Unified-MPLS

[feroz syed]

Below topology having issue with end to end connectivity, Topology details follows

R1(CE) and R2 (PE) both connected via vrf vpnv4 bgp.

R2 (PE) R3 (PE) both connected to R4 (PC) using iBGP

R4(PC) & R5 (PC) also both using iBGP

R6 (PE)Connected to R7 (CE) device using vrf vpnv4 bgp.

R4 & R5 redistribute its loopback address to OSPF-1 Area0 (4.4.4.4 & 5.5.5.5)

Now the issue is R2  and R6 both can ping loopback address, but not able to ping opposite customer site.

Both Customer R1 and R7 have customer route but the trace not pass after R6 and R2.

[MHM Cisco World]

I would like both to work  in this LAB 
I will check config and update you

[feroz syed]

Thanks, sure, if you need i will share the gns config file.

[Harold Ritter · Accepted solution]

Hi @feroz syed ,

It is not sufficient to ping from R2 loopback to R6 loopback. You also need to validate that there is an end to end LSP between R2 and R6. You verify that using the following command:

ping mpls ipv4 6.6.6.6/32 source 2.2.2.2 

Regards,

[feroz syed]

hello mr.harold,

Thanks for the reply, you are right... seems there is label issue. i will trace the label and update this discussion.

R2#pin mpls ipv4 6.6.6.6/32 so 2.2.2.2
Sending 5, 100-byte MPLS Echos to 6.6.6.6/32,
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,
'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.
BBBBB
Success rate is 0 percent (0/5)
Total Time Elapsed 236 ms

--------------

R2#ping 6.6.6.6 so lo 0
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 6.6.6.6, timeout is 2 seconds:
Packet sent with a source address of 2.2.2.2
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/54/108 ms
R2#

[MHM Cisco World]

Sure this is MPLS Issue but how we can solve it, here the Q.
I will run lab hope tonight and update you. 

[feroz syed]

thank you for take time to diagnose the issue .

[Harold Ritter]

You can use the following command to pinpoint where the issue is:

traceroute mpls ipv4 6.6.6.6/32 source 2.2.2.2

Regards,

[feroz syed]

above cmd also shows the same result "BBBB"

from R4 i can see no lable for route 6.6.6.6/32

R4#sh mpls for
R4#sh mpls forwarding-table
Local Outgoing Prefix Bytes Label Outgoing Next Hop
Label Label or Tunnel Id Switched interface
400 Pop Label 5.5.5.5/32 0 Fa2/0 192.168.45.5
401 Pop Label 3.3.3.3/32 0 Fa1/0 192.168.34.3
402 Pop Label 2.2.2.2/32 0 Fa0/0 192.168.24.2
403 No Label 6.6.6.6/32 22995 Fa2/0 192.168.45.5

[Harold Ritter]

Hi @feroz syed ,

It looks like something went wrong with R4. Can you save the configuration, reload it and see if it makes a difference.

What is the IOS version you are currently running in your lab?

Regards,

[feroz syed]

send label cmd missing on R4

[feroz syed]

R1#ping 7.7.7.7 so lo 0
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 7.7.7.7, timeout is 2 seconds:
Packet sent with a source address of 1.1.1.1
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 188/244/324 ms
R1#

[feroz syed]

R4(config)#router bg 100
R4(config-router)#address
R4(config-router)#address-family ipv4
R4(config-router-af)#neigh 5.5.5.5 se
R4(config-router-af)#neigh 5.5.5.5 send-l
R4(config-router-af)#neigh 5.5.5.5 send-label
R4(config-router-af)#
*Sep 1 22:35:24.951: %BGP-5-ADJCHANGE: neighbor 5.5.5.5 Down Capability changed
*Sep 1 22:35:24.951: %BGP_SESSION-5-ADJCHANGE: neighbor 5.5.5.5 IPv4 Unicast topology base removed from session Capability changed
R4(config-router-af)#
*Sep 1 22:35:26.007: %BGP-5-ADJCHANGE: neighbor 5.5.5.5 Up
R4(config-router-af)#

[Harold Ritter]

Good catch @feroz syed . That should fix it.

Regards

[feroz syed]

why there is no cmd to see where the label is broken from end to end, instead of looking configs on routers.