l2vpn ping not working across the MPLS PE

[dgawaya1]

Dear experts, 
I have pw configured on the PEs and its up. However, the mpls pseudo ping is not working 

PE1

PE1#ping mpls pseudowire 192.168.239.18 5
Sending 5, 72-byte MPLS Echos to 192.168.239.18,
timeout is 2 seconds, send interval is 0 msec:

Codes: '!' - success, 'Q' - request not sent, '.' - timeout,
'L' - labeled output interface, 'B' - unlabeled output interface,
'D' - DS Map mismatch, 'F' - no FEC mapping, 'f' - FEC mismatch,
'M' - malformed request, 'm' - unsupported tlvs, 'N' - no label entry,
'P' - no rx intf label prot, 'p' - premature termination of LSP,
'R' - transit router, 'I' - unknown upstream index,
'l' - Label switched with FEC change, 'd' - see DDMAP for return code,
'X' - unknown return code, 'x' - return code 0

Type escape sequence to abort.
.....
Success rate is 0 percent (0/5)
Total Time Elapsed 9489 ms

interface GigabitEthernet1/0/1
description CE2
no ip address
negotiation auto
xconnect 192.168.239.18 5 encapsulation mpls

PE1#sh mpls l2transport vc 5

Local intf Local circuit Dest address VC ID Status
------------- -------------------------- --------------- ---------- ----------
Gi1/0/1 Ethernet 192.168.239.18 5 UP

.......
PE2

PE2#sh xconnect interface g0/0/2
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 Gi0/0/2:10(Ethernet) UP mpls 192.168.239.5:5 UP

interface GigabitEthernet0/0/2
description To CE1
no ip address
negotiation auto
xconnect 192.168.239.5 5 encapsulation mpls

///////////////In summary////

everything else is up. Please let me know if you need any other info. The PEs are Cisco ASR1k 

[MHM Cisco World]

pseudowire-class MHM

Encap mpls

Protocol ldp 

!

interface GigabitEthernet0/0/2
description To CE1
no ip address
negotiation auto
xconnect <ldp router-id> 5 encapsulation mpls pw-class MHM

This what I do for VPWS in ios xe' try do same and check.

Ldp router-id is important config correctly.

MHM

[dgawaya1]

Did this but did not work. I believe I have some issue in the underlay! There is not loop in the unicast but the mpls trace is strange. Please see attached  

[Harold Ritter]

Hi @dgawaya1 ,

You need to make sure that the MPLS LSP between the two PEs is functioning properly. You can do this with the following commands:

PE1:

ping mpls ipv4 192.168.239.18/32 source 192.168.239.5

PE2:

ping mpls ipv4 192.168.239.5/32 source 192.168.239.18

Regards,

[dgawaya1]

ping did not work. I did a trace and realised an issue in the traceroute 

[Harold Ritter]

Hi @dgawaya1 ,

The goal of the "ping mpls" was exactly to validate whether the LSP was not properly functioning end to end between the two PEs. The traceroute indicates that the issue is between the node that owns the 10.202.0.157 and the next hop towards 192.168.239.5. Make sure that LDP is properly configured and functioning between these two nodes. This should fix the issue and get your pseudowire working.

Regards,

[dgawaya1]

This may be some kind of bug. Look at the devices where the look is happening. The label assignment is complete on either side 

SYD1QAXDR001#show mpls ldp neighbor
Peer LDP Ident: 192.168.239.18:0; Local LDP Ident 192.168.239.31:0
TCP connection: 192.168.239.18.646 - 192.168.239.31.55632
State: Oper; Msgs sent/rcvd: 16840/16796; Downstream
Up time: 1w3d
LDP discovery sources:
Targeted Hello 192.168.239.31 -> 192.168.239.18, active, passive
GigabitEthernet0/0/1, Src IP addr: 10.202.0.158
Addresses bound to peer LDP Ident:
192.168.239.18 10.202.0.178 10.202.0.158
Peer LDP Ident: 192.168.239.17:0; Local LDP Ident 192.168.239.31:0
TCP connection: 192.168.239.17.646 - 192.168.239.31.28385
State: Oper; Msgs sent/rcvd: 12631/12635; Downstream
Up time: 1w0d
LDP discovery sources:
GigabitEthernet0/0/0, Src IP addr: 10.202.0.137
Targeted Hello 192.168.239.31 -> 192.168.239.17, active, passive
Addresses bound to peer LDP Ident:
192.168.239.17 10.202.0.137 10.202.0.177
.............

PER2QAXER001#show mpls ldp neighbor
Peer LDP Ident: 192.168.239.31:0; Local LDP Ident 192.168.239.18:0
TCP connection: 192.168.239.31.55632 - 192.168.239.18.646
State: Oper; Msgs sent/rcvd: 16811/16856; Downstream
Up time: 1w3d
LDP discovery sources:
Targeted Hello 192.168.239.18 -> 192.168.239.31, active, passive
GigabitEthernet0/0/0, Src IP addr: 10.202.0.157
Addresses bound to peer LDP Ident:
192.168.239.31 10.202.0.86 10.202.0.90 10.202.0.138
10.202.0.157

.........................

I wonder why 10.202.0.157 is showing No-Label !!! 
SYD1QAXDR001#sh ip int br | inc up
GigabitEthernet0/0/0 10.202.0.138 YES manual up up
GigabitEthernet0/0/1 10.202.0.157 YES manual up up
GigabitEthernet0/0/4 unassigned YES TFTP up up

[Harold Ritter]

Hi @dgawaya1 ,

According to the traceroute information you provided, the issue is not between PER2QAXER001 and SYD1QAXDR001, but rather SYD1QAXDR001 (who owns 10.202.0.157) and the node that is the next hop towards 192.168.239.5, as I mentioned previously.

 Do a "show ip cef 192.168.239.5" on SYD1QAXDR001 to find out which node is the next hop to 192.168.239.5 and check the LDP neighbor status between that node and SYD1QAXDR001. 

Regards,

[dgawaya1]

    SYD1QAXDR001 (10.202.0.157) <---> (10.202.0.158) PER2QAXER001.
You are right! For some reason SYD1QAXDR001 is not forming ldp adjacency with PER2QAXER001(192.168.239.18:lo0). That is breaking everything! 
Please see diagram attached 

SYD1QAXDR001#sh ip cef 192.168.239.5
192.168.239.5/32
nexthop 10.202.0.85 TenGigabitEthernet0/0/8
nexthop 10.202.0.89 TenGigabitEthernet0/1/8
SYD1QAXDR001#
SYD1QAXDR001#
SYD1QAXDR001#
SYD1QAXDR001#show mpls ldp ne
SYD1QAXDR001#show mpls ldp neighbor
Peer LDP Ident: 192.168.239.18:0; Local LDP Ident 192.168.239.31:0
TCP connection: 192.168.239.18.646 - 192.168.239.31.55632
State: Oper; Msgs sent/rcvd: 17040/16993; Downstream
Up time: 1w3d
LDP discovery sources:
Targeted Hello 192.168.239.31 -> 192.168.239.18, active, passive
GigabitEthernet0/0/1, Src IP addr: 10.202.0.158
Addresses bound to peer LDP Ident:
192.168.239.18 10.202.0.178 10.202.0.158
Peer LDP Ident: 192.168.239.17:0; Local LDP Ident 192.168.239.31:0
TCP connection: 192.168.239.17.646 - 192.168.239.31.28385
State: Oper; Msgs sent/rcvd: 12830/12836; Downstream
Up time: 1w0d
LDP discovery sources:
GigabitEthernet0/0/0, Src IP addr: 10.202.0.137
Targeted Hello 192.168.239.31 -> 192.168.239.17, active, passive
Addresses bound to peer LDP Ident:
192.168.239.17 10.202.0.137 10.202.0.177
SYD1QAXDR001#
SYD1QAXDR001#show mpls int
SYD1QAXDR001#show mpls interfaces
Interface IP Tunnel BGP Static Operational
GigabitEthernet0/0/0 Yes (ldp) No No No Yes
GigabitEthernet0/0/1 Yes (ldp) No No No Yes
Te0/0/8 Yes (ldp) No No No Yes
Te0/1/8 Yes (ldp) No No No Yes
SYD1QAXDR001#
SYD1QAXDR001#sh ip int br | inc up
GigabitEthernet0/0/0 10.202.0.138 YES manual up up
GigabitEthernet0/0/1 10.202.0.157 YES manual up up
GigabitEthernet0/0/4 unassigned YES TFTP up up
Te0/0/8 10.202.0.86 YES manual up up
Te0/1/8 10.202.0.90 YES manual up up
GigabitEthernet0 10.170.41.196 YES manual up up
Loopback0 192.168.239.31 YES manual up up
SYD1QAXDR001#
SYD1QAXDR001#
SYD1QAXDR001#

SYD1QAXDR001#show mpls forwarding-table 192.168.239.5
Local Outgoing Prefix Bytes Label Outgoing Next Hop
Label Label or Tunnel Id Switched interface
25 No Label 192.168.239.5/32 1889208 Te0/0/8 10.202.0.85
No Label 192.168.239.5/32 0 Te0/1/8 10.20

[Harold Ritter]

Hi @dgawaya1 ,

According to the "show mpls ldp neighbor" output you provided, SYD1QAXDR001 does have an LDP neighbor relationship to both PER1QAXER001 and PER2QAXER001, but it does not have an LDP neighbor relationship to SYD1QAXCR001 and SYD1QAXCR002. That is the reason the "show mpls forwarding-table 192.168.239.5" shows "no label" for both next hop for 192.168.239.5. This is the issue you need to fix.

Please check the LDP configuration on SYD1QAXCR001 and SYD1QAXCR002 on the interfaces towards SYD1QAXDR001. 

Regards,

[MHM Cisco World · Accepted solution]

there are two label in xconnect VPWS 
upper label between R1 to R2 
lower label between R1 to R3 (for VC)

each label need one neighboor 

upper label between R1 and R2 use UDP LDP 
lower label between R1 and R3 use TCP LDP (target ldp)

in your case if what you show is PE1 and PE2 I only see target UDP ?? i.e. you not run mpls ip under the interface connect PE1/PE2 to other router ??

Peer LDP Ident: 192.168.239.18:0; Local LDP Ident 192.168.239.31:0
TCP connection: 192.168.239.18.646 - 192.168.239.31.55632
State: Oper; Msgs sent/rcvd: 16840/16796; Downstream
Up time: 1w3d
LDP discovery sources:
Targeted Hello 192.168.239.31 -> 192.168.239.18, active, passive
GigabitEthernet0/0/1, Src IP addr: 10.202.0.158
Addresses bound to peer LDP Ident:
192.168.239.18 10.202.0.178 10.202.0.158
Peer LDP Ident: 192.168.239.17:0; Local LDP Ident 192.168.239.31:0
TCP connection: 192.168.239.17.646 - 192.168.239.31.28385
State: Oper; Msgs sent/rcvd: 12631/12635; Downstream
Up time: 1w0d
LDP discovery sources:
GigabitEthernet0/0/0, Src IP addr: 10.202.0.137
Targeted Hello 192.168.239.31 -> 192.168.239.17, active, passive
Addresses bound to peer LDP Ident:
192.168.239.17 10.202.0.137 10.202.0.177