My Network Lab: May 2019

MPLS LSP Ping

Because MPLS cannot work without IP on the network level, you can still use the IP ping when the network is running MPLS. The ping packets are labeled and label-switched throughout the network. Why invent MPLS LSP ping? Well, IP ping is insufficient for verifying the correctness of the MPLS LSP. Although it can verify whether the connectivity is present on the IP level, it does not verify whether the LSP is broken. If you have a plain IP-over-MPLS network and LDP is broken between two LSRs, ping indicates that there is no problem as the echo request makes it to the destination and the echo reply makes it back to the source. Between the two LSRs where the LDP session is broken, the packets are no longer labeled. The ping indicates falsely that everything is okay, when in reality the LSP is broken.

LSPs can break for any number of reasons, while the IP connectivity remains fine. Following are
some reasons an LSP could be broken:
* The LDP session is down.
* MPLS is not enabled on an LSR (or one interface).
* The LFIB has a wrong entry for that LSP (wrong in/out label or wrong outgoing next-hop
information).
* The software and hardware LFIB have a discrepancy.

MPLS LSP Traceroute

The goal of traceroute is to test the path, whereas the goal of ping is to test the connectivity. The goal of MPLS LSP traceroute is to test the path of the LSP and verify the control and data plane on every LSR along the path of the LSP.

An MPLS LSP traceroute is nothing more than an MPLS echo request. The difference with MPLS LSP ping is that MPLS LSP traceroute sends several MPLS echo request packets with increasing MPLS TTL. The first MPLS LSP traceroute probe has MPLS TTL 1, and for every subsequent probe, the TTL is increased by 1. One additional TLV that is included with the echo request for MPLS LSP traceroute is the Downstream Mapping TLV. If an LSR receives the MPLS echo request with TTL 1, it replies to it. If the LSR is not the egress LSR for the FEC and everything checks out fine, the LSR replies as one of the downstream routers. Therefore, it replies with a return code of 8 and the appropriate downstream TLV information (MTU, Address Type, Downstream IP Address, Downstream Interface Address, Multipath information, Downstream Label, and Protocol) filled in. If the LSR is the egress LSR for the FEC, it does not need to fill in the Downstream Mapping information but should reply with a return code of 3.

The MPLS echo request for an MPLS traceroute holds the following information:
* MPLS Echo Header
* Target FEC Stack TLV
* Downstream Mapping TLV
* A PAD TLV (optional)

The echo reply will hold the following information:
* MPLS Echo Header
* An Error Code TLV (optional)
* A PAD TLV (optional)
* Downstream Mapping TLV

R1-PE1#traceroute 10.5.5.5

Type escape sequence to abort.

Tracing the route to 10.5.5.5

VRF info: (vrf in name/id, vrf out name/id)

1 10.12.0.2 [MPLS: Label 202 Exp 0] 52 msec 48 msec 28 msec

2 10.23.0.3 [MPLS: Label 304 Exp 0] 32 msec 60 msec 36 msec

3 10.34.0.4 [MPLS: Label 402 Exp 0] 48 msec 8 msec 32 msec

4 10.45.0.5 64 msec 92 msec 48 msec

R3-P2#show mpls ldp ?

backoff LDP session setup backoff table

bindings Show the LDP Label Information Base (LIB)

capabilities Display LDP Capabilities information

discovery Display sources for locally generated LDP Discovery Hello

PDUs

graceful-restart Show Graceful Restart summary

igp IGP-related info

neighbor Display LDP neighbor information

parameters Display LDP configuration parameters

R3-P2#show mpls ldp bindings

lib entry: 10.1.1.1/32, rev 4

local binding: label: 301

remote binding: lsr: 10.4.4.4:0, label: 400

remote binding: lsr: 10.2.2.2:0, label: 200

lib entry: 10.2.2.2/32, rev 6

local binding: label: 302

remote binding: lsr: 10.4.4.4:0, label: 401

remote binding: lsr: 10.2.2.2:0, label: imp-null

lib entry: 10.3.3.3/32, rev 10

local binding: label: imp-null

remote binding: lsr: 10.4.4.4:0, label: 405

remote binding: lsr: 10.2.2.2:0, label: 205

lib entry: 10.4.4.4/32, rev 12

local binding: label: 303

remote binding: lsr: 10.4.4.4:0, label: imp-null

remote binding: lsr: 10.2.2.2:0, label: 201

lib entry: 10.5.5.5/32, rev 14

local binding: label: 304

remote binding: lsr: 10.4.4.4:0, label: 402

remote binding: lsr: 10.2.2.2:0, label: 202

lib entry: 10.12.0.0/24, rev 2

local binding: label: 300

remote binding: lsr: 10.4.4.4:0, label: 403

remote binding: lsr: 10.2.2.2:0, label: imp-null

lib entry: 10.23.0.0/24, rev 8

local binding: label: imp-null

remote binding: lsr: 10.4.4.4:0, label: 404

remote binding: lsr: 10.2.2.2:0, label: imp-null

lib entry: 10.34.0.0/24, rev 16

local binding: label: imp-null

remote binding: lsr: 10.4.4.4:0, label: imp-null

remote binding: lsr: 10.2.2.2:0, label: 203

lib entry: 10.45.0.0/24, rev 18

local binding: label: 305

remote binding: lsr: 10.4.4.4:0, label: imp-null

remote binding: lsr: 10.2.2.2:0, label: 204

R3-P2#show mpls ldp bindings ?

A.B.C.D Destination prefix

advertisement-acls Show advertisement access lists

all Display LIB information in all VRFs

detail Show detailed information

local Display only locally assigned labels

local-label Match locally assigned label values

neighbor Display labels from LDP neighbor

remote-label Match remotely assigned label values

vrf VRF Routing/Forwarding instance information

| Output modifiers

<cr>

R3-P2#show mpls ldp bindings local // PER PLATFORM LABEL; USE SAME LABELS IN OTHER INTERFACES

lib entry: 10.1.1.1/32, rev 4

local binding: label: 301

lib entry: 10.2.2.2/32, rev 6

local binding: label: 302

lib entry: 10.3.3.3/32, rev 10

local binding: label: imp-null // DIRECTLY CONNECTED

lib entry: 10.4.4.4/32, rev 12

local binding: label: 303

lib entry: 10.5.5.5/32, rev 14

local binding: label: 304

lib entry: 10.12.0.0/24, rev 2

local binding: label: 300

lib entry: 10.23.0.0/24, rev 8

local binding: label: imp-null

lib entry: 10.34.0.0/24, rev 16

local binding: label: imp-null

lib entry: 10.45.0.0/24, rev 18

local binding: label: 305

R3-P2#show mpls ldp bindings 10.5.5.5 32

lib entry: 10.5.5.5/32, rev 14

local binding: label: 304

remote binding: lsr: 10.4.4.4:0, label: 402 // TWO LABELS RECEIVED DUE TO LIBERAL LABEL RETENTION MODE

remote binding: lsr: 10.2.2.2:0, label: 202

R3-P2#conf t

Enter configuration commands, one per line. End with CNTL/Z.

R3-P2(config)#no mpls ip

R3-P2(config)#

*Nov 12 15:41:25.884: %LDP-5-NBRCHG: LDP Neighbor 10.4.4.4:0 (1) is DOWN (LDP unconfigured globally)

*Nov 12 15:41:25.888: %LDP-5-NBRCHG: LDP Neighbor 10.2.2.2:0 (2) is DOWN (LDP unconfigured globally)

R3-P2(config)#

R3-P2(config)#mpls ip

R3-P2(config)#

*Nov 12 15:41:33.612: %LDP-5-NBRCHG: LDP Neighbor 10.2.2.2:0 (3) is UP

*Nov 12 15:41:33.644: %LDP-5-NBRCHG: LDP Neighbor 10.4.4.4:0 (4) is UP

R3-P2#show mpls ldp bindings local

lib entry: 10.1.1.1/32, rev 2

local binding: label: 306

lib entry: 10.2.2.2/32, rev 4

local binding: label: 307

lib entry: 10.3.3.3/32, rev 6

local binding: label: imp-null

lib entry: 10.4.4.4/32, rev 8

local binding: label: 308

lib entry: 10.5.5.5/32, rev 10

local binding: label: 309

lib entry: 10.12.0.0/24, rev 12

local binding: label: 310

lib entry: 10.23.0.0/24, rev 14

local binding: label: imp-null

lib entry: 10.34.0.0/24, rev 16

local binding: label: imp-null

lib entry: 10.45.0.0/24, rev 18

local binding: label: 311

R3-P2#show mpls ldp bindings 10.5.5.5 32

lib entry: 10.5.5.5/32, rev 10

local binding: label: 309 // LABEL 304 PREVIOUSLY

remote binding: lsr: 10.2.2.2:0, label: 202 // NO CHANGE

remote binding: lsr: 10.4.4.4:0, label: 402 // NO CHANGE

R3-P2#show mpls forwarding-table 10.5.5.5

Local Outgoing Prefix Bytes Label Outgoing Next Hop

Label Label or Tunnel Id Switched interface

309 402 10.5.5.5/32 0 Fa1/0 10.34.0.4

R3-P2#conf t

Enter configuration commands, one per line. End with CNTL/Z.

R3-P2(config)#access-list 1 permit 10.5.5.5

R3-P2(config)#end

R3-P2#

*Nov 12 16:03:51.768: %SYS-5-CONFIG_I: Configured from console by console

R3-P2#debug mpls ?

access-list MPLS ACCESS

events MPLS events

ip Debug MPLS IP information

l2transport Any transport over MPLS debug

ldp Label Distribution Protocol

lspv LSP Verification debug

netflow MPLS Egress NetFlow Accounting

packet mpls packet debug

static MPLS Static labels

traffic-eng MPLS Traffic Engineering debug

R3-P2#debug mpls ldp ?

address-to-session Address to LDP session mapping services

advertisements LDP label and address advertisements

backoff LDP session establishment backoff

bindings Label bindings and other Label Information Base (LIB)

changes

capabilities Capabilities debug

dev MPLS development interested events

graceful-restart LDP Graceful Restart events

iccp InterChassis Control Protocol debug

igp IGP-related interactions

messages LDP messages

peer LDP peer

prev-label Previous label protocol changes

refcount LDP instance reference count tracking

session LDP session

targeted-neighbors LDP targeted neighbor events

transport LDP transport and discovery

R3-P2#debug mpls ldp bindings ?

peer-acl Peer access list filter

prefix-acl Prefix access list filter

<cr>

R3-P2#debug mpls ldp bindings prefix-acl ?

WORD ACL name

R3-P2#debug mpls ldp bindings prefix-acl 1 // LIMIT DEBUG BASED ON ACL 1 USING PREFIX 10.5.5.5

LDP Label Information Base (LIB) changes debugging is on for prefix ACL 1

R3-P2#

R3-P2#conf t

Enter configuration commands, one per line. End with CNTL/Z.

R3-P2(config)#no mpls ip

R3-P2(config)#

*Nov 12 16:04:32.496: %LDP-5-NBRCHG: LDP Neighbor 10.2.2.2:0 (3) is DOWN (LDP unconfigured globally)

*Nov 12 16:04:32.504: %LDP-5-NBRCHG: LDP Neighbor 10.4.4.4:0 (4) is DOWN (LDP unconfigured globally)

*Nov 12 16:04:32.708: tagcon: tibent(10.5.5.5/32): deleted

R3-P2(config)#

*Nov 12 16:04:34.100: tc_handle_bg_timer_event: TC not enabled, ctx # 0

*Nov 12 16:04:34.100: tagcon: (default) Deassign peer id; 10.2.2.2:0: id 2

*Nov 12 16:04:34.104: tagcon: (default) Deassign peer id; 10.4.4.4:0: id 3

R3-P2(config)#

R3-P2(config)#mpls ip

R3-P2(config)#

*Nov 12 16:04:43.892: tib: prefix recurs walk start: 10.5.5.5/32, tableid: 0; tib entry not found

*Nov 12 16:04:43.892: tib: get path labels: 10.5.5.5/32(0), nh tableid: 0, Fa1/0, nh 10.34.0.4

*Nov 12 16:04:43.892: tagcon: tibent(10.5.5.5/32): created; find route tags request

*Nov 12 16:04:43.892: tib: Assign 10.5.5.5/32 nh 10.34.0.4 real label

*Nov 12 16:04:43.896: tagcon: tibent(10.5.5.5/32): label 304 (#10) assigned

*Nov 12 16:04:43.896: tib: add a route info for 10.5.5.5/32(0, 10.34.0.4, Fa1/0), remote label Unknown

*Nov 12 16:04:43.896: tib: update route info for 10.5.5.5/32(0, 10.34.0.4, Fa1/0), with remote label Unknown

*Nov 12 16:04:43.896: tagcon: announce labels for: 10.5.5.5/32; nh 10.34.0.4, Fa1/0, inlabel 304, outlabel unknown (from 0.0.0.0:0), get path labels

*Nov 12 16:04:44.008: tib: prefix recurs walk start: 10.5.5.5/32, tableid: 0

*Nov 12 16:04:44.008: tib: get path labels: 10.5.5.5/32(0), nh tableid: 0, Fa1/0, nh 10.34.0.4

*Nov 12 16:04:44.012: tib: Assign 10.5.5.5/32 nh 10.34.0.4 real label

*Nov 12 16:04:44.012: tib: found route info for 10.5.5.5/32(0, 10.34.0.4, Fa1/0), remote label Unknown

*Nov 12 16:04:44.016: tib: update route info for 10.5.5.5/32(0, 10.34.0.4, Fa1/0), with remote label Unknown

*Nov 12 16:04:44.020: tagcon: announce labels for: 10.5.5.5/32; nh 10.34.0.4, Fa1/0, inlabel 304, outlabel unknown (from 0.0.0.0:0), get path labels

*Nov 12 16:04:44.100: tagcon: (default) Assign peer id; 10.2.2.2:0: id 0

*Nov 12 16:04:44.100: %LDP-5-NBRCHG: LDP Neighbor 10.2.2.2:0 (1) is UP

*Nov 12 16:04:44.156: tagcon: (default) Assign peer id; 10.4.4.4:0: id 1

*Nov 12 16:04:44.156: %LDP-5-NBRCHG: LDP Neighbor 10.4.4.4:0 (2) is UP

*Nov 12 16:04:44.156: tagcon: 10.4.4.4:0: 10.45.0.4 added to addr<->ldp ident map

*Nov 12 16:04:44.160: tagcon: 10.4.4.4:0: 10.34.0.4 added to addr<->ldp ident map

*Nov 12 16:04:44.160: tagcon: 10.4.4.4:0: 10.4.4.4 added to addr<->ldp ident map

*Nov 12 16:04:44.160: tib: 10.5.5.5/32:: learn binding 402 from 10.4.4.4:0

*Nov 12 16:04:44.164: tib: a new binding to be added

*Nov 12 16:04:44.164: tagcon: tibent(10.5.5.5/32): label 402 from 10.4.4.4:0 added

*Nov 12 16:04:44.164: tib: next hop for route 10.5.5.5/32(0, 10.34.0.4, Fa1/0) is mapped to peer 10.4.4.4:0

*Nov 12 16:04:44.164: tib: invoke iprm label announcement for 10.5.5.5/32

*Nov 12 16:04:44.164: tib: prefix recurs walk start: 10.5.5.5/32, tableid: 0

*Nov 12 16:04:44.164: tib: get path labels: 10.5.5.5/32(0), nh tableid: 0, Fa1/0, nh 10.34.0.4

*Nov 12 16:04:44.164: tib: Assign 10.5.5.5/32 nh 10.34.0.4 real label

*Nov 12 16:04:44.164: tib: found route info for 10.5.5.5/32(0, 10.34.0.4, Fa1/0), remote label Unknown

*Nov 12 16:04:44.164: tib: update route info for 10.5.5.5/32(0, 10.34.0.4, Fa1/0), with remote label 402 from 10.4.4.4:0

*Nov 12 16:04:44.164: tagcon: announce labels for: 10.5.5.5/32; nh 10.34.0.4, Fa1/0, inlabel 304, outlabel 402 (from 10.4.4.4:0), get path labels

*Nov 12 16:04:44.176: tagcon: 10.2.2.2:0: 10.12.0.2 added to addr<->ldp ident map

*Nov 12 16:04:44.176: tagcon: 10.2.2.2:0: 10.2.2.2 added to addr<->ldp ident map

*Nov 12 16:04:44.176: tagcon: 10.2.2.2:0: 10.23.0.2 added to addr<->ldp ident map

*Nov 12 16:04:44.180: tib: 10.5.5.5/32:: learn binding 202 from 10.2.2.2:0

*Nov 12 16:04:44.180: tib: a new binding to be added

*Nov 12 16:04:44.180: tagcon: tibent(10.5.5.5/32): label 202 from 10.2.2.2:0 added

*Nov 12 16:04:44.180: tib: next hop for route 10.5.5.5/32(0, 10.34.0.4, Fa1/0) is not mapped to peer 10.2.2.2:0

*Nov 12 16:04:44.180: tib: skip iprm label announcement for 10.5.5.5/32

R3-P2(config)#

R3-P2(config)#end

R3-P2#u all

All possible debugging has been turned off

R3-P2#show mpls ldp bindings 10.5.5.5 32

lib entry: 10.5.5.5/32, rev 10

local binding: label: 304

remote binding: lsr: 10.4.4.4:0, label: 402

remote binding: lsr: 10.2.2.2:0, label: 202

MPLS LDP Hello Message uses UDP Port 646 and it's sourced from the neighbor's interface IP address.

Expand User Datagram Protocol > click Source Port:646 > right-click > Prepare a Filter > Selected

In order to view the whole LDP session, type || tcp.port == 646 on the search filter (Expression) > press Enter.

MPLS LFIB exchange is established via TCP three-way handshake on port 646.

R3-P2#show mpls ldp neighbor

Peer LDP Ident: 10.2.2.2:0; Local LDP Ident 10.3.3.3:0

TCP connection: 10.2.2.2.646 - 10.3.3.3.47607 // R3 HAS THE HIGHER ROUTER ID (LOOPBACK IP) AND INITIATED THE TCP SESSION (3-WAY HANDSHAKE) USING HIGHER RANDOM (EPHEMERAL) SOURCE PORT GOING TO MPLS WELL KNOWN PORT 646

State: Oper; Msgs sent/rcvd: 37/36; Downstream

Up time: 00:21:56

LDP discovery sources:

FastEthernet1/1, Src IP addr: 10.23.0.2

Addresses bound to peer LDP Ident:

10.12.0.2 10.2.2.2 10.23.0.2 // LDP NEIGHBOR ALSO ADVERTISE ITS KNOWN NETWORKS

Peer LDP Ident: 10.4.4.4:0; Local LDP Ident 10.3.3.3:0

TCP connection: 10.4.4.4.57765 - 10.3.3.3.646

State: Oper; Msgs sent/rcvd: 37/37; Downstream

Up time: 00:21:56

LDP discovery sources:

FastEthernet1/0, Src IP addr: 10.34.0.4

Addresses bound to peer LDP Ident:

10.45.0.4 10.34.0.4 10.4.4.4

R5-PE2#show control-plane host open-ports // VERIFY OPENED PORTS FOBGP AND MPLS PING/TRACEROUTE

Active internet connections (servers and established)

Prot Local Address Foreign Address Service State

tcp *:51815 192.168.1.2:179 IOS host service ESTABLIS

tcp *:23 *:0 Telnet LISTEN

tcp *:31529 10.4.4.4:646 IOS host service ESTABLIS

tcp *:30089 10.1.1.1:179 IOS host service ESTABLIS

tcp *:179 *:0 BGP LISTEN

udp *:3503 *:0 LSPV Echo LISTEN

R3-P2#show ip route

Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP

+ - replicated route, % - next hop override

Gateway of last resort is not set

10.0.0.0/8 is variably subnetted, 11 subnets, 2 masks

O 10.1.1.1/32 [110/3] via 10.23.0.2, 1d04h, FastEthernet1/1

O 10.2.2.2/32 [110/2] via 10.23.0.2, 1d04h, FastEthernet1/1

C 10.3.3.3/32 is directly connected, Loopback0

O 10.4.4.4/32 [110/2] via 10.34.0.4, 1d04h, FastEthernet1/0

O 10.5.5.5/32 [110/3] via 10.34.0.4, 1d04h, FastEthernet1/0

O 10.12.0.0/24 [110/2] via 10.23.0.2, 1d04h, FastEthernet1/1

C 10.23.0.0/24 is directly connected, FastEthernet1/1

L 10.23.0.3/32 is directly connected, FastEthernet1/1

C 10.34.0.0/24 is directly connected, FastEthernet1/0

L 10.34.0.3/32 is directly connected, FastEthernet1/0

O 10.45.0.0/24 [110/2] via 10.34.0.4, 1d04h, FastEthernet1/0

R3-P2#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

R3-P2(config)#ip route 10.2.2.2 255.255.255.255 10.34.0.4 // WRONG STATIC ROUTE

R3-P2(config)#

R3-P2(config)#no mpls ip

R3-P2(config)#

*Nov 12 16:49:13.188: %LDP-5-NBRCHG: LDP Neighbor 10.2.2.2:0 (3) is DOWN (LDP unconfigured globally)

*Nov 12 16:49:13.196: %LDP-5-NBRCHG: LDP Neighbor 10.4.4.4:0 (4) is DOWN (LDP unconfigured globally)

R3-P2(config)#

*Nov 12 16:49:13.356: %MPLS_PACKET-4-NOLFDSB: MPLS packet received on non MPLS enabled interface FastEthernet1/0 L3 type 0x8847 label {303 6 1 254}

R3-P2(config)#

R3-P2(config)#mpls ip

R3-P2(config)#

*Nov 12 16:49:23.056: %LDP-5-NBRCHG: LDP Neighbor 10.4.4.4:0 (1) is UP // LDP NEIGHBOR R2 DIDN'T GO UP; IT CAN'T REACH R2 LOOPBACK IP 10.2.2.2

R3-P2(config)#

R3-P2(config)#do show mpls ldp neighbor

Peer LDP Ident: 10.4.4.4:0; Local LDP Ident 10.3.3.3:0

TCP connection: 10.4.4.4.14003 - 10.3.3.3.646

State: Oper; Msgs sent/rcvd: 12/12; Downstream

Up time: 00:00:13

LDP discovery sources:

FastEthernet1/0, Src IP addr: 10.34.0.4

Addresses bound to peer LDP Ident:

10.45.0.4 10.34.0.4 10.4.4.4

R3-P2(config)#

R3-P2(config)#no ip route 10.2.2.2 255.255.255.255 10.34.0.4 // RESTORE ROUTING FOR 10.2.2.2 DYNAMICALLY VIA OSPF

R3-P2(config)#

*Nov 12 16:50:11.792: %LDP-5-NBRCHG: LDP Neighbor 10.2.2.2:0 (2) is UP

R3-P2(config)#

R3-P2(config)#do show mpls ldp neighbor // MPLS ESTABLISH LDP NEIGHBORSHIP USING HIGHEST LOOPBACK IP

Peer LDP Ident: 10.4.4.4:0; Local LDP Ident 10.3.3.3:0

TCP connection: 10.4.4.4.14003 - 10.3.3.3.646

State: Oper; Msgs sent/rcvd: 13/13; Downstream

Up time: 00:01:00

LDP discovery sources:

FastEthernet1/0, Src IP addr: 10.34.0.4

Addresses bound to peer LDP Ident:

10.45.0.4 10.34.0.4 10.4.4.4

Peer LDP Ident: 10.2.2.2:0; Local LDP Ident 10.3.3.3:0

TCP connection: 10.2.2.2.646 - 10.3.3.3.24330

State: Oper; Msgs sent/rcvd: 12/12; Downstream

Up time: 00:00:11

LDP discovery sources:

FastEthernet1/1, Src IP addr: 10.23.0.2

Addresses bound to peer LDP Ident:

10.12.0.2 10.2.2.2 10.23.0.2

Verify CUSTA SITE 1 has network connectivity to 192.168.1.99 in CUSTA SITE 2. Troubleshoot backwards on the LSP: CUSTA-SITE2 > R5-PE2 > R4-P3 > R3-P2 > R2-P1 > R1-PE1 > CUSTA-SITE1.

CUSTA-SITE2#show ip interface brief

Interface IP-Address OK? Method Status Protocol

FastEthernet0/0 unassigned YES unset administratively down down

FastEthernet1/0 192.168.1.2 YES manual up up

FastEthernet1/1 unassigned YES unset administratively down down

Loopback1 192.168.1.99 YES manual up up

R5-PE2#show bgp vpnv4 unicast vrf CUSTA label

Network Next Hop In label/Out label

Route Distinguisher: 65000:1 (CUSTA)

172.16.1.0/30 10.1.1.1 nolabel/107

172.16.1.99/32 10.1.1.1 nolabel/108

192.168.1.0/30 0.0.0.0 509/nolabel(CUSTA)

192.168.1.99/32 192.168.1.2 510/nolabel

R5-PE2#show bgp vpnv4 unicast vrf CUSTA 192.168.1.99

BGP routing table entry for 65000:1:192.168.1.99/32, version 13

Paths: (1 available, best #1, table CUSTA)

Advertised to update-groups:

Refresh Epoch 1

Local

192.168.1.2 from 0.0.0.0 (10.5.5.5)

Origin incomplete, metric 1, localpref 100, weight 32768, valid, sourced, best

Extended Community: RT:1:1

mpls labels in/out 510/nolabel

R5-PE2#show mpls forwarding-table vrf CUSTA 192.168.1.99

Local Outgoing Prefix Bytes Label Outgoing Next Hop

Label Label or Tunnel Id Switched interface

510 No Label 192.168.1.99/32[V] \

2370 Fa1/0 192.168.1.2

R5-PE2#show ip cef vrf CUSTA 192.168.1.99

192.168.1.99/32

nexthop 192.168.1.2 FastEthernet1/0

R1-PE1#show bgp vpnv4 unicast vrf CUSTA label

Network Next Hop In label/Out label

Route Distinguisher: 65000:1 (CUSTA)

172.16.1.0/30 0.0.0.0 107/nolabel(CUSTA)

172.16.1.99/32 172.16.1.2 108/nolabel

192.168.1.0/30 10.5.5.5 nolabel/509

192.168.1.99/32 10.5.5.5 nolabel/510

R1-PE1#show mpls forwarding-table 10.5.5.5

Local Outgoing Prefix Bytes Label Outgoing Next Hop

Label Label or Tunnel Id Switched interface

106 205 10.5.5.5/32 0 Fa0/0 10.12.0.2

R1-PE1#show ip cef vrf CUSTA 192.168.1.99

192.168.1.99/32

nexthop 10.12.0.2 FastEthernet0/0 label 205 510 // TOP LABEL: 209; BOTTOM LABEL: 510

CUSTA-SITE2#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

CUSTA-SITE2(config)#line vty 0 4 // ENABLE TELNET FOR TESTING

CUSTA-SITE2(config-line)#no login

CUSTA-SITE2(config-line)#privilege 15

CUSTA-SITE2(config-line)#privilege level 15

CUSTA-SITE2(config-line)#end

CUSTA-SITE2#

CUSTA-SITE1#show ip route

Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP

+ - replicated route, % - next hop override

Gateway of last resort is not set

172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks

C 172.16.1.0/30 is directly connected, FastEthernet1/0

L 172.16.1.2/32 is directly connected, FastEthernet1/0

C 172.16.1.99/32 is directly connected, Loopback1

192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks

O E2 192.168.1.0/30 [110/1] via 172.16.1.1, 1d16h, FastEthernet1/0

O E2 192.168.1.99/32 [110/1] via 172.16.1.1, 1d16h, FastEthernet1/0

CUSTA-SITE1#traceroute 192.168.1.99

Type escape sequence to abort.

Tracing the route to 192.168.1.99

VRF info: (vrf in name/id, vrf out name/id)

1 172.16.1.1 16 msec 20 msec 16 msec // R1-PE1

2 10.12.0.2 [MPLS: Labels 205/510 Exp 0] 108 msec 72 msec 92 msec // R2-P1

3 10.23.0.3 [MPLS: Labels 309/510 Exp 0] 128 msec 72 msec 72 msec // R3-P2

4 10.34.0.4 [MPLS: Labels 405/510 Exp 0] 84 msec 72 msec 88 msec // R4-P3 (PHP)

5 192.168.1.1 [MPLS: Label 510 Exp 0] 72 msec 40 msec 64 msec // R5-PE2; BOTTOM LABEL:510

6 192.168.1.2 96 msec 80 msec 68 msec // CUSTA-SITE2; NATIVE IP

CUSTA-SITE1#telnet 192.168.1.99

Trying 192.168.1.99 ... Open

CUSTA-SITE2#

Perform Wireshark packet capture between R2-P1 and R3-P2. Notice the Ethernet II (Layer 2/Data Link) has a Type: MPLS label switched packet (MPLS is Layer 2.5). Also the MPLS Label: 310 has a Bottom of Label Stack: 1

CUSTA-SITE1#ping 192.168.1.99

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 192.168.1.99, timeout is 2 seconds:

!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 72/90/104 ms

The ICMP reply packet is the reverse Label Switch Path (LSP) from CUSTA-SITE2 (192.168.1.99) to CUSTA-SITE1 (172.16.1.2).

There's a slight difference with the commands used in configuring and troubleshooting a VRF.

Configure the CE routers to allow Telnet for testing purposes.

CUSTA-SITE1#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
CUSTA-SITE1(config)#line vty 0 4
CUSTA-SITE1(config-line)#no login
CUSTA-SITE1(config-line)#privilege level 15
CUSTA-SITE1(config-line)#end
CUSTA-SITE1#

CUSTB-SITE1#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
CUSTB-SITE1(config)#line vty 0 4
CUSTB-SITE1(config-line)#no login
CUSTB-SITE1(config-line)#privilege level 15
CUSTB-SITE1(config-line)#end
CUSTB-SITE1#

CUSTB-SITE2#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
CUSTB-SITE2(config)#line vty 0 4
CUSTB-SITE2(config-line)#no login
CUSTB-SITE2(config-line)#privilege level 15
CUSTB-SITE2(config-line)#end
CUSTB-SITE2#

R1-PE1#ping 172.16.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.2, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)

R1-PE1#ping 172.16.1.2 // PING FAILED SINCE IP IS NOT IN GLOBAL ROUTING TABLE

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 172.16.1.2, timeout is 2 seconds:

.....

Success rate is 0 percent (0/5)

R1-PE1#show ip route

Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP

+ - replicated route, % - next hop override

Gateway of last resort is not set

10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks

C 10.1.1.1/32 is directly connected, Loopback0

O 10.2.2.2/32 [110/2] via 10.12.0.2, 1w3d, FastEthernet0/0

O 10.3.3.3/32 [110/3] via 10.12.0.2, 1w3d, FastEthernet0/0

O 10.4.4.4/32 [110/4] via 10.12.0.2, 1w3d, FastEthernet0/0

O 10.5.5.5/32 [110/5] via 10.12.0.2, 1w3d, FastEthernet0/0

C 10.12.0.0/24 is directly connected, FastEthernet0/0

L 10.12.0.1/32 is directly connected, FastEthernet0/0

O 10.23.0.0/24 [110/2] via 10.12.0.2, 1w3d, FastEthernet0/0

O 10.34.0.0/24 [110/3] via 10.12.0.2, 1w3d, FastEthernet0/0

O 10.45.0.0/24 [110/4] via 10.12.0.2, 1w3d, FastEthernet0/0

R1-PE1#show ip route ?

Hostname or A.B.C.D Network to display information about or hostname

bgp Border Gateway Protocol (BGP)

connected Connected

dhcp Show routes added by DHCP Server or Relay

eigrp Enhanced Interior Gateway Routing Protocol (EIGRP)

isis ISO IS-IS

lisp Locator ID Separation Protocol (LISP)

list IP Access list

loops RIB routes forming loops

mobile Mobile routes

multicast Multicast global information

next-hop-override Show next-hop-overrides too

nhrp Next Hop Resolution Protocol (NHRP)

odr On Demand stub Routes

ospf Open Shortest Path First (OSPF)

ospfv3 OSPFv3

profile IP routing table profile

repair-paths Show repair paths too

rip Routing Information Protocol (RIP)

static Static routes

summary Summary of all routes

supernets-only Show supernet entries only

tag Route Tag

track-table Tracked static table

vrf Display routes from a VPN Routing/Forwarding instance

| Output modifiers

<cr>

R1-PE1#show ip route vrf CUSTA

Routing Table: CUSTA

Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP

+ - replicated route, % - next hop override

Gateway of last resort is not set

172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks

C 172.16.1.0/30 is directly connected, FastEthernet1/0

L 172.16.1.1/32 is directly connected, FastEthernet1/0

O 172.16.1.99/32 [110/2] via 172.16.1.2, 2d19h, FastEthernet1/0

192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks

B 192.168.1.0/30 [200/0] via 10.5.5.5, 2d13h

B 192.168.1.99/32 [200/1] via 10.5.5.5, 2d13h

R1-PE1#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

R1-PE1(config)#ip route ?

A.B.C.D Destination prefix

profile Enable IP routing table profile

static Allow static routes

vrf Configure static route for a VPN Routing/Forwarding instance

R1-PE1(config)#ip route vrf CUSTA 10.1.1.0 255.255.255.0 172.16.1.2

R1-PE1(config)#end

R1-PE1#show ip route vrf CUSTA

Routing Table: CUSTA

Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP

+ - replicated route, % - next hop override

Gateway of last resort is not set

10.0.0.0/24 is subnetted, 1 subnets

S 10.1.1.0 [1/0] via 172.16.1.2

172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks

C 172.16.1.0/30 is directly connected, FastEthernet1/0

L 172.16.1.1/32 is directly connected, FastEthernet1/0

O 172.16.1.99/32 [110/2] via 172.16.1.2, 2d19h, FastEthernet1/0

192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks

B 192.168.1.0/30 [200/0] via 10.5.5.5, 2d13h

B 192.168.1.99/32 [200/1] via 10.5.5.5, 2d13h

R1-PE1#show ip route vrf CUSTB

Routing Table: CUSTB

Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP

+ - replicated route, % - next hop override

Gateway of last resort is not set

172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks

C 172.16.1.0/30 is directly connected, FastEthernet1/1

L 172.16.1.1/32 is directly connected, FastEthernet1/1

D 172.16.1.100/32 [90/156160] via 172.16.1.2, 2d19h, FastEthernet1/1

192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks

B 192.168.1.0/30 [200/0] via 10.5.5.5, 2d19h

B 192.168.1.100/32 [200/0] via 10.5.5.5, 2d19h

R1-PE1#ping vrf CUSTA 172.16.1.2 // CUSTA-SITE1

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 172.16.1.2, timeout is 2 seconds:

!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 8/16/24 ms

R1-PE1#ping vrf CUSTB 172.16.1.2 // CUSTB-SITE1

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 172.16.1.2, timeout is 2 seconds:

!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 8/12/24 ms

R1-PE1#ping vrf CUSTA 192.168.1.2 // CUSTA-SITE2

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 192.168.1.2, timeout is 2 seconds:

!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 72/91/132 ms

R1-PE1#ping vrf CUSTB 192.168.1.2 // CUSTB-SITE2

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 192.168.1.2, timeout is 2 seconds:

!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 44/64/84 ms

R1-PE1#traceroute ?

WORD Trace route to destination address or hostname

appletalk AppleTalk Trace

clns ISO CLNS Trace

ethernet Ethernet Traceroute

ip IP Trace

ipv6 IPv6 Trace

ipx IPX Trace

mpls MPLS LSP Trace

vrf Select VPN routing instance

<cr>

R1-PE1#traceroute vrf CUSTA 172.16.1.99 // MPLS TRACEROUTE USES HIGH NUMBERED UDP PORTS

Type escape sequence to abort.

Tracing the route to 172.16.1.99

VRF info: (vrf in name/id, vrf out name/id)

1 172.16.1.2 20 msec 12 msec 12 msec // DIRECTLY CONNECTED (NO MPLS)

R1-PE1#traceroute vrf CUSTA 192.168.1.2

Type escape sequence to abort.

Tracing the route to 192.168.1.2

VRF info: (vrf in name/id, vrf out name/id)

1 10.12.0.2 [MPLS: Labels 205/509 Exp 0] 44 msec 56 msec 44 msec // SAME DESTINATION IP BUT DIFFERENT EGRESS MPLS LABEL; Exp IS THE EXPERIMENTAL BITS USED FOR QoS

2 10.23.0.3 [MPLS: Labels 309/509 Exp 0] 64 msec 44 msec 40 msec

3 10.34.0.4 [MPLS: Labels 405/509 Exp 0] 48 msec 56 msec 44 msec

4 192.168.1.1 52 msec 36 msec 52 msec

5 192.168.1.2 84 msec 48 msec 56 msec

R1-PE1#traceroute vrf CUSTB 192.168.1.2

Type escape sequence to abort.

Tracing the route to 192.168.1.2

VRF info: (vrf in name/id, vrf out name/id)

1 10.12.0.2 [MPLS: Labels 205/507 Exp 0] 40 msec 60 msec 60 msec

2 10.23.0.3 [MPLS: Labels 309/507 Exp 0] 48 msec 40 msec 44 msec

3 10.34.0.4 [MPLS: Labels 405/507 Exp 0] 40 msec 52 msec 48 msec

4 192.168.1.1 40 msec 48 msec 60 msec

5 192.168.1.2 64 msec 72 msec 60 msec

R1-PE1#telnet 192.168.1.2 ?

/debug Enable telnet debugging mode

/encrypt Negotiate telnet encryption

/ipv4 Force use of IP version 4

/ipv6 Force use of IP version 6

/line Enable telnet line mode

/noecho Disable local echo

/quiet Suppress login/logout messages

/route: Enable telnet source route mode

/source-interface Specify source interface

/stream Enable stream processing

/terminal-type Set terminal type

/vrf Select VPN routing/forwarding instance

<0-65535> Port number

bgp Border Gateway Protocol (179)

chargen Character generator (19)

cmd Remote commands (rcmd, 514)

daytime Daytime (13)

discard Discard (9)

domain Domain Name Service (53)

drip Dynamic Routing Information Protocol (3949)

echo Echo (7)

exec Exec (rsh, 512)

finger Finger (79)

ftp File Transfer Protocol (21)

ftp-data FTP data connections (20)

gopher Gopher (70)

hostname NIC hostname server (101)

ident Ident Protocol (113)

irc Internet Relay Chat (194)

klogin Kerberos login (543)

kshell Kerberos shell (544)

lpd Printer service (515)

nntp Network News Transport Protocol (119)

pim-auto-rp PIM Auto-RP (496)

pop2 Post Office Protocol v2 (109)

pop3 Post Office Protocol v3 (110)

smtp Simple Mail Transport Protocol (25)

sunrpc Sun Remote Procedure Call (111)

tacacs TAC Access Control System (49)

talk Talk (517)

telnet Telnet (23)

time Time (37)

uucp Unix-to-Unix Copy Program (540)

whois Nicname (43)

www World Wide Web (HTTP, 80)

<cr>

R1-PE1#telnet 192.168.1.2 /vrf ?

WORD VPN Routing/forwarding instance name

R1-PE1#telnet 192.168.1.2 /vrf CUSTA

Trying 192.168.1.2 ... Open

CUSTA-SITE2#

R1-PE1#telnet 192.168.1.2 /vrf CUSTB

Trying 192.168.1.2 ... Open

CUSTB-SITE2#

CUSTA-SITE1#traceroute 192.168.1.99

Type escape sequence to abort.

Tracing the route to 192.168.1.99

VRF info: (vrf in name/id, vrf out name/id)

1 172.16.1.1 48 msec 44 msec 16 msec

2 10.12.0.2 [MPLS: Labels 205/510 Exp 0] 88 msec 72 msec 76 msec // YOU CAN OPTIONALLY HIDE THE MPLS LABEL AND TTL IN A TRACEROUTE OUTPUT

3 10.23.0.3 [MPLS: Labels 309/510 Exp 0] 72 msec 76 msec 48 msec

4 10.34.0.4 [MPLS: Labels 405/510 Exp 0] 72 msec 72 msec 60 msec

5 192.168.1.1 [MPLS: Label 510 Exp 0] 92 msec 60 msec 44 msec

6 192.168.1.2 52 msec 64 msec 64 msec

R1-PE1#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

R1-PE1(config)#no mpls ?

discovery Configure LSP discovery

export Configure periodic export of MPLS PAL table

ip Dynamic MPLS forwarding for IP

label Label properties

ldp Label Distribution Protocol

oam OAM configuration

static MPLS static application

traffic-eng Configure Traffic Engineering parameters

R1-PE1(config)#no mpls ip ?

default-route Allow MPLS forwarding for ip default route

propagate-ttl Propagate IP TTL into the label stack

ttl-expiration Control MPLS TTL expiration behavior

<cr>

R1-PE1(config)#no mpls ip propagate-ttl // HIDES MPLS LABELS FOR CE TO CE ROUTER TRACEROUTE

R2-P1#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

R2-P1(config)#no mpls ip propagate-ttl

R3-P2#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

R3-P2(config)#no mpls ip propagate-ttl

R4-P3#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

R4-P3(config)#no mpls ip propagate-ttl

R5-PE2#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

R5-PE2(config)#no mpls ip propagate-ttl

CUSTA-SITE1#traceroute 192.168.1.99

Type escape sequence to abort.

Tracing the route to 192.168.1.99

VRF info: (vrf in name/id, vrf out name/id)

1 172.16.1.1 16 msec 16 msec 16 msec

2 192.168.1.1 [MPLS: Label 510 Exp 0] 88 msec 80 msec 80 msec // CISCO DEVICE USES UDP IN TRACEROUTE; HIDES P ROUTER/LABELS

3 192.168.1.2 88 msec 100 msec 132 msec

R1-PE1#traceroute vrf CUSTA 192.168.1.99

Type escape sequence to abort.

Tracing the route to 192.168.1.99

VRF info: (vrf in name/id, vrf out name/id)

1 192.168.1.1 [MPLS: Label 510 Exp 0] 140 msec 88 msec 52 msec // SEES DESTINATION IP AS ONE HOP

2 192.168.1.2 100 msec 96 msec 40 msec

R1-PE1#ping ?

WORD Ping destination address or hostname

atm ATM echo

clns CLNS echo

ethernet Ethernet echo

ip IP echo

ipv6 IPv6 echo

mpls MPLS echo

srb srb echo

tag Tag encapsulated IP echo

vrf Select VPN routing instance

<cr>

R1-PE1#ping mpls ?

ipv4 Target specified as an IPv4 address

pseudowire Target VC specified as an IPv4 address and VC ID

traffic-eng Target specified as TE tunnel interface

<cr>

R1-PE1#ping mpls ipv4 ?

A.B.C.D {/nn || A.B.C.D} Target FEC address with mask

R1-PE1#ping mpls ipv4 10.5.5.5/32

Sending 5, 100-byte MPLS Echos to 10.5.5.5/32,

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 = 40/49/60 ms

R1-PE1#ping mpls ipv4 10.5.5.5/32 ?

destination Destination address or address range

dsmap Request dsmap from replying router

exp EXP bits in mpls header

flags Flag options

force-explicit-null force an explicit null label to be added

interval Send interval between requests in msec

output Output options

pad Pad TLV pattern

repeat Repeat count

reply Reply mode

revision Echo Packet TLV versioning

size Packet size

source Source specified as an IP address

sweep Sweep range of sizes

timeout Timeout in seconds

ttl Time to live

verbose verbose output mode

<cr>

R1-PE1#ping mpls ipv4 10.5.5.5/32 verbose

Sending 5, 100-byte MPLS Echos to 10.5.5.5/32,

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.

! size 100, reply addr 10.45.0.5, return code 3 // ! INDICATES MPLS PING OK; MPLS PING USES UDP PORT 3503; RETURN CODE 3 INDICATES THE EGRESS LSR (R5-PE2) IN LSP RESPONDED AN ECHO REPLY

! size 100, reply addr 10.45.0.5, return code 3

Success rate is 100 percent (5/5), round-trip min/avg/max = 40/48/56 ms

R1-PE1#traceroute ?

WORD Trace route to destination address or hostname

appletalk AppleTalk Trace

clns ISO CLNS Trace

ethernet Ethernet Traceroute

ip IP Trace

ipv6 IPv6 Trace

ipx IPX Trace

mpls MPLS LSP Trace

vrf Select VPN routing instance

<cr>

R1-PE1#traceroute mpls ?

ipv4 Target specified as an IPv4 address

multipath LSP Multipath Traceroute

traffic-eng Target specified as TE tunnel interface

<cr>

R1-PE1#traceroute mpls ipv4 ?

A.B.C.D {/nn || A.B.C.D} Target FEC address with mask

R1-PE1#traceroute mpls ipv4 10.5.5.5/32 // TO VERIFY MPLS LSP OR IF USING NATIVE IP

Tracing MPLS Label Switched Path to 10.5.5.5/32, timeout is 2 seconds

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.

0 10.12.0.1 MRU 1500 [Labels: 205 Exp: 0]

L 1 10.12.0.2 MRU 1500 [Labels: 309 Exp: 0] 40 ms

L 2 10.23.0.3 MRU 1500 [Labels: 405 Exp: 0] 48 ms

L 3 10.34.0.4 MRU 1504 [Labels: implicit-null Exp: 0] 52 ms // PHP

! 4 10.45.0.5 44 ms // NATIVE IPv4

R1-PE1#traceroute mpls ipv4 10.5.5.5/32 ?

destination Destination address or address range

exp EXP bits in mpls header

flags Flag options

force-explicit-null force an explicit null label to be added

output Output options

reply Reply mode

revision Echo Packet TLV versioning

source Source specified as an IP address

timeout Timeout in seconds

ttl Maximum time to live

verbose verbose output mode

<cr>

R1-PE1#traceroute mpls ipv4 10.5.5.5/32 verbose

Tracing MPLS Label Switched Path to 10.5.5.5/32, timeout is 2 seconds

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.

0 10.12.0.1 10.12.0.2 MRU 1500 [Labels: 205 Exp: 0] // MAXIMUM RECEIVE UNIT (MRU)

L 1 10.12.0.2 10.23.0.3 MRU 1500 [Labels: 303 Exp: 0] 60 ms, ret code 8 // L INDICATES DOWNSTREAM ROUTER SENDS AN ECHO REPLY; RETURN CODE 8 INDICATES THE PACKET WAS CORRECTLY LABELED BUT IT'S NOT THE TARGET EGRESS LSR

L 2 10.23.0.3 10.34.0.4 MRU 1500 [Labels: 415 Exp: 0] 56 ms, ret code 8

L 3 10.34.0.4 10.45.0.5 MRU 1504 [Labels: implicit-null Exp: 0] 52 ms, ret code 8

! 4 10.45.0.5 60 ms, ret code 3 // RETURN CODE 3 INDICATES EGRESS LSR IN LSP

R3-P2#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

R3-P2(config)#no mpls ip

R3-P2(config)#

*Dec 11 09:39:12.541: %LDP-5-NBRCHG: LDP Neighbor 10.2.2.2:0 (3) is DOWN (LDP unconfigured globally)

*Dec 11 09:39:12.545: %LDP-5-NBRCHG: LDP Neighbor 10.4.4.4:0 (4) is DOWN (LDP unconfigured globally)

R3-P2(config)#

*Dec 11 09:39:16.757: %MPLS_PACKET-4-NOLFDSB: MPLS packet received on non MPLS enabled interface FastEthernet1/1 L3 type 0x8847 label {303 0 1 1}

R2-P1#

*Dec 11 09:39:11.097: %LDP-5-NBRCHG: LDP Neighbor 10.3.3.3:0 (1) is DOWN (TCP connection closed by peer)

R4-P3(config)#

*Dec 11 09:39:20.181: %LDP-5-NBRCHG: LDP Neighbor 10.3.3.3:0 (2) is DOWN (TCP connection closed by peer)

R1-PE1#traceroute mpls ipv4 10.5.5.5/32

Tracing MPLS Label Switched Path to 10.5.5.5/32, timeout is 2 seconds

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.

0 10.12.0.1 MRU 1500 [Labels: 205 Exp: 0]

B 1 10.12.0.2 MRU 1504 [No Label] 12 ms // ISSUE OR A BREAK IN LSP

. 2 *

B 3 10.12.0.2 MRU 1504 [No Label] 28 ms

B 4 10.12.0.2 MRU 1504 [No Label] 36 ms

B 5 10.12.0.2 MRU 1504 [No Label] 40 ms

B 6 10.12.0.2 MRU 1504 [No Label] 24 ms

B 7 10.12.0.2 MRU 1504 [No Label] 44 ms

B 8 10.12.0.2 MRU 1504 [No Label] 20 ms

B 9 10.12.0.2 MRU 1504 [No Label] 40 ms

B 10 10.12.0.2 MRU 1504 [No Label] 44 ms

B 11 10.12.0.2 MRU 1504 [No Label] 40 ms

B 12 10.12.0.2 MRU 1504 [No Label] 40 ms

B 13 10.12.0.2 MRU 1504 [No Label] 36 ms

B 14 10.12.0.2 MRU 1504 [No Label] 40 ms

B 15 10.12.0.2 MRU 1504 [No Label] 40 ms

B 16 10.12.0.2 MRU 1504 [No Label] 40 ms

B 17 10.12.0.2 MRU 1504 [No Label] 36 ms

B 18 10.12.0.2 MRU 1504 [No Label] 44 ms

B 19 10.12.0.2 MRU 1504 [No Label] 40 ms

B 20 10.12.0.2 MRU 1504 [No Label] 36 ms

B 21 10.12.0.2 MRU 1504 [No Label] 40 ms

B 22 10.12.0.2 MRU 1504 [No Label] 36 ms

B 23 10.12.0.2 MRU 1504 [No Label] 40 ms

B 24 10.12.0.2 MRU 1504 [No Label] 40 ms

B 25 10.12.0.2 MRU 1504 [No Label] 36 ms

B 26 10.12.0.2 MRU 1504 [No Label] 72 ms

B 27 10.12.0.2 MRU 1504 [No Label] 56 ms

B 28 10.12.0.2 MRU 1504 [No Label] 40 ms

B 29 10.12.0.2 MRU 1504 [No Label] 40 ms

B 30 10.12.0.2 MRU 1504 [No Label] 40 ms

R1-PE1#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

R1-PE1(config)#no mpls ip propagate-ttl ?

forwarded Propagate IP TTL for forwarded traffic

local Propagate IP TTL for locally originated traffic

<cr>

R1-PE1(config)#no mpls ip propagate-ttl forwarded // HIDES MPLS LABELS FOR CE TO CE ROUTER BUT NOT FOR MPLS VPN NETWORK: PE <> P <> PE

R2-P1#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

R2-P1(config)#no mpls ip propagate-ttl forwarded

R3-P2#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

R3-P2(config)#no mpls ip propagate-ttl forwarded

R4-P3#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

R4-P3(config)#no mpls ip propagate-ttl forwarded

R5-PE2#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

R5-PE2(config)#no mpls ip propagate-ttl forwarded

CUSTA-SITE1#traceroute 192.168.1.99

Type escape sequence to abort.

Tracing the route to 192.168.1.99

VRF info: (vrf in name/id, vrf out name/id)

1 172.16.1.1 52 msec 100 msec 24 msec

2 192.168.1.1 [MPLS: Label 510 Exp 0] 92 msec 96 msec 44 msec

3 192.168.1.2 92 msec 36 msec 116 msec

R1-PE1#traceroute vrf CUSTA 192.168.1.99

Type escape sequence to abort.

Tracing the route to 192.168.1.99

VRF info: (vrf in name/id, vrf out name/id)

1 10.12.0.2 [MPLS: Labels 205/510 Exp 0] 116 msec 68 msec 68 msec

2 10.23.0.3 [MPLS: Labels 309/510 Exp 0] 64 msec 60 msec 60 msec

3 10.34.0.4 [MPLS: Labels 405/510 Exp 0] 76 msec 64 msec 40 msec

4 192.168.1.2 84 msec 64 msec 44 msec

R1-PE1#show mpls forwarding-table // LFIB ACCOUNTING PER LSP

Local Outgoing Prefix Bytes Label Outgoing Next Hop

Label Label or Tunnel Id Switched interface

100 Pop Label 10.2.2.2/32 0 Fa0/0 10.12.0.2

101 Pop Label 10.23.0.0/24 0 Fa0/0 10.12.0.2

102 201 10.3.3.3/32 0 Fa0/0 10.12.0.2

103 202 10.34.0.0/24 0 Fa0/0 10.12.0.2

104 203 10.4.4.4/32 0 Fa0/0 10.12.0.2

105 204 10.45.0.0/24 0 Fa0/0 10.12.0.2

106 205 10.5.5.5/32 0 Fa0/0 10.12.0.2

107 No Label 172.16.1.0/30[V] 38614 aggregate/CUSTA

108 No Label 172.16.1.99/32[V] \

0 Fa1/0 172.16.1.2

109 No Label 172.16.1.0/30[V] 15940 aggregate/CUSTB

110 No Label 172.16.1.100/32[V] \

0 Fa1/1 172.16.1.2

R5-PE2#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

R5-PE2(config)#access-list ?

<1-99> IP standard access list

<100-199> IP extended access list

<1100-1199> Extended 48-bit MAC address access list

<1300-1999> IP standard access list (expanded range)

<200-299> Protocol type-code access list

<2000-2699> IP extended access list (expanded range)

<2700-2799> MPLS access list

<700-799> 48-bit MAC address access list

compiled Enable IP access-list compilation

dynamic-extended Extend the dynamic ACL absolute timer

rate-limit Simple rate-limit specific access list

R5-PE2(config)#access-list 2701 ?

deny Specify packets to reject

permit Specify packets to forward

remark access list entry comment

R5-PE2(config)#access-list 2701 permit ?

WORD mpls label table name or 'any'

R5-PE2(config)#access-list 2701 permit any ?

<0-1048575> mpls label number

any any label number

<cr>

R5-PE2(config)#access-list 2701 permit any any ?

<0-7> mpls exp value

any any exp value

<cr>

R5-PE2(config)#access-list 2701 permit any any any ?

<0-1> mpls eos value

any any eos value

<cr>

R5-PE2(config)#access-list 2701 permit any any any any ?

<cr>

R5-PE2(config)#access-list 2701 permit any any any any

R5-PE2(config)#end

R5-PE2#

*Nov 30 23:03:16.043: %SYS-5-CONFIG_I: Configured from console by console

R5-PE2#debug mpls ?

access-list MPLS ACCESS

events MPLS events

ip Debug MPLS IP information

l2transport Any transport over MPLS debug

ldp Label Distribution Protocol

lspv LSP Verification debug

netflow MPLS Egress NetFlow Accounting

packet mpls packet debug

static MPLS Static labels

traffic-eng MPLS Traffic Engineering debug

R5-PE2#debug mpls packet ?

<2700-2799> MPLS label access list

Async Async interface

Auto-Template Auto-Template interface

BVI Bridge-Group Virtual Interface

CDMA-Ix CDMA Ix interface

CTunnel CTunnel interface

Dialer Dialer interface

FastEthernet FastEthernet IEEE 802.3

GMPLS MPLS interface

LISP Locator/ID Separation Protocol Virtual Interface

LongReachEthernet Long-Reach Ethernet interface

Loopback Loopback interface

MFR Multilink Frame Relay bundle interface

Multilink Multilink-group interface

Null Null interface

Port-channel Ethernet Channel of interfaces

Tunnel Tunnel interface

Vif PGM Multicast Host interface

Virtual-PPP Virtual PPP interface

Virtual-Template Virtual Template interface

Virtual-TokenRing Virtual TokenRing

error error conditions

exception exception conditions

process process packet information

rate-limit rate limit mpls packet debugs

vmi Virtual Multipoint Interface

<cr>

R5-PE2#debug mpls packet 2701 // CAUTION IS NEEDED WHEN DEBUGGING MPLS; LIMIT INFO WITH ACL

R5-PE2#debug mpls events

MPLS events debugging is on

R5-PE2#

R5-PE2#debug mpls packet

Packet debugging is on

R4-P3#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

R4-P3(config)#no mpls ip

R4-P3(config)#

*Nov 30 23:08:13.911: %LDP-5-NBRCHG: LDP Neighbor 10.3.3.3:0 (1) is DOWN (LDP unconfigured globally)

*Nov 30 23:08:13.915: %LDP-5-NBRCHG: LDP Neighbor 10.5.5.5:0 (2) is DOWN (LDP unconfigured globally)

R4-P3(config)#

*Nov 30 23:08:14.715: %MPLS_PACKET-4-NOLFDSB: MPLS packet received on non MPLS enabled interface FastEthernet1/0 L3 type 0x8847 label {409 6 1 253}

R4-P3(config)#

R4-P3(config)#mpls ip

R4-P3(config)#

*Nov 30 23:08:31.311: %LDP-5-NBRCHG: LDP Neighbor 10.5.5.5:0 (1) is UP

*Nov 30 23:08:31.379: %LDP-5-NBRCHG: LDP Neighbor 10.3.3.3:0 (2) is UP

R5-PE2#

*Nov 30 23:08:14.275: %LDP-5-NBRCHG: LDP Neighbor 10.4.4.4:0 (1) is DOWN (TCP connection closed by peer)

R5-PE2#

*Nov 30 23:08:31.515: %LDP-5-NBRCHG: LDP Neighbor 10.4.4.4:0 (1) is UP

R5-PE2#

*Nov 30 23:08:41.611: MPLS turbo: Fa0/0: rx: Len 190 Stack {510 6 253} - ipv4 data s:10.12.0.2 d:172.16.1.1 ttl:255 tos:C0 prot:1 // {LABEL EXP TTL}

*Nov 30 23:08:41.707: MPLS turbo: Fa0/0: rx: Len 190 Stack {510 6 253} - ipv4 data s:10.12.0.2 d:172.16.1.1 ttl:255 tos:C0 prot:1

*Nov 30 23:08:41.763: MPLS turbo: Fa0/0: rx: Len 190 Stack {510 6 253} - ipv4 data s:10.12.0.2 d:172.16.1.1 ttl:255 tos:C0 prot:1

*Nov 30 23:08:41.815: MPLS turbo: Fa0/0: rx: Len 190 Stack {510 6 254} - ipv4 data s:10.23.0.3 d:172.16.1.1 ttl:255 tos:C0 prot:1

*Nov 30 23:08:41.883: MPLS turbo: Fa0/0: rx: Len 190 Stack {510 6 254} - ipv4 data s:10.23.0.3 d:172.16.1.1 ttl:255 tos:C0 prot:1

R5-PE2#

*Nov 30 23:08:41.931: MPLS turbo: Fa0/0: rx: Len 190 Stack {510 6 254} - ipv4 data s:10.23.0.3 d:172.16.1.1 ttl:255 tos:C0 prot:1

*Nov 30 23:08:41.995: MPLS turbo: Fa0/0: rx: Len 190 Stack {510 6 255} - ipv4 data s:10.34.0.4 d:172.16.1.1 ttl:255 tos:C0 prot:1

*Nov 30 23:08:42.067: MPLS turbo: Fa0/0: rx: Len 190 Stack {510 6 255} - ipv4 data s:10.34.0.4 d:172.16.1.1 ttl:255 tos:C0 prot:1

*Nov 30 23:08:42.115: MPLS turbo: Fa0/0: rx: Len 190 Stack {510 6 255} - ipv4 data s:10.34.0.4 d:172.16.1.1 ttl:255 tos:C0 prot:1

*Nov 30 23:08:42.175: MPLS turbo: Fa0/0: rx: Len 56 Stack {510 0 1} - ipv4 data s:172.16.1.1 d:192.168.1.99 ttl:4 tos:0 prot:11

*Nov 30 23:08:42.175: FIBfwd-proc: packet routed to FastEthernet1/0 192.168.1.2(1)

*Nov 30 23:08:42.179: FIBfwd-proc: ip_pak_table 1 ip_nh_table 65535 if FastEthernet1/0 nh 192.168.1.2 uhp 1 deag 0 ttlexp 1

*Nov 30 23:08:42.179: FIBfwd-proc: CUSTA:172.16.1.0/30 process level forwarding

*Nov 30 23:08:42.179: FIBfwd-proc: depth 0 first_idx 0

R5-PE2# paths 1 long 0(0)

*Nov 30 23:08:42.179: FIBfwd-proc: try path 0 (of 1) v4-rcrsv-10.1.1.1 first short ext 6AA1435C(0)

*Nov 30 23:08:42.179: FIBfwd-proc: v4-rcrsv-10.1.1.1 valid short mbl

*Nov 30 23:08:42.179: FIBfwd-proc: label[0] 107 connid 0 link ILLEGAL

*Nov 30 23:08:42.179: FIBfwd-proc: ip_pak_table 1 ip_nh_table 0 if none nh 10.1.1.1 deag 0 chg_if 0 via fib 6A95F444 path type recursive

*Nov 30 23:08:42.179: FIBfwd-proc: depth 1 first_idx 0 paths 1 long 0(0)

*Nov 30 23:08:42.179: FIBfwd-proc: try path 0 (of 1) v4-anh-10.45.0.4-Fa0/0 first short ext 67A72DBC(0)

*Nov 30 23:08:42.179: FIBfwd-proc: v4-anh-10.45.0.4-Fa0/0 valid short

*Nov 30 23:08:42.179: FIBfwd-proc: label[1] 412 connid 0 link TAG

*Nov 30 23:08:42.183: FIBfwd-proc: ip_pak_table 1 ip_nh_table 65535 if FastEthernet0/0 nh 10.45.0.4 deag 0 chg_if 0 via fib 0 path type attached nexthop

*Nov 30 23:08:42.187: FIBfwd-proc: packet routed to FastEthernet0/0 10.45.0.4(1) with labels 107 412

*Nov 30 23:08:42.191: FIBip

R5-PE2#v4-packet-proc: packet routing succeeded

*Nov 30 23:08:42.191: FIBfwd-proc: ip_pak_table 1 ip_nh_table 65535 if FastEthernet0/0 nh 10.45.0.4 uhp 0 deag 0 ttlexp 0

*Nov 30 23:08:42.195: FIBfwd-proc: sending link TAG ip_pak_table 1 ip_nh_table 65535 if FastEthernet0/0 nh 10.45.0.4 uhp 0 deag 0 chgif 0 ttlexp 0 rec 0

*Nov 30 23:08:42.239: MPLS turbo: Fa0/0: rx: Len 56 Stack {510 0 1} - ipv4 data s:172.16.1.1 d:192.168.1.99 ttl:4 tos:0 prot:11

*Nov 30 23:08:42.243: FIBfwd-proc: packet routed to FastEthernet1/0 192.168.1.2(1)

*Nov 30 23:08:42.243: FIBfwd-proc: ip_pak_table 1 ip_nh_table 65535 if FastEthernet1/0 nh 192.168.1.2 uhp 1 deag 0 ttlexp 1

*Nov 30 23:08:42.243: FIBfwd-proc: CUSTA:172.16.1.0/30 process level forwarding

*Nov 30 23:08:42.243: FIBfwd-proc: depth 0 first_idx 0 paths 1 long 0(0)

*Nov 30 23:08:42.243: FIBfwd-proc: try path 0 (of 1) v4-rcrsv-10.1.1.1 first short ext 6AA1435C(0)

*Nov 30 23:08:42.243: FIBfwd-proc: v4-rcrsv-10.1.1.1 valid short mbl

*Nov 30 23:08:42.

R5-PE2#243: FIBfwd-proc: label[0] 107 connid 0 link ILLEGAL

*Nov 30 23:08:42.243: FIBfwd-proc: ip_pak_table 1 ip_nh_table 0 if none nh 10.1.1.1 deag 0 chg_if 0 via fib 6A95F444 path type recursive

*Nov 30 23:08:42.243: FIBfwd-proc: depth 1 first_idx 0 paths 1 long 0(0)

*Nov 30 23:08:42.243: FIBfwd-proc: try path 0 (of 1) v4-anh-10.45.0.4-Fa0/0 first short ext 67A72DBC(0)

*Nov 30 23:08:42.243: FIBfwd-proc: v4-anh-10.45.0.4-Fa0/0 valid short

*Nov 30 23:08:42.243: FIBfwd-proc: label[1] 412 connid 0 link TAG

*Nov 30 23:08:42.243: FIBfwd-proc: ip_pak_table 1 ip_nh_table 65535 if FastEthernet0/0 nh 10.45.0.4 deag 0 chg_if 0 via fib 0 path type attached nexthop

*Nov 30 23:08:42.243: FIBfwd-proc: packet routed to FastEthernet0/0 10.45.0.4(1) with labels 107 412

*Nov 30 23:08:42.243: FIBipv4-packet-proc: packet routing succeeded

*Nov 30 23:08:42.243: FIBfwd-proc: ip_pak_table 1 ip_nh_table 65535 if FastEthernet0/0 nh 10.45.0.4 uhp 0 deag 0 ttlexp 0

*Nov 30 23:08:42.243: FIBfwd-proc: sending

R5-PE2# link TAG ip_pak_table 1 ip_nh_table 65535 if FastEthernet0/0 nh 10.45.0.4 uhp 0 deag 0 chgif 0 ttlexp 0 rec 0

*Nov 30 23:08:42.283: MPLS turbo: Fa0/0: rx: Len 56 Stack {510 0 1} - ipv4 data s:172.16.1.1 d:192.168.1.99 ttl:4 tos:0 prot:11

*Nov 30 23:08:42.283: FIBfwd-proc: packet routed to FastEthernet1/0 192.168.1.2(1)

*Nov 30 23:08:42.283: FIBfwd-proc: ip_pak_table 1 ip_nh_table 65535 if FastEthernet1/0 nh 192.168.1.2 uhp 1 deag 0 ttlexp 1

*Nov 30 23:08:42.283: FIBfwd-proc: CUSTA:172.16.1.0/30 process level forwarding

*Nov 30 23:08:42.283: FIBfwd-proc: depth 0 first_idx 0 paths 1 long 0(0)

*Nov 30 23:08:42.283: FIBfwd-proc: try path 0 (of 1) v4-rcrsv-10.1.1.1 first short ext 6AA1435C(0)

*Nov 30 23:08:42.283: FIBfwd-proc: v4-rcrsv-10.1.1.1 valid short mbl

*Nov 30 23:08:42.283: FIBfwd-proc: label[0] 107 connid 0 link ILLEGAL

*Nov 30 23:08:42.283: FIBfwd-proc: ip_pak_table 1 ip_nh_table 0 if none nh 10.1.1.1 deag 0 chg_if 0 via fib 6A95F444 path type recursive

*Nov 30 23:08:42.283: FIBfwd-proc: depth 1 first_idx 0 paths 1 long 0(0)

*Nov 30 23:08:42.283: FIBfwd-proc: try path 0 (of 1) v4-anh-10.45.0.4-Fa0/0 first short ext 67A72DBC(0)

*No

R5-PE2#v 30 23:08:42.283: FIBfwd-proc: v4-anh-10.45.0.4-Fa0/0 valid short

*Nov 30 23:08:42.283: FIBfwd-proc: label[1] 412 connid 0 link TAG

*Nov 30 23:08:42.283: FIBfwd-proc: ip_pak_table 1 ip_nh_table 65535 if FastEthernet0/0 nh 10.45.0.4 deag 0 chg_if 0 via fib 0 path type attached nexthop

*Nov 30 23:08:42.283: FIBfwd-proc: packet routed to FastEthernet0/0 10.45.0.4(1) with labels 107 412

*Nov 30 23:08:42.283: FIBipv4-packet-proc: packet routing succeeded

*Nov 30 23:08:42.283: FIBfwd-proc: ip_pak_table 1 ip_nh_table 65535 if FastEthernet0/0 nh 10.45.0.4 uhp 0 deag 0 ttlexp 0

*Nov 30 23:08:42.283: FIBfwd-proc: sending link TAG ip_pak_table 1 ip_nh_table 65535 if FastEthernet0/0 nh 10.45.0.4 uhp 0 deag 0 chgif 0 ttlexp 0 rec 0

*Nov 30 23:08:42.323: MPLS turbo: Fa0/0: rx: Len 56 Stack {510 0 2} - ipv4 data s:172.16.1.1 d:192.168.1.99 ttl:5 tos:0 prot:11

*Nov 30 23:08:42.367: MPLS turbo: Fa0/0: rx: Len 56 Stack {510 0 2} - ipv4 data s:172.16.1.1 d:192.168.1.99 ttl:5 tos:0 prot:11

*Nov

R5-PE2# 30 23:08:42.419: MPLS turbo: Fa0/0: rx: Len 56 Stack {510 0 2} - ipv4 data s:172.16.1.1 d:192.168.1.99 ttl:5 tos:0 prot:11

*Nov 30 23:08:44.587: tagcon: background scan: Start

*Nov 30 23:08:44.587: tagcon: background scan: End

R5-PE2#

R5-PE2#undebug all

All possible debugging has been turned off

My Network Lab

Friday, May 17, 2019

Troubleshooting an MPLS VPN Network