[c-nsp] MPLS - Ping pseudowire only works in one direction

[Scott Harvanek]

I'm having a weird issue where I can ping a pseudowire in one direction, 
I'm starting to think this is just the nightmare that is MPLS on a 3750ME.

Topology:

Router-A                          Router-B
3750ME <--> MPLS/LDP network <--> 3750ME

VC Id is 1305

Router-A
Loopback: 10.0.2.1/32

Router-B
Loopback: 10.0.2.2/32

IP routing is good, no issues pinging each other from loopback and no 
issue performing a mpls ipv4 ping between 10.0.2.1 and 10.0.2.2.  VC is 
up and stable.

However when Router-A tries to ping the 1305 pseudowire, I get a 
timeout, when Router-B tries to ping it, success.  A packet capture 
seems to indicate that the ping request isn't even leaving Router-A..  
Has anyone seen it where a VC is fully up but pinging the pseudowire 
only works in one direction?

Local interface: Vl1305 up, line protocol up, Eth VLAN 1305 up
   Interworking type is Ethernet
   Destination address: 10.0.2.2, VC ID: 1305, VC status: up
     Output interface: Vl808, imposed label stack {65 21}
     Preferred path: not configured
     Default path: active
     Next hop: 10.0.2.34
   Create time: 08:44:37, last status change time: 00:04:49
   Signaling protocol: LDP, peer 10.0.2.2:0 up
     Targeted Hello: 10.0.2.1(LDP Id) -> 10.0.2.2
     Status TLV support (local/remote)   : enabled/not supported
       Label/status state machine        : established, LruRru
       Last local dataplane   status rcvd: no fault
       Last local SSS circuit status rcvd: no fault
       Last local SSS circuit status sent: no fault
       Last local  LDP TLV    status sent: no fault
       Last remote LDP TLV    status rcvd: not sent
     MPLS VC labels: local 22, remote 21
     Group ID: local 0, remote 0
     MTU: local 1998, remote 1998


ping mpls ipv4 10.0.2.2/32
Sending 5, 100-byte MPLS Echos to 10.0.2.2/32,
      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,
   'X' - unknown return code, 'x' - return code 0

Type escape sequence to abort.
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 67/67/67 ms


ping mpls pseudowire 10.0.2.2 1305
Sending 5, 100-byte MPLS Echos to 10.0.2.2,
      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,
   'X' - unknown return code, 'x' - return code 0

Type escape sequence to abort.
.....
Success rate is 0 percent (0/5)

Traffic also fails to pass in the direction of the failed pseudowire 
ping.  It works in the reverse where the ping works;

Router-B:
ping mpls pseudowire 10.0.2.1 1305
Sending 5, 100-byte MPLS Echos to 10.0.2.1,
      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,
   'X' - unknown return code, 'x' - return code 0

Type escape sequence to abort.
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 67/70/76 ms

-- 
Scott H.
Login Inc.