jun 20 10:04:48.511: PCRep RP-ID:9
            Tue Jun 20 10:04:48.505: PCReq RP-ID:9, LSP-ID:4, REQ_BW:0
     History:
       Tunnel:
         Time since created: 18 minutes, 26 seconds
         Time since path change: 17 minutes, 9 seconds
         Number of LSP IDs (Tun_Instances) used: 4
       Current LSP: [ID: 4]
         Uptime: 17 minutes, 9 seconds
     Tun_Instance: 4
     Segment-Routing Path Info (isis  level-2)
       Segment0[Link]: 101.104.1.1 - 101.104.1.2, Label:  19-------- will not be shown in sh mpls l2 vc output
       Segment1[Link]: 103.104.12.2 - 103.104.12.1, Label: 23
       Segment2[Link]: 103.106.13.1 - 103.106.13.2, Label: 17
   !
   end
   
   

6. sh mpls ldp discovery

   
   Device# sh mpls ldp discovery
   Local LDP Identifier:
       51.1.1.1:0
       Discovery Sources:
       Targeted Hellos:
           51.1.1.1 -> 56.6.6.6 (ldp): active/passive, xmit/recv
               LDP Id: 56.6.6.6:0
   

7. sh mpl ldp nei

   
   Device# sh mpl ldp nei
   Peer LDP Ident: 56.6.6.6:0; Local LDP Ident 51.1.1.1:0
           TCP connection: 56.6.6.6.38574 - 51.1.1.1.646
           State: Oper; Msgs sent/rcvd: 43/42; Downstream
           Up time: 00:19:33
           LDP discovery sources:
             Targeted Hello 51.1.1.1 -> 56.6.6.6, active, passive
           Addresses bound to peer LDP Ident:
             105.106.2.2     103.106.13.2    56.6.6.6      
   !
   

8. sh int pseudowire 4243

   
   Device# sh int pseudowire 4243
   pseudowire4243 is up
       MTU 1500 bytes, BW not configured
       Encapsulation mpls
       Peer IP 56.6.6.6, VC ID 300
       RX    0 packets 0 bytes 0 drops
       TX    0 packets 0 bytes 0 drops
   !
   

9. sh xconnect all

   
   Device# sh xconnect all
   Legend:    XC ST=Xconnect State  S1=Segment1 State  S2=Segment2 State
     UP=Up       DN=Down            AD=Admin Down      IA=Inactive
     SB=Standby  HS=Hot Standby     RV=Recovering      NH=No Hardware
   
   XC ST  Segment 1                                    S1 Segment 2                         S2
   ------+---------------------------------+--+---------------------------------+--
   UP pri   ac Gi0/3/1:300(Eth VLAN)        UP mpls 56.6.6.6:300                 UP