Topology-Independent Loop-Free Alternate
The term topology independent (TI) refers to the ability to provide a loop free backup path irrespective of the topologies used in the network. Topology-Independent Loop-Free Alternate (TI-LFA) uses segment routing to provide link, node and Shared Risk Link Groups (SRLG) protection in topologies where other fast reroute techniques, such as RLFA (Remote Loop Free Alternative) cannot provide protection. Currently, OSPF SR-TI-LFA supports only link protection.
The goal of TI-LFA is to reduce the packet loss that results while routers converge after a topology change due to a link failure. Rapid failure repair (up to 50msec) is achieved using pre-calculated backup paths that are loop-free.
Terminology
PLR : Point of Local Repair : The node that is just upstream of the protected resource. This node notices that the protected resource(link/node/set-of-links) is broken first and uses an FRR mechanism to protect that resource
Repair Node : The node to which the PLR wants to get the traffic to during the convergence period, once the protected resource fails, because the repair node is guanteed to have a path to the destination 'D'
Pre-Convergence State : A source 'S' is said to be in a pre-convergence state regarding a particular destination 'D' from the time the primary-path to 'D' fails until 'S' installs a new route to 'D'
Post-Convergence State : A source 'S' is said to be in a post-convergence state regarding a particular destination 'D' after it installs a new route to 'D'
P-space: The P-space of a router with respect to a protected link is the set of routers reachable from that specific router using the pre-convergence shortest paths without any of those paths (including equal-cost path splits) transiting that protected link.For example, the P-space of S with respect to link S-E is the set of routers that S can reach without using the protected link S-E
Extended P-space: Consider the set of neighbors of a router protecting a link. Exclude from that set of routers the router reachable over the protected link. The extended P-space of the protecting router with respect to the protected link is the union of the P-spaces of the neighbors in that set of neighbors with respect to the protected link
Q-space: The Q-space of a router with respect to a protected link is the set of routers from which that specific router can be reached without any path (including equal-cost path splits) transiting that protected link 
PQ node: A PQ node of a node S with respect to a protected link S-E is a node that is a member of both the P-space (or the extended P-space) of S with respect to that protected link S-E and the Q-space of E with respect to that protected link S-E.
Difference betweem LFA/RLFA/TI-LFA
LFA : 
•		The repair node is restricted to be the neighbor of the PLR
RLFA :
•		The repair node is not restricted to be the direct neighbor of the PLR. It can be a node from the PQ-space.
•		A repair tunnel would be created from the PLR to the repair node and this repair tunnel traverses the IGP shortest-path from the PLR to the repair node 
•		The repair tunnel can be LDP-signalled(Targeted LDP session required from the PLR to the repair node )
TI-LFA:
•		SR-paths can be used as repair tunnels.Because the repair tunnel is an SR-path, it is not required to traverse the IGP shortest-path from the PLR to the repair node.It can be any viable path that can be specified by the PLR as an ordered list of segments. 
•		Thus, the repair node can be outside of the PLR's P-space.
•		However, the repair node must be within the destination node's Q-space. Sometimes, the repair node is also the destination node.
•		No TLDP session required in case of TI-LFA as TI-LFA uses segment-routing thus eliminating the overhead of maintaining any state
Topology
 
TI-LFA FRR path using a PQ Node
Note:	It should be ensured that prefix SIDs are unique globally.
Note:	By default, the CSPF retry limit is 10 times and the CSPF retry interval is 10 seconds. If a policy does not come up within 100 seconds, it will require operator intervention.
TI-LFA FRR Path using a PQ node with OSPF-SR
PE1
 
| PE1#configure terminal | Enter configure mode. | 
| PE1(config)#interface lo | Enter interface mode. | 
| PE1(config-if)#ip address 1.1.1.1/32 secondary | Configure the IP address of the interface. | 
| PE1(config-if)#prefix-sid index 1 | Configure prefix SID index value. | 
| PE1(config-if)#exit | Exit interface mode. | 
| PE1(config)#interface eth1 | Enter interface mode. | 
| PE1(config-if)#ip address 10.1.2.1/32 secondary | Configure the IP address of the interface. | 
| PE1(config-if)#label-switching | Enable label switching. | 
| PE1(config-if)#exit | Exit interface mode | 
| PE1(config)#router ospf 100 | Set the routing process ID . | 
| PE1(config-router)#ospf router-id 1.1.1.1 | Configuring OSPF router-id | 
| PE1(config-router)#network 1.1.1.1/32 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| PE1(config-router)#network 10.1.2.0/24 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| PE1(config-router)#segment-routing mpls | Enable segment routing under router OSPF process. | 
| PE1(config-router)#exit | Exit router mode. | 
| PE1(config)#exit | Exit configure mode | 
| PE1(config)#commit | Commit the candidate configuration to the running configuration. | 
P1
 
| P1#configure terminal | Enter configure mode. | 
| P1(config)#interface lo | Enter interface mode. | 
| P1(config-if)#ip address 1.1.1.2/32 secondary | Configure the IP address of the interface. | 
| P1(config-if)#prefix-sid index 2 | Configure prefix SID index value. | 
| P1(config-if)#exit | Exit interface mode. | 
| P1(config)#interface eth1 | Enter interface mode. | 
| P1(config-if)#ip address 10.1.2.2/32 secondary | Configure the IP address of the interface. | 
| P1(config-if)#label-switching | Enable label switching. | 
| P1(config-if)#exit | Exit interface mode. | 
| P1(config)#interface eth2 | Enter interface mode. | 
| P1(config-if)#ip address 10.2.3.1/32 secondary | Configure the IP address of the interface. | 
| P1(config-if)#label-switching | Enable label switching. | 
| P1(config-if)#exit | Exit interface mode. | 
| P1(config)#interface eth3 | Enter interface mode. | 
| P1(config-if)#ip address 10.2.6.1/32 secondary | Configure the IP address of the interface. | 
| P1(config-if)#label-switching | Enable label switching. | 
| P1(config-if)#exit | Exit interface mode. | 
| P1(config)#router ospf 100 | Set the routing process ID . | 
| P1(config-router)#ospf router-id 1.1.1.2/32 secondary | Configure OSPF router-id | 
| P1(config-router)#network 1.1.1.2/32 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| P1(config-router)#network 10.1.2.0/24 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| P1(config-router)#network 10.2.3.0/24 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| P1(config-router)#network 10.2.6.0/24 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| P1(config-router)#segment-routing mpls | Enable segment routing under router process. | 
| P1(config-router)# fast-reroute per-prefix ti-lfa area 0.0.0.0 | Enable per-prefix TI-LFA FRR computation for OSPF area 0  | 
| P1(config-router)#exit | Exit router mode. | 
| P1(config)#exit | Exit configure mode | 
| P1(config)#commit | Commit the candidate configuration to the running configuration. | 
P2
 
| P2#configure terminal | Enter configure mode. | 
| P2(config)#interface lo | Enter interface mode. | 
| P2(config-if)#ip address 1.1.1.3/32 secondary | Configure the IP address of the interface. | 
| P2(config-if)#prefix-sid index 3 | Configure prefix SID index value. | 
| P2(config-if)#exit | Exit interface mode. | 
| P2(config)#interface eth1 | Enter interface mode. | 
| P2(config-if)#ip address 10.3.4.1/32 secondary | Configure the IP address of the interface. | 
| P2(config-if)#label-switching | Enable label switching. | 
| P2(config-if)#exit | Exit interface mode. | 
| P2(config)#interface eth2 | Enter interface mode. | 
| P2(config-if)#ip address 10.2.3.2/32 secondary | Configure the IP address of the interface. | 
| P2(config-if)#label-switching | Enable label switching. | 
| P2(config-if)#exit | Exit interface mode. | 
| P2(config)#interface eth3 | Enter interface mode. | 
| P2(config-if)#ip address 10.3.7.1/32 secondary | Configure the IP address of the interface. | 
| P2(config-if)#label-switching | Enable label switching. | 
| P2(config-if)#exit | Exit interface mode. | 
| P2(config)#router ospf 100 | Set the routing process ID . | 
| P2(config-router)#ospf router-id 1.1.1.3/32 secondary | Configure OSPF router-id | 
| P2(config-router)#network 1.1.1.3/32 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| P2(config-router)#network 10.3.4.0/32 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| P2(config-router)#network 10.2.3.0/32 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| P2(config-router)#network 10.3.7.0/32 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| P2(config-router)#segment-routing mpls | Enable segment routing under router process. | 
| P2(config-router)#exit | Exit router mode. | 
| P2(config)#exit | Exit configure mode | 
| P2(config)#commit | Commit the candidate configuration to the running configuration. | 
P3
 
| P3#configure terminal | Enter configure mode. | 
| P3(config)#interface lo | Enter interface mode. | 
| P3(config-if)#ip address 1.1.1.4/32 secondary | Configure the IP address of the interface. | 
| P3(config-if)#prefix-sid index 4 | Configure prefix SID index value. | 
| P3(config-if)#exit | Exit interface mode. | 
| P3(config)#interface eth1 | Enter interface mode. | 
| P3(config-if)#ip address 10.3.4.2/32 secondary | Configure the IP address of the interface. | 
| P3(config-if)#label-switching | Enable label switching. | 
| P3(config-if)#exit | Exit interface mode. | 
| P3(config)#interface eth2 | Enter interface mode. | 
| P3(config-if)#ip address 10.4.5.1/32 secondary | Configure the IP address of the interface. | 
| P3(config-if)#label-switching | Enable label switching. | 
| P3(config-if)#exit | Exit interface mode. | 
| P3(config)#router ospf 100 | Set the routing process ID . | 
| P3(config-router)#ospf router-id 1.1.1.4/32 secondary | Configure OSPF router-id | 
| P3(config-router)#network 1.1.1.4/32 area 0.0.0.0 | Configure OSPF network in area 0 | 
| P3(config-router)#network 10.3.4.0/32 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| P3(config-router)#network 10.4.5.0/32 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| P3(config-router)#segment-routing mpls | Enable segment routing under router process. | 
| P3(config-router)#exit | Exit router mode. | 
| P3(config)#exit | Exit configure mode | 
| P3(config)#commit | Commit the candidate configuration to the running configuration. | 
P4
 
| P4#configure terminal | Enter configure mode. | 
| P4(config)#interface lo | Enter interface mode. | 
| P4(config-if)#ip address 1.1.1.5/32 secondary | Configure the IP address of the interface. | 
| P4(config-if)#prefix-sid index 5 | Configure prefix SID index value. | 
| P4(config-if)#exit | Exit interface mode. | 
| P4(config)#interface eth1 | Enter interface mode. | 
| P4(config-if)#ip address 10.5.6.1/32 secondary | Configure the IP address of the interface. | 
| P4(config-if)#label-switching | Enable label switching. | 
| P4(config-if)#exit | Exit interface mode. | 
| P4(config)#interface eth2 | Enter interface mode. | 
| P4(config-if)#ip address 10.4.5.2/32 secondary | Configure the IP address of the interface. | 
| P4(config-if)#label-switching | Enable label switching. | 
| P4(config-if)#exit | Exit interface mode. | 
| P4(config)#router ospf 100 | Set the routing process ID . | 
| P4(config-router)#ospf router-id 1.1.1.5/32 secondary | Configure OSPF router-id | 
| P4(config-router)#network 1.1.1.5/32 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| P4(config-router)#network 10.4.5.0/32 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| P4(config-router)#network 10.5.6.0/32 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| P4(config-router)#segment-routing mpls | Enable segment routing under router process. | 
| P4(config-router)#exit | Exit router mode. | 
| P4(config)#exit | Exit configure mode | 
| P4(config)#commit | Commit the candidate configuration to the running configuration. | 
P5
 
| P5#configure terminal | Enter configure mode. | 
| P5(config)#interface lo | Enter interface mode. | 
| P5(config-if)#ip address 1.1.1.6/32 secondary | Configure the IP address of the interface. | 
| P5(config-if)#prefix-sid index 6 | Configure prefix SID index value. | 
| P5(config-if)#exit | Exit interface mode. | 
| P5(config)#interface eth1 | Enter interface mode. | 
| P5(config-if)#ip address 10.5.6.2/32 secondary | Configure the IP address of the interface. | 
| P5(config-if)#label-switching | Enable label switching. | 
| P5(config-if)#exit | Exit interface mode. | 
| P5(config)#interface eth3 | Enter interface mode. | 
| P5(config-if)#ip address 10.2.6.2/32 secondary | Configure the IP address of the interface. | 
| P5(config-if)#label-switching | Enable label switching. | 
| P5(config-if)#exit | Exit interface mode. | 
| P5(config)#router ospf 100 | Set the routing process ID . | 
| P5(config-router)#ospf router-id 1.1.1.6/32 secondary | Configure OSPF router-id | 
| P5(config-router)#network 1.1.1.6/32 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| P5(config-router)#network 10.2.6.0/32 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| P5(config-router)#network 10.5.6.0/32 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| P5(config-router)#segment-routing mpls | Enable segment routing under router process. | 
| P5(config-router)#exit | Exit router mode. | 
| P5(config)#exit | Exit configure mode | 
| P5(config)#commit | Commit the candidate configuration to the running configuration. | 
PE2
 
| PE2#configure terminal | Enter configure mode. | 
| PE2(config)#interface lo | Enter interface mode. | 
| PE2(config-if)#ip address 1.1.1.7/32 secondary | Configure the IP address of the interface. | 
| PE2(config-if)#prefix-sid index 7 | Configure prefix SID index value. | 
| PE2(config-if)#exit | Exit interface mode. | 
| PE2(config)#interface eth3 | Enter interface mode. | 
| PE2(config-if)#ip address 10.3.7.2/32 secondary | Configure the IP address of the interface. | 
| PE2(config-if)#label-switching | Enable label switching. | 
| PE2(config-if)#exit | Exit interface mode. | 
| PE2(config)#router ospf 100 | Set the routing process ID . | 
| PE2(config-router)#ospf router-id 1.1.1.7/32 secondary | Configuring OSPF router-id | 
| PE2(config-router)#network 1.1.1.7/32 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| PE2(config-router)#network 10.3.7.0/32 area 0.0.0.0 secondary | Configure OSPF network in area 0 | 
| PE2(config-router)#segment-routing mpls | Enable segment routing under router OSPF process. | 
| PE2(config-router)#exit | Exit router mode. | 
| PE2(config)#exit | Exit configure mode | 
| PE2(config)#commit | Commit the candidate configuration to the running configuration. | 
Validation 1
Verify OSPF adjacencies on P1
P1#show ip ospf neighbor
 
Total number of full neighbors: 3
OSPF process 100 VRF(default):
Neighbor ID     Pri   State            Dead Time   Address         Interface           Instance ID
1.1.1.1           1   Full/DR          00:00:37    10.1.2.1        eth1                     0
1.1.1.3           1   Full/Backup      00:00:37    10.2.3.2        eth2                     0
1.1.1.6           1   Full/Backup      00:00:32    10.2.6.2        eth3                     0
Validation 2
Verify that the 2 PQ nodes in the topology are P4 (1.1.1.5) and P3 (1.1.1.4).
P4 is the PQ node for PE2 (1.1.1.7/32)
P1
P1#show ip ospf tilfa-backup-path
 
OSPF process 100:
Route [1.1.1.1]
   NO PQ node
Route [1.1.1.2]
Route [1.1.1.3]
   PQ-node: 1.1.1.5
Route [1.1.1.4]
   PQ-node: 1.1.1.5
Route [1.1.1.5]
   PQ-node: 1.1.1.4
Route [1.1.1.6]
   PQ-node: 1.1.1.4
Route [1.1.1.7]
   PQ-node: 1.1.1.5
Route [10.1.2.0]
Route [10.2.3.0]
Route [10.2.6.0]
Route [10.3.4.0]
Route [10.3.7.0]
Route [10.4.5.0]
Route [10.5.6.0]
Neighbor [1.1.1.1]
Neighbor [1.1.1.3]
   PQ-node: 1.1.1.5
Neighbor [1.1.1.6]
   PQ-node: 1.1.1.4
 
Displaying vertex-info in tilfa_network table
Vertex [1.1.1.1]
  P node: 1.1.1.4 dist: 2
  P node: 1.1.1.5 dist: 2
  P node: 1.1.1.7 dist: 2
  P node: 1.1.1.3 dist: 1
  P node: 1.1.1.6 dist: 1
 
Vertex [1.1.1.2]
  No P Nodes
  No Q Nodes
 
Vertex [1.1.1.3]
  P node: 1.1.1.1 dist: 1
  P node: 1.1.1.4 dist: 2
  P node: 1.1.1.5 dist: 2
  P node: 1.1.1.6 dist: 1
  Q node: 1.1.1.4 dist: 2
  Q node: 1.1.1.5 dist: 2
  Q node: 1.1.1.7 dist: 2
    PQ-node: 1.1.1.5
    Backup out-interface: eth3
 
Vertex [1.1.1.4]
  P node: 1.1.1.1 dist: 1
  P node: 1.1.1.4 dist: 2
  P node: 1.1.1.5 dist: 2
  P node: 1.1.1.6 dist: 1
  Q node: 1.1.1.4 dist: 2
  Q node: 1.1.1.5 dist: 2
  Q node: 1.1.1.7 dist: 2
    PQ-node: 1.1.1.5
    Backup out-interface: eth3
 
Vertex [1.1.1.5]
  P node: 1.1.1.1 dist: 1
  P node: 1.1.1.4 dist: 2
  P node: 1.1.1.5 dist: 2
  P node: 1.1.1.7 dist: 2
  P node: 1.1.1.3 dist: 1
  Q node: 1.1.1.4 dist: 2
  Q node: 1.1.1.5 dist: 2
    PQ-node: 1.1.1.4
    Backup out-interface: eth2
 
Vertex [1.1.1.6]
  P node: 1.1.1.1 dist: 1
  P node: 1.1.1.4 dist: 2
  P node: 1.1.1.5 dist: 2
  P node: 1.1.1.7 dist: 2
  P node: 1.1.1.3 dist: 1
  Q node: 1.1.1.4 dist: 2
  Q node: 1.1.1.5 dist: 2
    PQ-node: 1.1.1.4
    Backup out-interface: eth2
 
Vertex [1.1.1.7]
  P node: 1.1.1.1 dist: 1
  P node: 1.1.1.4 dist: 2
  P node: 1.1.1.5 dist: 2
  P node: 1.1.1.6 dist: 1
  Q node: 1.1.1.4 dist: 2
  Q node: 1.1.1.5 dist: 2
  Q node: 1.1.1.7 dist: 2
    PQ-node: 1.1.1.5
    Backup out-interface: eth3
 
P1#
P1#show ip ospf tilfa-repair-list
 
1.1.1.1/32
   Primary Path Metric   :2
   Primary Path Nexthop   : 10.1.2.1, eth1
   Route ftnix:1 ilmix:1
   SR Incoming Label   : 16001
   SR outgoing Label   : 3
   NO PQ node
 
1.1.1.2/32
1.1.1.3/32
   Primary Path Metric   :2
   Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix:2 ilmix:4
   SR Incoming Label   : 16003
   SR outgoing Label   : 3
   PQ-node: 1.1.1.5
 
   Backup ftnix:8 ilmix:9
   Backup outgoing Label   : 16003
   Bypass_trunk id :101
   Backup out interface: eth3
 
1.1.1.4/32
   Primary Path Metric   :3
   Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix:3 ilmix:5
   SR Incoming Label   : 16004
   SR outgoing Label   : 16004
   PQ-node: 1.1.1.5
 
   Backup ftnix:9 ilmix:10
   Backup outgoing Label   : 16004
   Bypass_trunk id :101
   Backup out interface: eth3
 
   Bypass-Trunk: 102 Name: 1.1.1.4_nexthop__10006 ftn_ix:7
   ftn_info->trunk_ftn_ix   : 7
   Number Of outgoing label 1:
    16004
   Nexthop address: 10.2.3.2
 
1.1.1.5/32
   Primary Path Metric   :3
   Primary Path Nexthop   : 10.2.6.2, eth3
   Route ftnix:4 ilmix:6
   SR Incoming Label   : 16005
   SR outgoing Label   : 16005
   PQ-node: 1.1.1.4
 
   Backup ftnix:10 ilmix:11
   Backup outgoing Label   : 16005
   Bypass_trunk id :102
   Backup out interface: eth2
 
   Bypass-Trunk: 101 Name: 1.1.1.5_nexthop__10007 ftn_ix:6
   ftn_info->trunk_ftn_ix   : 6
   Number Of outgoing label 1:
    16005
   Nexthop address: 10.2.6.2
 
1.1.1.6/32
   Primary Path Metric   :2
   Primary Path Nexthop   : 10.2.6.2, eth3
   Route ftnix:5 ilmix:8
   SR Incoming Label   : 16006
   SR outgoing Label   : 3
   PQ-node: 1.1.1.4
 
   Backup ftnix:11 ilmix:12
   Backup outgoing Label   : 16006
   Bypass_trunk id :102
   Backup out interface: eth2
 
1.1.1.7/32
   Primary Path Metric   :3
   Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix:12 ilmix:15
   SR Incoming Label   : 16007
   SR outgoing Label   : 16007
   PQ-node: 1.1.1.5
 
   Backup ftnix:14 ilmix:16
   Backup outgoing Label   : 16007
   Bypass_trunk id :101
   Backup out interface: eth3
 
10.1.2.0/24
10.2.3.0/24
10.2.6.0/24
10.3.4.0/24
10.3.7.0/24
10.4.5.0/24
10.5.6.0/24
P1#
 
P1#show mpls ilm-table
Codes: > - installed ILM, * - selected ILM, p - stale ILM
        K - CLI ILM, T - MPLS-TP, s - Stitched ILM
       S - SNMP, L - LDP, R - RSVP, C - CRLDP
       B - BGP , K - CLI , V - LDP_VC, I - IGP_SHORTCUT
       O - OSPF/OSPF6 SR, i - ISIS SR, k - SR CLI
       P - SR Policy, U - unknown
 
Code    FEC/VRF/L2CKT    ILM-ID      In-Label    Out-Label   In-Intf    Out-Intf/VRF       Nexthop                   LSP-Type
   O>   1.1.1.4/32         5           16004       16004       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.4/32         18          16004       16004       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   1.1.1.3/32         3           16003       3           N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.3/32         17          16003       16003       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   1.1.1.1/32         1           16001       3           N/A        eth1              10.1.2.1                  LSP_DEFAULT
   O>   10.1.2.1/32        2           24320       3           N/A        eth1              10.1.2.1                  LSP_DEFAULT
   O>   1.1.1.6/32         7           16006       3           N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   1.1.1.6/32         20          16006       16006       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.5/32         6           16005       16005       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   1.1.1.5/32         19          16005       16005       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.7/32         15          16007       16007       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.7/32         21          16007       16007       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   10.2.3.2/32        4           24321       3           N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   10.2.3.2/32        22          24321       16003       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   10.2.6.2/32        8           24322       3           N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   10.2.6.2/32        23          24322       16006       N/A        eth2              10.2.3.2                  LSP_DEFAULT
 
P1#show mpls forwarding-table
Codes: > - installed FTN, * - selected FTN, p - stale FTN,
       B - BGP FTN, K - CLI FTN, t - tunnel, P - SR Policy FTN,
       L - LDP FTN, R - RSVP-TE FTN, S - SNMP FTN, I - IGP-Shortcut,
       U - unknown FTN, O - SR-OSPF FTN, i - SR-ISIS FTN, k - SR-CLI FTN
 
Code    FEC                 FTN-ID    Nhlfe-ID  Tunnel-id   Pri   LSP-Type     Out-Label    Out-Intf    ELC   Nexthop
   O>   1.1.1.1/32          1         2         0           Yes   LSP_DEFAULT  3            eth1         No    10.1.2.1
   O>   1.1.1.3/32          2         4         0           Yes   LSP_DEFAULT  3            eth2         No    10.2.3.2
   O>   1.1.1.3/32          8         14        0           No    LSP_DEFAULT  16003        -           No    10.2.6.2
   O>   1.1.1.4/32          3         6         0           Yes   LSP_DEFAULT  16004        eth2         No    10.2.3.2
   O>   1.1.1.4/32          9         16        0           No    LSP_DEFAULT  16004        -           No    10.2.6.2
   O>   1.1.1.4/32          7         12        102         Yes   LSP_DEFAULT  16004        eth2         No    10.2.3.2
   O>   1.1.1.5/32          4         8         0           Yes   LSP_DEFAULT  16005        eth3         No    10.2.6.2
   O>   1.1.1.5/32          10        18        0           No    LSP_DEFAULT  16005        -           No    10.2.3.2
   O>   1.1.1.5/32          6         7         101         Yes   LSP_DEFAULT  16005        eth3         No    10.2.6.2
   O>   1.1.1.6/32          5         10        0           Yes   LSP_DEFAULT  3            eth3         No    10.2.6.2
   O>   1.1.1.6/32          11        20        0           No    LSP_DEFAULT  16006        -           No    10.2.3.2
   O>   1.1.1.7/32          12        22        0           Yes   LSP_DEFAULT  16007        eth2         No    10.2.3.2
   O>   1.1.1.7/32          14        24        0           No    LSP_DEFAULT  16007        -           No    10.2.6.2
   K>   202.1.1.0/24        13        -         -           -     LSP_DEFAULT  -            eth2         No    1.1.1.7
P1#
TI-LFA FRR Path using a PQ node with ISIS-SR
PE1
 
| PE1#configure terminal | Enter configure mode. | 
| PE1(config)#interface lo | Enter interface mode. | 
| PE1(config-if)#ip address 1.1.1.1/32 secondary | Configure the IP address of the interface. | 
| PE1(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| PE1(config-if)#prefix-sid index 1 | Configure prefix SID index value. | 
| PE1(config-if)#exit | Exit interface mode. | 
| PE1(config)#interface eth1 | Enter interface mode. | 
| PE1(config-if)#ip address 10.1.2.1/32 secondary | Configure the IP address of the interface. | 
| PE1(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| PE1(config-if)#label-switching | Enable label switching. | 
| PE1(config)#router isis 1 | Set the routing process ID. | 
| PE1(config-router)#metric-style wide | Configure metric style as wide. | 
| PE1(config-router)#net 49.0000.0000.0000.0001.00 | Configure network entity title (NET). | 
| PE1(config-router)#mpls traffic-eng router-id 1.1.1.1 | Enable MPLS Traffic Engineering under router process. | 
| PE1(config-router)#mpls traffic-eng level-1 | Enable MPLS Traffic Engineering as level-1 | 
| PE1(config-router)#mpls traffic-eng level-2 | Enable MPLS Traffic Engineering as level-2 | 
| PE1(config-router)#segment-routing mpls | Enable segment routing under router ISIS process. | 
| PE1(config-router)#exit | Exit router mode. | 
| PE1(config)#exit | Exit configure mode | 
P1
 
| P1#configure terminal | Enter configure mode. | 
| P1(config)#interface lo | Enter interface mode. | 
| P1(config-if)#ip address 1.1.1.2/32 secondary | Configure the IP address of the interface. | 
| P1(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| P1(config-if)#prefix-sid index 2 | Configure prefix SID index value. | 
| P1(config-if)#exit | Exit interface mode. | 
| P1(config)#interface eth1 | Enter interface mode. | 
| P1(config-if)#ip address 10.1.2.2/32 secondary | Configure the IP address of the interface. | 
| P1(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| P1(config-if)#label-switching | Enable label switching. | 
| P1(config-if)#exit | Exit interface mode. | 
| P1(config)#interface eth2 | Enter interface mode. | 
| P1(config-if)#ip address 10.2.3.1/32 secondary | Configure the IP address of the interface. | 
| P1(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| P1(config-if)#label-switching | Enable label switching. | 
| P1(config-if)#exit | Exit interface mode. | 
| P1(config)#interface eth3 | Enter interface mode. | 
| P1(config-if)#ip address 10.2.6.1/32 secondary | Configure the IP address of the interface. | 
| P1(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| P1(config-if)#label-switching | Enable label switching. | 
| P1(config-if)#exit | Exit interface mode. | 
| P1(config)#router isis 1 | Set the routing process ID . | 
| P1(config-router)#metric-style wide | Configure metric style as wide. | 
| P1(config-router)#net 49.0000.0000.0000.0002.00 | Configure Network entity title (NET). | 
| P1(config-router)#mpls traffic-eng router-id 1.1.1.2 | Enable MPLS Traffic Engineering under router process. | 
| P1(config-router)#mpls traffic-eng level-1 | Enable MPLS Traffic Engineering as level-1. | 
| P1(config-router)#mpls traffic-eng level-2 | Enable MPLS Traffic Engineering as level-2. | 
| P1(config-router)#capability cspf | Enable cspf capability under ISIS 1 process. | 
| P1(config-router)#segment-routing mpls | Enable segment routing under router process. | 
| P1(config-router)# fast-reroute ti-lfa level-1 proto ipv4 | Enable per-prefix TI-LFA FRR computation for ISIS level-1  | 
| P1(config-router)#exit | Exit router mode. | 
| P1(config)#exit | Exit configure mode | 
P2
 
| P2#configure terminal | Enter configure mode. | 
| P2(config)#interface lo | Enter interface mode. | 
| P2(config-if)#ip address 1.1.1.3/32 secondary | Configure the IP address of the interface. | 
| P2(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| P2(config-if)#prefix-sid index 3 | Configure prefix SID index value. | 
| P2(config-if)#exit | Exit interface mode. | 
| P2(config)#interface eth1 | Enter interface mode. | 
| P2(config-if)#ip address 10.3.4.1/32 secondary | Configure the IP address of the interface. | 
| P2(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| P2(config-if)#label-switching | Enable label switching. | 
| P2(config-if)#exit | Exit interface mode. | 
| P2(config)#interface eth2 | Enter interface mode. | 
| P2(config-if)#ip address 10.2.3.2/32 secondary | Configure the IP address of the interface. | 
| P2(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| P2(config-if)#label-switching | Enable label switching. | 
| P2(config-if)#exit | Exit interface mode. | 
| P2(config)#interface eth3 | Enter interface mode. | 
| P2(config-if)#ip address 10.3.7.1/32 secondary | Configure the IP address of the interface. | 
| P2(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| P2(config-if)#label-switching | Enable label switching. | 
| P2(config-if)#exit | Exit interface mode. | 
| P2(config)#router isis 1 | Set the routing process ID . | 
| P2(config-router)#metric-style wide | Configure metric style as wide. | 
| P2(config-router)#net 49.0000.0000.0000.0003.00 | Configure Network entity title (NET). | 
| P2(config-router)#mpls traffic-eng router-id 1.1.1.3 | Enable MPLS Traffic Engineering under router process. | 
| P2(config-router)#mpls traffic-eng level-1 | Enable MPLS Traffic Engineering as level-1. | 
| P2(config-router)#mpls traffic-eng level-2 | Enable MPLS Traffic Engineering as level-2 | 
| P2(config)#router isis 1 | Set the routing process ID . | 
| P2(config-router)#metric-style wide | Configure metric style as wide. | 
| P2(config-router)#net 49.0001.0000.0000.0003.00 | Configure Network entity title (NET). | 
| P2(config-router)#segment-routing mpls | Enable segment routing under router process. | 
| P2(config-router)#exit | Exit router mode. | 
P3
 
| P3#configure terminal | Enter configure mode. | 
| P3(config)#interface lo | Enter interface mode. | 
| P3(config-if)#ip address 1.1.1.4/32 secondary | Configure the IP address of the interface. | 
| P3(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| P3(config-if)#prefix-sid index 4 | Configure prefix SID index value. | 
| P3(config-if)#exit | Exit interface mode. | 
| P3(config)#interface eth1 | Enter interface mode. | 
| P3(config-if)#ip address 10.3.4.2/32 secondary | Configure the IP address of the interface. | 
| P3(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| P3(config-if)#label-switching | Enable label switching. | 
| P3(config-if)#exit | Exit interface mode. | 
| P3(config)#interface eth2 | Enter interface mode. | 
| P3(config-if)ip address 10.4.5.1/32 secondary | Configure the IP address of the interface. | 
| P3(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| P3(config-if)#label-switching | Enable label switching. | 
| P3(config-if)#exit | Exit interface mode. | 
| P3(config)#router isis 1 | Set the routing process ID . | 
| P3(config-router)#metric-style wide | Configure metric style as wide. | 
| P3(config-router)#net 49.0000.0000.0000.0004.00 | Configure Network entity title (NET). | 
| P3(config-router)#mpls traffic-eng router-id 1.1.1.4 | Enable MPLS Traffic Engineering under router process. | 
| P3(config-router)#mpls traffic-eng level-1 | Enable MPLS Traffic Engineering as level-1. | 
| P3(config-router)#mpls traffic-eng level-2 | Enable MPLS Traffic Engineering as level-2. | 
| P3(config-router)#exit | Exit router isis mode | 
| P3(config)#router isis 1 | Set the routing process ID . | 
| P3(config-router)#metric-style wide | Configure metric style as wide. | 
| P3(config-router)#net 49.0000.0000.0000.0004.00 | Configure Network entity title (NET). | 
| P3(config-router)#segment-routing mpls | Enable segment routing under router process. | 
| P3(config-router)#exit | Exit router mode. | 
P4
 
| P4#configure terminal | Enter configure mode. | 
| P4(config)#interface lo | Enter interface mode. | 
| P4(config-if)#ip address 1.1.1.5/32 | Configure the IP address of the interface. | 
| P4(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| P4(config-if)#prefix-sid index 5 | Configure prefix SID index value. | 
| P4(config-if)#exit | Exit interface mode. | 
| P4(config)#interface eth1 | Enter interface mode. | 
| P4(config-if)#ip address 10.5.6.1/32 secondary | Configure the IP address of the interface. | 
| P4(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| P4(config-if)#label-switching | Enable label switching. | 
| P4(config-if)#exit | Exit interface mode. | 
| P4(config)#interface eth2 | Enter interface mode. | 
| P4(config-if)#ip address 10.4.5.2/32 secondary | Configure the IP address of the interface. | 
| P4(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| P4(config-if)#label-switching | Enable label switching. | 
| P4(config-if)#exit | Exit interface mode. | 
| P4(config)#router isis 1 | Set the routing process ID . | 
| P4(config-router)#metric-style wide | Configure metric style as wide. | 
| P4(config-router)#net 49.0000.0000.0000.0005.00 | Configure Network entity title (NET). | 
| P4(config-router)#mpls traffic-eng router-id 1.1.1.5 | Enable MPLS Traffic Engineering under router process. | 
| P4(config-router)#mpls traffic-eng level-1 | Enable MPLS Traffic Engineering as level-1. | 
| P4(config-router)#mpls traffic-eng level-2 | Enable MPLS Traffic Engineering as level-2. | 
| P4(config-router)#segment-routing mpls | Enable segment routing under router process. | 
| P4(config-router)#exit | Exit router mode. | 
	P5
 
| P5#configure terminal | Enter configure mode. | 
| P5(config)#interface lo | Enter interface mode. | 
| P5(config-if)#ip address 1.1.1.6/32 secondary | Configure the IP address of the interface. | 
| P5(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| P5(config-if)#prefix-sid index 6 | Configure prefix SID index value. | 
| P5(config-if)#exit | Exit interface mode. | 
| P5(config)#interface eth1 | Enter interface mode. | 
| P5(config-if)#ip address 10.5.6.2/32 secondary | Configure the IP address of the interface. | 
| P5(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| P5(config-if)#label-switching | Enable label switching. | 
| P5(config-if)#exit | Exit interface mode. | 
| P5(config)#interface eth3 | Enter interface mode. | 
| P5(config-if)#ip address 10.2.6.2/32 secondary | Configure the IP address of the interface. | 
| P5(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| P5(config-if)#label-switching | Enable label switching. | 
| P5(config-if)#exit | Exit interface mode. | 
| P5(config)#router isis 1 | Set the routing process ID . | 
| P5(config-router)#metric-style wide | Configure metric style as wide. | 
| P5(config-router)#net 49.0000.0000.0000.0006.00 | Configure Network entity title (NET). | 
| P5(config-router)#mpls traffic-eng router-id 1.1.1.6 | Enable MPLS Traffic Engineering under router process. | 
| P5(config-router)#mpls traffic-eng level-1 | Enable MPLS Traffic Engineering as level-1. | 
| P5(config-router)#mpls traffic-eng level-2 | Enable MPLS Traffic Engineering as level-2. | 
| P5(config-router)#segment-routing mpls | Enable segment routing under router process. | 
| P5(config-router)#exit | Exit router mode. | 
| P5(config)#commit | Commit the candidate configuration to the running configuration. | 
PE2
 
| PE2#configure terminal | Enter configure mode. | 
| PE2(config)#interface lo | Enter interface mode. | 
| PE2(config-if)#ip address 1.1.1.7/32 secondary | Configure the IP address of the interface. | 
| PE2(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| PE2(config-if)#prefix-sid index 7 | Configure prefix SID index value. | 
| PE2(config-if)#exit | Exit interface mode. | 
| PE2(config)#interface eth3 | Enter interface mode. | 
| PE2(config-if)#ip address 10.3.7.2/32 secondary | Configure the IP address of the interface. | 
| PE2(config-if)#ip router isis 1 | Make the interface part of the router ISIS 1 instance. | 
| PE2(config-if)#label-switching | Enable label switching. | 
| PE2(config-if)#exit | Exit interface mode. | 
| PE2(config)#router isis 1 | Set the routing process ID . | 
| PE2(config-router)#metric-style wide | Configure metric style as wide. | 
| PE2(config-router)#net 49.0000.0000.0000.0007.00 | Configure Network entity title (NET). | 
| PE2(config-router)#mpls traffic-eng router-id 1.1.1.7 | Enable MPLS Traffic Engineering under router process. | 
| PE2(config-router)#mpls traffic-eng level-1 | Enable MPLS Traffic Engineering as level-1. | 
| PE2(config-router)#mpls traffic-eng level-2 | Enable MPLS Traffic Engineering as level-2. | 
| PE2(config-router)#segment-routing mpls | Enable segment routing under router process. | 
| PE2(config-router)#exit | Exit router mode. | 
| PE2(config)#commit | Commit the candidate configuration to the running configuration. | 
Validation 1
P1
P1#show clns neighbors
 
Total number of L1 adjacencies: 3
Total number of L2 adjacencies: 3
Total number of adjacencies: 6
Tag 1:  VRF : default
System Id      Interface   SNPA                State  Holdtime  Type Protocol
0000.0000.0003 eth2         3c2c.99c9.097f      Up     7         L1   IS-IS
                                                Up     7         L2   IS-IS
0000.0000.0006 eth3         3c2c.992c.ec83      Up     6         L1   IS-IS
                                                Up     6         L2   IS-IS
0000.0000.0001 eth1         04f8.f824.d009      Up     19        L1   IS-IS
                                                Up     19        L2   IS-IS
Validation 2
P1
P1#show isis tilfa pq
 
IS-IS Level-1 Link State Database:
 
Node: 0000.0000.0001.00-00
  P node: 0000.0000.0004.00-00 primary dist:20
  P node: 0000.0000.0005.00-00 primary dist:20
  P node: 0000.0000.0007.00-00 primary dist:20
  P node: 0000.0000.0003.00-00 primary dist:10
  P node: 0000.0000.0006.00-00 primary dist:10
  No PQ Node found on backup path
 
Node: 0000.0000.0003.00-00
  P node: 0000.0000.0004.00-00 primary dist:20
  P node: 0000.0000.0005.00-00 primary dist:20
  P node: 0000.0000.0006.00-00 primary dist:10
  P node: 0000.0000.0001.00-00 primary dist:10
  Q node: 0000.0000.0004.00-00 primary dist:20
  Q node: 0000.0000.0005.00-00 primary dist:20
  Q node: 0000.0000.0007.00-00 primary dist:20
  PQ Node: 0000.0000.0005.00-00 backup dist:20
 
Node: 0000.0000.0004.00-00
  P node: 0000.0000.0004.00-00 primary dist:20
  P node: 0000.0000.0005.00-00 primary dist:20
  P node: 0000.0000.0006.00-00 primary dist:10
  P node: 0000.0000.0001.00-00 primary dist:10
  Q node: 0000.0000.0004.00-00 primary dist:20
  Q node: 0000.0000.0005.00-00 primary dist:20
  Q node: 0000.0000.0007.00-00 primary dist:20
  PQ Node: 0000.0000.0005.00-00 backup dist:20
 
Node: 0000.0000.0005.00-00
  P node: 0000.0000.0004.00-00 primary dist:20
  P node: 0000.0000.0005.00-00 primary dist:20
  P node: 0000.0000.0007.00-00 primary dist:20
  P node: 0000.0000.0003.00-00 primary dist:10
  P node: 0000.0000.0001.00-00 primary dist:10
  Q node: 0000.0000.0004.00-00 primary dist:20
  Q node: 0000.0000.0005.00-00 primary dist:20
  PQ Node: 0000.0000.0004.00-00 backup dist:20
 
Node: 0000.0000.0006.00-00
  P node: 0000.0000.0004.00-00 primary dist:20
  P node: 0000.0000.0005.00-00 primary dist:20
  P node: 0000.0000.0007.00-00 primary dist:20
  P node: 0000.0000.0003.00-00 primary dist:10
  P node: 0000.0000.0001.00-00 primary dist:10
  Q node: 0000.0000.0004.00-00 primary dist:20
  Q node: 0000.0000.0005.00-00 primary dist:20
  PQ Node: 0000.0000.0004.00-00 backup dist:20
 
Node: 0000.0000.0007.00-00
  P node: 0000.0000.0004.00-00 primary dist:20
  P node: 0000.0000.0005.00-00 primary dist:20
  P node: 0000.0000.0006.00-00 primary dist:10
  P node: 0000.0000.0001.00-00 primary dist:10
  Q node: 0000.0000.0004.00-00 primary dist:20
  Q node: 0000.0000.0005.00-00 primary dist:20
  Q node: 0000.0000.0007.00-00 primary dist:20
  PQ Node: 0000.0000.0005.00-00 backup dist:20
 
P1#show ip isis route tilfa
 
Tag   : 1  VRF : default
Codes : L1 - IS-IS level-1, L2 - IS-IS level-2,
        C - Connected Routes, ia - IS-IS inter area
 
1.1.1.1/32
 L1: Primary Path Nexthop   : 10.1.2.1, eth1
   Route ftnix :1  ilmix :5
   SR Incoming Label   : 16001
   SR outgoing Label   : 3
   NO PQ node
   NO Backup
 
 
1.1.1.2/32
 C: Primary Path Nexthop   : 0.0.0.0, lo
   Route ftnix :0  ilmix :1
   SR Incoming Label   : 16002
   No SR outgoing Label
   NO PQ node
   NO Backup
 
 
1.1.1.3/32
 L1: Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix :2  ilmix :6
   SR Incoming Label   : 16003
   SR outgoing Label   : 3
   PQ node : 1.1.1.5
   Backup ftnix :10   ilmix :47
   Backup outgoing Label   : 16003
   Bypass_trunk id :2201
   Backup out interface : eth3
 
 
1.1.1.4/32
 L1: Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix :3  ilmix :7
   SR Incoming Label   : 16004
   SR outgoing Label   : 16004
   PQ node : 1.1.1.5
   Backup ftnix :11   ilmix :48
   Backup outgoing Label   : 16004
   Bypass_trunk id :2201
   Backup out interface : eth3
 
   Trunk : 2202 :1.1.1.4_nh_10006   ftn_ix : 9 ref_cnt:3
   Number Of outgoing label : 1
    16004
   Nexthop address : 10.2.3.2
 
 
1.1.1.5/32
 L1: Primary Path Nexthop   : 10.2.6.2, eth3
   Route ftnix :4  ilmix :8
   SR Incoming Label   : 16005
   SR outgoing Label   : 16005
   PQ node : 1.1.1.4
   Backup ftnix :12   ilmix :49
   Backup outgoing Label   : 16005
   Bypass_trunk id :2202
   Backup out interface : eth2
 
   Trunk : 2201 :1.1.1.5_nh_10007   ftn_ix : 8 ref_cnt:4
   Number Of outgoing label : 1
    16005
   Nexthop address : 10.2.6.2
 
 
1.1.1.6/32
 L1: Primary Path Nexthop   : 10.2.6.2, eth3
   Route ftnix :5  ilmix :15
   SR Incoming Label   : 16006
   SR outgoing Label   : 3
   PQ node : 1.1.1.4
   Backup ftnix :13   ilmix :50
   Backup outgoing Label   : 16006
   Bypass_trunk id :2202
   Backup out interface : eth2
 
 
1.1.1.7/32
 L1: Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix :6  ilmix :40
   SR Incoming Label   : 16007
   SR outgoing Label   : 16007
   PQ node : 1.1.1.5
   Backup ftnix :14   ilmix :53
   Backup outgoing Label   : 16007
   Bypass_trunk id :2201
   Backup out interface : eth3
 
P1#
 
P1#show mpls ilm-table
Codes: > - installed ILM, * - selected ILM, p - stale ILM
        K - CLI ILM, T - MPLS-TP, s - Stitched ILM
       S - SNMP, L - LDP, R - RSVP, C - CRLDP
       B - BGP , K - CLI , V - LDP_VC, I - IGP_SHORTCUT
       O - OSPF/OSPF6 SR, i - ISIS SR, k - SR CLI
       P - SR Policy, U - unknown
 
Code    FEC/VRF/L2CKT    ILM-ID      In-Label    Out-Label   In-Intf    Out-Intf/VRF       Nexthop                   LSP-Type
   i>   10.1.2.1/32        2           24960       3           N/A        eth1              10.1.2.1                  LSP_DEFAULT
   i>   1.1.1.4/32         7           16004       16004       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   1.1.1.4/32         48          16004       16004       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   1.1.1.2/32         1           16002       Nolabel     N/A        N/A              127.0.0.1                 LSP_DEFAULT
   i>   1.1.1.1/32         5           16001       3           N/A        eth1              10.1.2.1                  LSP_DEFAULT
   i>   1.1.1.3/32         6           16003       3           N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   1.1.1.3/32         47          16003       16003       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   1.1.1.6/32         15          16006       3           N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   1.1.1.6/32         50          16006       16006       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   1.1.1.5/32         8           16005       16005       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   1.1.1.5/32         49          16005       16005       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   1.1.1.7/32         40          16007       16007       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   1.1.1.7/32         53          16007       16007       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   10.2.3.2/32        3           24961       3           N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   10.2.3.2/32        51          24961       16003       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   10.2.6.2/32        4           24962       3           N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   10.2.6.2/32        52          24962       16006       N/A        eth2              10.2.3.2                  LSP_DEFAULT
P1#
 
P1#show mpls forwarding-table
Codes: > - installed FTN, * - selected FTN, p - stale FTN,
       B - BGP FTN, K - CLI FTN, t - tunnel, P - SR Policy FTN,
       L - LDP FTN, R - RSVP-TE FTN, S - SNMP FTN, I - IGP-Shortcut,
       U - unknown FTN, O - SR-OSPF FTN, i - SR-ISIS FTN, k - SR-CLI FTN
 
Code    FEC                 FTN-ID    Nhlfe-ID  Tunnel-id   Pri   LSP-Type     Out-Label    Out-Intf    ELC   Nexthop
   i>   1.1.1.1/32          1         5         0           Yes   LSP_DEFAULT  3            eth1         No    10.1.2.1
   i>   1.1.1.3/32          2         3         0           Yes   LSP_DEFAULT  3            eth2         No    10.2.3.2
   i>   1.1.1.3/32          10        15        0           No    LSP_DEFAULT  16003        -           No    10.2.6.2
   i>   1.1.1.4/32          3         7         0           Yes   LSP_DEFAULT  16004        eth2         No    10.2.3.2
   i>   1.1.1.4/32          11        20        0           No    LSP_DEFAULT  16004        -           No    10.2.6.2
   i>   1.1.1.4/32          9         13        2202        Yes   LSP_DEFAULT  16004        eth2         No    10.2.3.2
   i>   1.1.1.5/32          4         8         0           Yes   LSP_DEFAULT  16005        eth3         No    10.2.6.2
   i>   1.1.1.5/32          12        21        0           No    LSP_DEFAULT  16005        -           No    10.2.3.2
   i>   1.1.1.5/32          8         12        2201        Yes   LSP_DEFAULT  16005        eth3         No    10.2.6.2
   i>   1.1.1.6/32          5         10        0           Yes   LSP_DEFAULT  3            eth3         No    10.2.6.2
   i>   1.1.1.6/32          13        22        0           No    LSP_DEFAULT  16006        -           No    10.2.3.2
   i>   1.1.1.7/32          6         11        0           Yes   LSP_DEFAULT  16007        eth2         No    10.2.3.2
   i>   1.1.1.7/32          14        24        0           No    LSP_DEFAULT  16007        -           No    10.2.6.2
   K>   202.1.1.0/24        7         -         -           -     LSP_DEFAULT  -            eth2         No    1.1.1.7
P1#
 
P1#show mpls ftn-table 1.1.1.4/32
 Primary FTN entry with FEC: 1.1.1.4/32, id: 3, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to LSP, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, Description: N/A, Color: 0
     Cross connect ix: 3, in intf: - in label: 0 out-segment ix: 6
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 6, owner: ISIS-SR, Stale: NO, out intf: eth2, out label: 16004
    Nexthop addr: 10.2.3.2        cross connect ix: 3, op code: Push
 
 
 Non-primary FTN entry with FEC: 1.1.1.4/32, id: 11, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 10, in intf: - in label: 0 out-segment ix: 18
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 18, owner: ISIS-SR, Stale: NO, ISIS-SR out intf: eth3, transport out intf: N/A, out label: 16004
    Nexthop addr: 10.2.6.2        cross connect ix: 10, op code: Push and Lookup
 
  bypass_ftn_ix 8
 
 Primary FTN entry with FEC: 1.1.1.4/32, id: 9, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 2202, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 3, in intf: - in label: 0 out-segment ix: 6
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 6, owner: ISIS-SR, Stale: NO, out intf: eth2, out label: 16004
    Nexthop addr: 10.2.3.2        cross connect ix: 3, op code: Push
P1#
 
P1#show mpls ftn-table 1.1.1.5/32
 Primary FTN entry with FEC: 1.1.1.5/32, id: 4, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to LSP, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, Description: N/A, Color: 0
     Cross connect ix: 7, in intf: - in label: 0 out-segment ix: 16
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 16, owner: OSPF-SR, Stale: NO, out intf: eth3, out label: 16005
    Nexthop addr: 10.2.6.2        cross connect ix: 7, op code: Push
 
 
 Non-primary FTN entry with FEC: 1.1.1.5/32, id: 12, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 8, in intf: - in label: 0 out-segment ix: 17
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 17, owner: OSPF-SR, Stale: NO, OSPF-SR out intf: eth2, transport out intf: N/A, out label: 16005
    Nexthop addr: 10.2.3.2        cross connect ix: 8, op code: Push and Lookup
 
  bypass_ftn_ix 9
 
 Primary FTN entry with FEC: 1.1.1.5/32, id: 8, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 2201, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 7, in intf: - in label: 0 out-segment ix: 16
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 16, owner: OSPF-SR, Stale: NO, out intf: eth3, out label: 16005
    Nexthop addr: 10.2.6.2        cross connect ix: 7, op code: Push
 
 
P1#
 
P1#show mpls ftn-table 1.1.1.7/32
 Primary FTN entry with FEC: 1.1.1.7/32, id: 6, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to LSP, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, Description: N/A, Color: 0
     Cross connect ix: 4, in intf: - in label: 0 out-segment ix: 4
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 4, owner: ISIS-SR, Stale: NO, out intf: eth2, out label: 16007
    Nexthop addr: 10.2.3.2        cross connect ix: 4, op code: Push
 
 
 Non-primary FTN entry with FEC: 1.1.1.7/32, id: 14, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 11, in intf: - in label: 0 out-segment ix: 23
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 23, owner: ISIS-SR, Stale: NO, ISIS-SR out intf: eth3, transport out intf: N/A, out label: 16007
    Nexthop addr: 10.2.6.2        cross connect ix: 11, op code: Push and Lookup
 
  bypass_ftn_ix 8
 
P1#
 
 
Topology
 
TI-LFA FRR path using a PQ Node that is a Direct Neighbor
TI-LFA FRR Path using a Direct Neighbor with OSPF-SR
P1
 
| P1#configure terminal | Enter configure mode. | 
| P1(config)#interface eth3 | Enter interface mode. | 
| P1(config-if)#ip ospf cost 1000 | Configure the OSPF cost for the interface  | 
| P1(config-if)#exit | Exit interface mode. | 
| P1(config)#exit | Exit configure mode | 
P5
 
| P5#configure terminal | Enter configure mode. | 
| P5(config)#interface eth3 | Enter interface mode. | 
| P5(config-if)#ip ospf cost 1000 | Configure the OSPF cost for the interface  | 
| P5(config-if)#exit | Exit interface mode. | 
| P5(config)#exit | Exit configure mode | 
Validation
P1
P1#show ip ospf tilfa-backup-path
OSPF process 100:
Route [1.1.1.1]
   NO PQ node
Route [1.1.1.2]
   NO PQ node
Route [1.1.1.3]
   PQ-node: 1.1.1.6
Route [1.1.1.4]
   PQ-node: 1.1.1.6
Route [1.1.1.5]
   PQ-node: 1.1.1.6
Route [1.1.1.6]
   PQ-node: 1.1.1.6
Route [1.1.1.7]
   PQ-node: 1.1.1.6
Route [10.1.2.0]
Route [10.2.3.0]
Route [10.2.6.0]
Route [10.3.4.0]
Route [10.3.7.0]
Route [10.4.5.0]
Route [10.5.6.0]
 Neighbor [1.1.1.1]
Neighbor [1.1.1.3]
   PQ-node: 1.1.1.6
Neighbor [1.1.1.6]
   PQ-node: 1.1.1.3
 
Displaying vertex-info in tilfa_network table
Vertex [1.1.1.1]
  P node: 1.1.1.4 dist: 2
  P node: 1.1.1.5 dist: 3
  P node: 1.1.1.6 dist: 4
  P node: 1.1.1.7 dist: 2
  P node: 1.1.1.3 dist: 1
  P node: 1.1.1.6 dist: 4
 
Vertex [1.1.1.2]
  No P Nodes
  No Q Nodes
 
Vertex [1.1.1.3]
  P node: 1.1.1.1 dist: 1
  P node: 1.1.1.3 dist: 1
  P node: 1.1.1.4 dist: 2
  P node: 1.1.1.5 dist: 3
  P node: 1.1.1.7 dist: 2
  P node: 1.1.1.6 dist: 4
  Q node: 1.1.1.4 dist: 2
  Q node: 1.1.1.5 dist: 3
  Q node: 1.1.1.6 dist: 4
  Q node: 1.1.1.7 dist: 2
    PQ-node: 1.1.1.6
    Backup out-interface: eth3
 
Vertex [1.1.1.4]
  P node: 1.1.1.1 dist: 1
  P node: 1.1.1.3 dist: 1
  P node: 1.1.1.4 dist: 2
  P node: 1.1.1.5 dist: 3
  P node: 1.1.1.7 dist: 2
  P node: 1.1.1.6 dist: 4
  Q node: 1.1.1.4 dist: 2
  Q node: 1.1.1.5 dist: 3
  Q node: 1.1.1.6 dist: 4
  Q node: 1.1.1.7 dist: 2
    PQ-node: 1.1.1.6
    Backup out-interface: eth3
 
Vertex [1.1.1.5]
  P node: 1.1.1.1 dist: 1
  P node: 1.1.1.3 dist: 1
  P node: 1.1.1.4 dist: 2
  P node: 1.1.1.5 dist: 3
  P node: 1.1.1.7 dist: 2
  P node: 1.1.1.6 dist: 4
  Q node: 1.1.1.4 dist: 2
  Q node: 1.1.1.5 dist: 3
  Q node: 1.1.1.6 dist: 4
  Q node: 1.1.1.7 dist: 2
    PQ-node: 1.1.1.6
    Backup out-interface: eth3
 
Vertex [1.1.1.6]
  P node: 1.1.1.1 dist: 1
  P node: 1.1.1.3 dist: 1
  P node: 1.1.1.4 dist: 2
  P node: 1.1.1.5 dist: 3
  P node: 1.1.1.7 dist: 2
  P node: 1.1.1.6 dist: 4
  Q node: 1.1.1.4 dist: 2
  Q node: 1.1.1.5 dist: 3
  Q node: 1.1.1.6 dist: 4
  Q node: 1.1.1.7 dist: 2
    PQ-node: 1.1.1.6
    Backup out-interface: eth3
 
Vertex [1.1.1.7]
  P node: 1.1.1.1 dist: 1
  P node: 1.1.1.3 dist: 1
  P node: 1.1.1.4 dist: 2
  P node: 1.1.1.5 dist: 3
  P node: 1.1.1.7 dist: 2
  P node: 1.1.1.6 dist: 4
  Q node: 1.1.1.4 dist: 2
  Q node: 1.1.1.5 dist: 3
  Q node: 1.1.1.6 dist: 4
  Q node: 1.1.1.7 dist: 2
    PQ-node: 1.1.1.6
    Backup out-interface: eth3
 
P1#show ip ospf tilfa-repair-list
 
1.1.1.1/32
   Primary Path Metric   :2
   Primary Path Nexthop   : 10.1.2.1, eth1
   Route ftnix:1 ilmix:1
   SR Incoming Label   : 16001
   SR outgoing Label   : 3
   NO PQ node
 
1.1.1.2/32
   Primary Path Metric   :1
   Primary Path Nexthop   : 1.1.1.2, lo
   Route ftnix:0 ilmix:0
   NO PQ node
 
1.1.1.3/32
   Primary Path Metric   :2
   Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix:2 ilmix:3
   SR Incoming Label   : 16003
   SR outgoing Label   : 3
   PQ-node: 1.1.1.6
 
   Backup ftnix:9 ilmix:24
   Backup outgoing Label   : 16003
   Bypass_trunk id :103
   Backup out interface: eth3
 
1.1.1.4/32
   Primary Path Metric   :3
   Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix:5 ilmix:8
   SR Incoming Label   : 16004
   SR outgoing Label   : 16004
   PQ-node: 1.1.1.6
 
   Backup ftnix:10 ilmix:38
   Backup outgoing Label   : 16004
   Bypass_trunk id :103
   Backup out interface: eth3
 
1.1.1.5/32
   Primary Path Metric   :4
   Primary Path Nexthop   : 10.2.3.2, eth3
   Route ftnix:6 ilmix:15
   SR Incoming Label   : 16005
   SR outgoing Label   : 16005
   PQ-node: 1.1.1.6
 
   Backup ftnix:11 ilmix:39
   Backup outgoing Label   : 16005
   Bypass_trunk id :103
   Backup out interface: eth2
 
1.1.1.6/32
   Primary Path Metric   :5
   Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix:3 ilmix:4
   SR Incoming Label   : 16006
   SR outgoing Label   : 16006
   PQ-node: 1.1.1.6
 
   Backup ftnix:12 ilmix:40
   Backup outgoing Label   : 3
   Bypass_trunk id :103
   Backup out interface: eth3
 
   Bypass-Trunk: 103 Name: 1.1.1.6_nexthop__10007 ftn_ix:14
   ftn_info->trunk_ftn_ix   : 14
   Number Of outgoing label 1:
    3
   Nexthop address: 10.2.6.2
 
1.1.1.7/32
   Primary Path Metric   :3
   Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix:4 ilmix:7
   SR Incoming Label   : 16007
   SR outgoing Label   : 16007
   PQ-node: 1.1.1.6
 
   Backup ftnix:13 ilmix:41
   Backup outgoing Label   : 16007
   Bypass_trunk id :103
   Backup out interface: eth3
 
10.1.2.0/24
10.2.3.0/24
10.2.6.0/24
10.3.4.0/24
10.3.7.0/24
10.4.5.0/24
10.5.6.0/24
P1#
 
P1#show mpls ilm-table
Codes: > - installed ILM, * - selected ILM, p - stale ILM
        K - CLI ILM, T - MPLS-TP, s - Stitched ILM
       S - SNMP, L - LDP, R - RSVP, C - CRLDP
       B - BGP , K - CLI , V - LDP_VC, I - IGP_SHORTCUT
       O - OSPF/OSPF6 SR, i - ISIS SR, k - SR CLI
       P - SR Policy, U - unknown
 
Code    FEC/VRF/L2CKT    ILM-ID      In-Label    Out-Label   In-Intf    Out-Intf/VRF       Nexthop                   LSP-Type
   O>   1.1.1.6/32         8           16006       16006       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.6/32         23          16006       3           N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   1.1.1.4/32         5           16004       16004       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.4/32         21          16004       16004       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   1.1.1.3/32         4           16003       3           N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.3/32         20          16003       16003       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   1.1.1.1/32         1           16001       3           N/A        eth1              10.1.2.1                  LSP_DEFAULT
   O>   1.1.1.5/32         6           16005       16005       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.5/32         22          16005       16005       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   10.1.2.1/32        2           24320       3           N/A        eth1              10.1.2.1                  LSP_DEFAULT
   O>   1.1.1.7/32         15          16007       16007       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.7/32         24          16007       16007       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   10.2.3.2/32        3           24321       3           N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   10.2.3.2/32        17          24321       16003       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   10.2.6.2/32        7           24322       3           N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   10.2.6.2/32        25          24322       3           N/A        eth2              10.2.3.2                  LSP_DEFAULT
P1#
P1#show mpls forwarding-table
Codes: > - installed FTN, * - selected FTN, p - stale FTN,
       B - BGP FTN, K - CLI FTN, t - tunnel, P - SR Policy FTN,
       L - LDP FTN, R - RSVP-TE FTN, S - SNMP FTN, I - IGP-Shortcut,
       U - unknown FTN, O - SR-OSPF FTN, i - SR-ISIS FTN, k - SR-CLI FTN
 
Code    FEC                 FTN-ID    Nhlfe-ID  Tunnel-id   Pri   LSP-Type     Out-Label    Out-Intf    ELC   Nexthop
   O>   1.1.1.1/32          1         2         0           Yes   LSP_DEFAULT  3            eth1         No    10.1.2.1
   O>   1.1.1.3/32          2         4         0           Yes   LSP_DEFAULT  3            eth2         No    10.2.3.2
   O>   1.1.1.3/32          8         11        0           No    LSP_DEFAULT  16003        -           No    10.2.6.2
   O>   1.1.1.3/32          6         7         101         Yes   LSP_DEFAULT  3            eth2         No    10.2.3.2
   O>   1.1.1.4/32          3         6         0           Yes   LSP_DEFAULT  16004        eth2         No    10.2.3.2
   O>   1.1.1.4/32          9         15        0           No    LSP_DEFAULT  16004        -           No    10.2.6.2
   O>   1.1.1.5/32          4         8         0           Yes   LSP_DEFAULT  16005        eth2         No    10.2.3.2
   O>   1.1.1.5/32          10        18        0           No    LSP_DEFAULT  16005        -           No    10.2.6.2
   O>   1.1.1.6/32          5         10        0           Yes   LSP_DEFAULT  16006        eth2         No    10.2.3.2
   O>   1.1.1.6/32          11        20        0           No    LSP_DEFAULT  3            eth3         No    10.2.6.2
   O>   1.1.1.6/32          15        25        103         Yes   LSP_DEFAULT  3            eth3         No    10.2.6.2
   O>   1.1.1.7/32          12        22        0           Yes   LSP_DEFAULT  16007        eth2         No    10.2.3.2
   O>   1.1.1.7/32          14        24        0           No    LSP_DEFAULT  16007        -           No    10.2.6.2
   K>   202.1.1.0/24        13        -         -           -     LSP_DEFAULT  -            eth2         No    1.1.1.7
P1#
 
P1#show mpls ftn-table 1.1.1.6/32
 Primary FTN entry with FEC: 1.1.1.6/32, id: 5, row status: Active, Tunnel-Policy: N/A
  Owner: OSPF-SR, distance: 110, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 9, in intf: - in label: 0 out-segment ix: 19
      Owner: OSPF-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 19, owner: OSPF-SR, Stale: NO, OSPF-SR out intf: eth2, transport out intf: N/A, out label: 16006
    Nexthop addr: 10.2.3.2        cross connect ix: 9, op code: Push and Lookup
 
 
 Non-primary FTN entry with FEC: 1.1.1.6/32, id: 11, row status: Active, Tunnel-Policy: N/A
  Owner: OSPF-SR, distance: 110, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 5, in intf: - in label: 0 out-segment ix: 9
      Owner: N/A, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 9, owner: N/A, Stale: NO, out intf: eth3, out label: 3
    Nexthop addr: 10.2.6.2        cross connect ix: 5, op code: Push
 
  bypass_ftn_ix 15
 
 Primary FTN entry with FEC: 1.1.1.6/32, id: 15, row status: Active, Tunnel-Policy: N/A
  Owner: OSPF-SR, distance: 110, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 103, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 5, in intf: - in label: 0 out-segment ix: 9
      Owner: N/A, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 9, owner: N/A, Stale: NO, out intf: eth3, out label: 3
    Nexthop addr: 10.2.6.2        cross connect ix: 5, op code: Push
 
 
P1#
 
 
P1#show mpls ftn-table 1.1.1.7/32
 Primary FTN entry with FEC: 1.1.1.7/32, id: 12, row status: Active, Tunnel-Policy: N/A
  Owner: OSPF-SR, distance: 110, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 10, in intf: - in label: 0 out-segment ix: 21
      Owner: OSPF-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 21, owner: OSPF-SR, Stale: NO, out intf: eth2, out label: 16007
    Nexthop addr: 10.2.3.2        cross connect ix: 10, op code: Push
 
 
 Non-primary FTN entry with FEC: 1.1.1.7/32, id: 14, row status: Active, Tunnel-Policy: N/A
  Owner: OSPF-SR, distance: 110, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 11, in intf: - in label: 0 out-segment ix: 23
      Owner: OSPF-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 23, owner: OSPF-SR, Stale: NO, OSPF-SR out intf: eth3, transport out intf: N/A, out label: 16007
    Nexthop addr: 10.2.6.2        cross connect ix: 11, op code: Push and Lookup
 
  bypass_ftn_ix 15
 
P1#
TI-LFA FRR Path using a Direct Neighbor with ISIS-SR
P1
 
| P1#configure terminal | Enter configure mode. | 
| P1(config)#interface eth3 | Enter interface mode. | 
| P1(config-if)#isis wide-metric 1000 | Configure the ISIS wide-metric  for interface | 
| P1(config-if)#exit | Exit interface mode. | 
| P1(config)#exit | Exit configure mode | 
| P1(config)#commit | Commit the candidate configuration to the running configuration. | 
P5
 
| P5#configure terminal | Enter configure mode. | 
| P5(config)#interface eth3 | Enter interface mode. | 
| P5(config-if)#isis wide-metric 1000 | Configure the ISIS wide-metric  for interface  | 
| P5(config-if)#exit | Exit interface mode. | 
| P5(config)#exit | Exit configure mode | 
| P5(config)#commit | Commit the candidate configuration to the running configuration. | 
Validation
P1
P1#show isis tilfa pq
IS-IS Level-1 Link State Database:
Node: 0000.0000.0001.00-00
  P node: 0000.0000.0004.00-00 primary dist:20
  P node: 0000.0000.0005.00-00 primary dist:30
  P node: 0000.0000.0006.00-00 primary dist:40
  P node: 0000.0000.0007.00-00 primary dist:20
  P node: 0000.0000.0003.00-00 primary dist:10
  P node: 0000.0000.0006.00-00 primary dist:40
  No PQ Node found on backup path
 
Node: 0000.0000.0003.00-00
  P node: 0000.0000.0004.00-00 primary dist:20
  P node: 0000.0000.0005.00-00 primary dist:30
  P node: 0000.0000.0007.00-00 primary dist:20
  P node: 0000.0000.0006.00-00 primary dist:40
  P node: 0000.0000.0001.00-00 primary dist:10
  Q node: 0000.0000.0004.00-00 primary dist:20
  Q node: 0000.0000.0005.00-00 primary dist:30
  Q node: 0000.0000.0006.00-00 primary dist:40
  Q node: 0000.0000.0007.00-00 primary dist:20
  PQ Node: 0000.0000.0006.00-00 backup dist:1000
 
Node: 0000.0000.0004.00-00
  P node: 0000.0000.0004.00-00 primary dist:20
  P node: 0000.0000.0005.00-00 primary dist:30
  P node: 0000.0000.0007.00-00 primary dist:20
  P node: 0000.0000.0006.00-00 primary dist:40
  P node: 0000.0000.0001.00-00 primary dist:10
  Q node: 0000.0000.0004.00-00 primary dist:20
  Q node: 0000.0000.0005.00-00 primary dist:30
  Q node: 0000.0000.0006.00-00 primary dist:40
  Q node: 0000.0000.0007.00-00 primary dist:20
  PQ Node: 0000.0000.0006.00-00 backup dist:1000
 
Node: 0000.0000.0005.00-00
  P node: 0000.0000.0004.00-00 primary dist:20
  P node: 0000.0000.0005.00-00 primary dist:30
  P node: 0000.0000.0007.00-00 primary dist:20
  P node: 0000.0000.0006.00-00 primary dist:40
  P node: 0000.0000.0001.00-00 primary dist:10
  Q node: 0000.0000.0004.00-00 primary dist:20
  Q node: 0000.0000.0005.00-00 primary dist:30
  Q node: 0000.0000.0006.00-00 primary dist:40
  Q node: 0000.0000.0007.00-00 primary dist:20
  PQ Node: 0000.0000.0006.00-00 backup dist:1000
 
Node: 0000.0000.0006.00-00
  P node: 0000.0000.0004.00-00 primary dist:20
  P node: 0000.0000.0005.00-00 primary dist:30
  P node: 0000.0000.0007.00-00 primary dist:20
  P node: 0000.0000.0006.00-00 primary dist:40
  P node: 0000.0000.0001.00-00 primary dist:10
  Q node: 0000.0000.0004.00-00 primary dist:20
  Q node: 0000.0000.0005.00-00 primary dist:30
  Q node: 0000.0000.0006.00-00 primary dist:40
  Q node: 0000.0000.0007.00-00 primary dist:20
  PQ Node: 0000.0000.0006.00-00 backup dist:1000
 
Node: 0000.0000.0007.00-00
  P node: 0000.0000.0004.00-00 primary dist:20
  P node: 0000.0000.0005.00-00 primary dist:30
  P node: 0000.0000.0007.00-00 primary dist:20
  P node: 0000.0000.0006.00-00 primary dist:40
  P node: 0000.0000.0001.00-00 primary dist:10
  Q node: 0000.0000.0004.00-00 primary dist:20
  Q node: 0000.0000.0005.00-00 primary dist:30
  Q node: 0000.0000.0006.00-00 primary dist:40
  Q node: 0000.0000.0007.00-00 primary dist:20
  PQ Node: 0000.0000.0006.00-00 backup dist:1000
 
P1# P1#show ip isis route tilfa
 
Tag   : 1  VRF : default
Codes : L1 - IS-IS level-1, L2 - IS-IS level-2,
        C - Connected Routes, ia - IS-IS inter area
 
1.1.1.1/32
 L1: Primary Path Nexthop   : 10.1.2.1, eth1
   Route ftnix :1  ilmix :5
   SR Incoming Label   : 16001
   SR outgoing Label   : 3
   NO PQ node
   NO Backup
 
 
1.1.1.2/32
 C: Primary Path Nexthop   : 0.0.0.0, lo
   Route ftnix :0  ilmix :1
   SR Incoming Label   : 16002
   No SR outgoing Label
   NO PQ node
   NO Backup
 
 
1.1.1.3/32
 L1: Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix :2  ilmix :6
   SR Incoming Label   : 16003
   SR outgoing Label   : 3
   PQ node : 1.1.1.6
   Backup ftnix :10   ilmix :47
   Backup outgoing Label   : 16003
   Bypass_trunk id :2203
   Backup out interface : eth3
 
 
1.1.1.4/32
 L1: Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix :3  ilmix :7
   SR Incoming Label   : 16004
   SR outgoing Label   : 16004
   PQ node : 1.1.1.6
   Backup ftnix :11   ilmix :48
   Backup outgoing Label   : 16004
   Bypass_trunk id :2203
   Backup out interface : eth3
 
 
1.1.1.5/32
 L1: Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix :4  ilmix :8
   SR Incoming Label   : 16005
   SR outgoing Label   : 16005
   PQ node : 1.1.1.6
   Backup ftnix :12   ilmix :49
   Backup outgoing Label   : 16005
   Bypass_trunk id :2203
   Backup out interface : eth3
 
 
1.1.1.6/32
 L1: Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix :5  ilmix :15
   SR Incoming Label   : 16006
   SR outgoing Label   : 16006
   PQ node : 1.1.1.6
   Backup ftnix :13   ilmix :50
   Backup outgoing Label   : 16006
   Bypass_trunk id :2203
   Backup out interface : eth3
 
   Trunk : 2203 :1.1.1.6_nh_10007   ftn_ix : 15 ref_cnt:7
   Number Of outgoing label : 1
    16006
   Nexthop address : 10.2.6.2
 
 
1.1.1.7/32
 L1: Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix :6  ilmix :40
   SR Incoming Label   : 16007
   SR outgoing Label   : 16007
   PQ node : 1.1.1.6
   Backup ftnix :14   ilmix :53
   Backup outgoing Label   : 16007
   Bypass_trunk id :2203
   Backup out interface : eth3
 
P1#
P1#show mpls ilm-table
Codes: > - installed ILM, * - selected ILM, p - stale ILM
        K - CLI ILM, T - MPLS-TP, s - Stitched ILM
       S - SNMP, L - LDP, R - RSVP, C - CRLDP
       B - BGP , K - CLI , V - LDP_VC, I - IGP_SHORTCUT
       O - OSPF/OSPF6 SR, i - ISIS SR, k - SR CLI
       P - SR Policy, U - unknown
 
Code    FEC/VRF/L2CKT    ILM-ID      In-Label    Out-Label   In-Intf    Out-Intf/VRF       Nexthop                   LSP-Type
   i>   10.1.2.1/32        2           24960       3           N/A        eth1              10.1.2.1                  LSP_DEFAULT
   i>   1.1.1.4/32         7           16004       16004       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   1.1.1.4/32         48          16004       16004       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   1.1.1.2/32         1           16002       Nolabel     N/A        N/A              127.0.0.1                 LSP_DEFAULT
   i>   1.1.1.1/32         5           16001       3           N/A        eth1              10.1.2.1                  LSP_DEFAULT
   i>   1.1.1.3/32         6           16003       3           N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   1.1.1.3/32         47          16003       16003       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   1.1.1.6/32         15          16006       16006       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   1.1.1.6/32         50          16006       16006       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   1.1.1.5/32         8           16005       16005       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   1.1.1.5/32         49          16005       16005       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   1.1.1.7/32         40          16007       16007       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   1.1.1.7/32         53          16007       16007       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   10.2.3.2/32        3           24961       3           N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   10.2.3.2/32        54          24961       16003       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   10.2.6.2/32        4           24962       3           N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   10.2.6.2/32        55          24962       16006       N/A        eth2              10.2.6.2                  LSP_DEFAULT
P1#
P1#show mpls forwarding-table
Codes: > - installed FTN, * - selected FTN, p - stale FTN,
       B - BGP FTN, K - CLI FTN, t - tunnel, P - SR Policy FTN,
       L - LDP FTN, R - RSVP-TE FTN, S - SNMP FTN, I - IGP-Shortcut,
       U - unknown FTN, O - SR-OSPF FTN, i - SR-ISIS FTN, k - SR-CLI FTN
 
Code    FEC                 FTN-ID    Nhlfe-ID  Tunnel-id   Pri   LSP-Type     Out-Label    Out-Intf    ELC   Nexthop
   i>   1.1.1.1/32          1         5         0           Yes   LSP_DEFAULT  3            eth1         No    10.1.2.1
   i>   1.1.1.3/32          2         3         0           Yes   LSP_DEFAULT  3            eth2         No    10.2.3.2
   i>   1.1.1.3/32          10        15        0           No    LSP_DEFAULT  16003        -           No    10.2.6.2
   i>   1.1.1.4/32          3         7         0           Yes   LSP_DEFAULT  16004        eth2         No    10.2.3.2
   i>   1.1.1.4/32          11        20        0           No    LSP_DEFAULT  16004        -           No    10.2.6.2
   i>   1.1.1.5/32          4         8         0           Yes   LSP_DEFAULT  16005        eth2         No    10.2.3.2
   i>   1.1.1.5/32          12        21        0           No    LSP_DEFAULT  16005        eth3         No    10.2.6.2
   i>   1.1.1.6/32          5         10        0           Yes   LSP_DEFAULT  16006        eth2         No    10.2.3.2
   i>   1.1.1.6/32          13        22        0           No    LSP_DEFAULT  16006        eth3         No    10.2.6.2
   i>   1.1.1.6/32          15        26        2203        Yes   LSP_DEFAULT  16006        eth3         No    10.2.6.2
   i>   1.1.1.7/32          6         11        0           Yes   LSP_DEFAULT  16007        eth2         No    10.2.3.2
   i>   1.1.1.7/32          14        24        0           No    LSP_DEFAULT  16007        -           No    10.2.6.2
   K>   202.1.1.0/24        7         -         -           -     LSP_DEFAULT  -            eth2         No    1.1.1.7
P1#show mpls ftn-table 1.1.1.6/32
 Primary FTN entry with FEC: 1.1.1.6/32, id: 5, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to LSP, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, Description: N/A, Color: 0
     Cross connect ix: 9, in intf: - in label: 0 out-segment ix: 19
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 19, owner: OSPF-SR, Stale: NO, OSPF-SR out intf: eth2, transport out intf: N/A, out label: 16006
    Nexthop addr: 10.2.3.2        cross connect ix: 9, op code: Push and Lookup
 
 
 Non-primary FTN entry with FEC: 1.1.1.6/32, id: 13, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 12, in intf: - in label: 0 out-segment ix: 25
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 25, owner: ISIS-SR, Stale: NO, out intf: eth3, out label: 16006
    Nexthop addr: 10.2.6.2        cross connect ix: 12, op code: Push
 
  bypass_ftn_ix 15
 
 Primary FTN entry with FEC: 1.1.1.6/32, id: 15, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 2203, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 12, in intf: - in label: 0 out-segment ix: 25
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 25, owner: ISIS-SR, Stale: NO, out intf: eth3, out label: 16006
    Nexthop addr: 10.2.6.2        cross connect ix: 12, op code: Push
 
P1#
 
P1#show mpls ftn-table 1.1.1.7/32
 Primary FTN entry with FEC: 1.1.1.7/32, id: 6, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to LSP, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, Description: N/A, Color: 0
     Cross connect ix: 4, in intf: - in label: 0 out-segment ix: 4
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 4, owner: ISIS-SR, Stale: NO, out intf: eth2, out label: 16007
    Nexthop addr: 10.2.3.2        cross connect ix: 4, op code: Push
 
 
 Non-primary FTN entry with FEC: 1.1.1.7/32, id: 14, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 11, in intf: - in label: 0 out-segment ix: 23
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 23, owner: ISIS-SR, Stale: NO, ISIS-SR out intf: eth3, transport out intf: N/A, out label: 16007
    Nexthop addr: 10.2.6.2        cross connect ix: 11, op code: Push and Lookup
 
  bypass_ftn_ix 15
 
P1#
Topology
 
TI-LFA FRR path using Adjacent P and Q Nodes
TI-LFA FRR Path using Adjacent P and Q nodes with OSPF-SR
P4
 
| P4#configure terminal | Enter configure mode. | 
| P4(config)#interface eth2 | Enter interface mode. | 
| P4(config-if)# ip ospf cost 1000 | Configure the OSPF cost of the interface | 
| P4(config-if)#exit | Exit interface mode. | 
| P4(config)#exit | Exit configure mode | 
| P4(config)#commit | Commit the candidate configuration to the running configuration. | 
P3
 
| P3#configure terminal | Enter configure mode. | 
| P3(config)#interface eth2 | Enter interface mode. | 
| P3(config-if)# ip ospf cost 1000 | Configure the OSPF cost of the interface | 
| P3(config-if)#exit | Exit interface mode. | 
| P3(config)#exit | Exit configure mode | 
| P3(config)#commit | Commit the candidate configuration to the running configuration. | 
Validation
P1
P1#show ip ospf tilfa-backup-path
 
OSPF process 100:
Route [1.1.1.1]
   NO PQ node
Route [1.1.1.2]
Route [1.1.1.3]
   P-node: 1.1.1.5    Q-node: 1.1.1.4
Route [1.1.1.4]
   P-node: 1.1.1.5    Q-node: 1.1.1.4
Route [1.1.1.5]
   P-node: 1.1.1.4    Q-node: 1.1.1.5
Route [1.1.1.6]
   P-node: 1.1.1.4    Q-node: 1.1.1.5
Route [1.1.1.7]
   P-node: 1.1.1.5    Q-node: 1.1.1.4
Route [10.1.2.0]
Route [10.2.3.0]
Route [10.2.6.0]
Route [10.3.4.0]
Route [10.3.7.0]
Route [10.4.5.0]
Route [10.5.6.0]
Neighbor [1.1.1.1]
Neighbor [1.1.1.3]
   P-node: 1.1.1.5    Q-node: 1.1.1.4
Neighbor [1.1.1.6]
   P-node: 1.1.1.4    Q-node: 1.1.1.5
 
Displaying vertex-info in tilfa_network table
Vertex [1.1.1.1]
  P node: 1.1.1.4 dist: 2
  P node: 1.1.1.7 dist: 2
  P node: 1.1.1.3 dist: 1
  P node: 1.1.1.5 dist: 2
  P node: 1.1.1.6 dist: 1
 
Vertex [1.1.1.2]
  No P Nodes
  No Q Nodes
 
Vertex [1.1.1.3]
  P node: 1.1.1.1 dist: 1
  P node: 1.1.1.5 dist: 2
  P node: 1.1.1.6 dist: 1
  Q node: 1.1.1.4 dist: 2
  Q node: 1.1.1.7 dist: 2
    P-node: 1.1.1.5    Q-node: 1.1.1.4
    Backup out-interface: eth3
 
Vertex [1.1.1.4]
  P node: 1.1.1.1 dist: 1
  P node: 1.1.1.5 dist: 2
  P node: 1.1.1.6 dist: 1
  Q node: 1.1.1.4 dist: 2
  Q node: 1.1.1.7 dist: 2
    P-node: 1.1.1.5    Q-node: 1.1.1.4
    Backup out-interface: eth3
 
Vertex [1.1.1.5]
  P node: 1.1.1.1 dist: 1
  P node: 1.1.1.4 dist: 2
  P node: 1.1.1.7 dist: 2
  P node: 1.1.1.3 dist: 1
  Q node: 1.1.1.5 dist: 2
    P-node: 1.1.1.4    Q-node: 1.1.1.5
    Backup out-interface: eth2
 
Vertex [1.1.1.6]
  P node: 1.1.1.1 dist: 1
  P node: 1.1.1.4 dist: 2
  P node: 1.1.1.7 dist: 2
  P node: 1.1.1.3 dist: 1
  Q node: 1.1.1.5 dist: 2
    P-node: 1.1.1.4    Q-node: 1.1.1.5
    Backup out-interface: eth2
 
Vertex [1.1.1.7]
  P node: 1.1.1.1 dist: 1
  P node: 1.1.1.5 dist: 2
  P node: 1.1.1.6 dist: 1
  Q node: 1.1.1.4 dist: 2
  Q node: 1.1.1.7 dist: 2
    P-node: 1.1.1.5    Q-node: 1.1.1.4
    Backup out-interface: eth3
 
P1# P1#show ip ospf tilfa-repair-list
 
1.1.1.1/32
   Primary Path Metric   :2
   Primary Path Nexthop   : 10.1.2.1, eth1
   Route ftnix:1 ilmix:1
   SR Incoming Label   : 16001
   SR outgoing Label   : 3
   NO PQ node
 
1.1.1.2/32
1.1.1.3/32
   Primary Path Metric   :2
   Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix:2 ilmix:4
   SR Incoming Label   : 16003
   SR outgoing Label   : 3
   P-node: 1.1.1.5   Q-node: 1.1.1.4
 
   Backup ftnix:8 ilmix:33
   Backup outgoing Label   : 16003
   Bypass_trunk id :101
   Backup out interface: eth3
 
1.1.1.4/32
   Primary Path Metric   :3
   Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix:3 ilmix:5
   SR Incoming Label   : 16004
   SR outgoing Label   : 16004
   P-node: 1.1.1.5   Q-node: 1.1.1.4
 
   Backup ftnix:9 ilmix:34
   Backup outgoing Label   : 16004
   Bypass_trunk id :101
   Backup out interface: eth3
 
   Bypass-Trunk: 102 Name: 1.1.1.4_1.1.1.5_nexthop__10006 ftn_ix:7
   ftn_info->trunk_ftn_ix   : 7
   Number Of outgoing label 2:
    16004
    24321
   Nexthop address: 10.2.3.2
 
1.1.1.5/32
   Primary Path Metric   :3
   Primary Path Nexthop   : 10.2.6.2, eth3
   Route ftnix:4 ilmix:6
   SR Incoming Label   : 16005
   SR outgoing Label   : 16005
   P-node: 1.1.1.4   Q-node: 1.1.1.5
 
   Backup ftnix:10 ilmix:35
   Backup outgoing Label   : 16005
   Bypass_trunk id :102
   Backup out interface: eth2
 
   Bypass-Trunk: 101 Name: 1.1.1.5_1.1.1.4_nexthop__10007 ftn_ix:6
   ftn_info->trunk_ftn_ix   : 6
   Number Of outgoing label 2:
    16005
    24320
   Nexthop address: 10.2.6.2
 
1.1.1.6/32
   Primary Path Metric   :2
   Primary Path Nexthop   : 10.2.6.2, eth3
   Route ftnix:5 ilmix:8
   SR Incoming Label   : 16006
   SR outgoing Label   : 3
   P-node: 1.1.1.4   Q-node: 1.1.1.5
 
   Backup ftnix:11 ilmix:36
   Backup outgoing Label   : 16006
   Bypass_trunk id :102
   Backup out interface: eth2
 
1.1.1.7/32
   Primary Path Metric   :3
   Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix:12 ilmix:15
   SR Incoming Label   : 16007
   SR outgoing Label   : 16007
   P-node: 1.1.1.5   Q-node: 1.1.1.4
 
   Backup ftnix:14 ilmix:37
   Backup outgoing Label   : 16007
   Bypass_trunk id :101
   Backup out interface: eth3
 
10.1.2.0/24
10.2.3.0/24
10.2.6.0/24
10.3.4.0/24
10.3.7.0/24
10.4.5.0/24
10.5.6.0/24
P1#
 
P1#show mpls ilm-table
Codes: > - installed ILM, * - selected ILM, p - stale ILM
        K - CLI ILM, T - MPLS-TP, s - Stitched ILM
       S - SNMP, L - LDP, R - RSVP, C - CRLDP
       B - BGP , K - CLI , V - LDP_VC, I - IGP_SHORTCUT
       O - OSPF/OSPF6 SR, i - ISIS SR, k - SR CLI
       P - SR Policy, U - unknown
 
Code    FEC/VRF/L2CKT    ILM-ID      In-Label    Out-Label   In-Intf    Out-Intf/VRF       Nexthop                   LSP-Type
   O>   1.1.1.6/32         8           16006       3           N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   1.1.1.6/32         36          16006       16006       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.4/32         5           16004       16004       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.4/32         34          16004       16004       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   1.1.1.3/32         4           16003       3           N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.3/32         33          16003       16003       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   1.1.1.1/32         1           16001       3           N/A        eth1              10.1.2.1                  LSP_DEFAULT
   O>   1.1.1.5/32         6           16005       16005       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   1.1.1.5/32         35          16005       16005       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   10.1.2.1/32        2           24320       3           N/A        eth1              10.1.2.1                  LSP_DEFAULT
   O>   1.1.1.7/32         15          16007       16007       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.7/32         37          16007       16007       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   10.2.3.2/32        3           24321       3           N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   10.2.3.2/32        38          24321       16003       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   10.2.6.2/32        7           24322       3           N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   10.2.6.2/32        39          24322       16006       N/A        eth2              10.2.3.2                  LSP_DEFAULT
P1#
 
P1#show mpls ilm-table
Codes: > - installed ILM, * - selected ILM, p - stale ILM
        K - CLI ILM, T - MPLS-TP, s - Stitched ILM
       S - SNMP, L - LDP, R - RSVP, C - CRLDP
       B - BGP , K - CLI , V - LDP_VC, I - IGP_SHORTCUT
       O - OSPF/OSPF6 SR, i - ISIS SR, k - SR CLI
       P - SR Policy, U - unknown
 
Code    FEC/VRF/L2CKT    ILM-ID      In-Label    Out-Label   In-Intf    Out-Intf/VRF       Nexthop                   LSP-Type
   O>   10.1.2.1/32        2           24320       3           N/A        eth1              10.1.2.1                  LSP_DEFAULT
   O>   1.1.1.4/32         8           16004       16004       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.4/32         60          16004       16004       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   1.1.1.3/32         3           16003       3           N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.3/32         59          16003       16003       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   1.1.1.1/32         1           16001       3           N/A        eth1              10.1.2.1                  LSP_DEFAULT
   O>   1.1.1.6/32         4           16006       3           N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   1.1.1.6/32         62          16006       16006       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.5/32         15          16005       16005       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   1.1.1.5/32         61          16005       16005       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.7/32         7           16007       16007       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   1.1.1.7/32         63          16007       16007       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   10.2.3.2/32        5           24321       3           N/A        eth2              10.2.3.2                  LSP_DEFAULT
   O>   10.2.3.2/32        64          24321       16003       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   10.2.6.2/32        6           24322       3           N/A        eth3              10.2.6.2                  LSP_DEFAULT
   O>   10.2.6.2/32        65          24322       16006       N/A        eth2              10.2.3.2                  LSP_DEFAULT
P#
 
P1#show mpls forwarding-table
Codes: > - installed FTN, * - selected FTN, p - stale FTN,
       B - BGP FTN, K - CLI FTN, t - tunnel, P - SR Policy FTN,
       L - LDP FTN, R - RSVP-TE FTN, S - SNMP FTN, I - IGP-Shortcut,
       U - unknown FTN, O - SR-OSPF FTN, i - SR-ISIS FTN, k - SR-CLI FTN
 
Code    FEC                 FTN-ID    Nhlfe-ID  Tunnel-id   Pri   LSP-Type     Out-Label    Out-Intf    ELC   Nexthop
   O>   1.1.1.1/32          1         2         0           Yes   LSP_DEFAULT  3            eth1         No    10.1.2.1
   O>   1.1.1.3/32          2         4         0           Yes   LSP_DEFAULT  3            eth2         No    10.2.3.2
   O>   1.1.1.3/32          8         13        0           No    LSP_DEFAULT  16003        -           No    10.2.6.2
   O>   1.1.1.4/32          3         6         0           Yes   LSP_DEFAULT  16004        eth2         No    10.2.3.2
   O>   1.1.1.4/32          9         15        0           No    LSP_DEFAULT  16004        -           No    10.2.6.2
   O>   1.1.1.4/32          7         11        102         Yes   LSP_DEFAULT  16004        eth2         No    10.2.3.2
   O>   1.1.1.5/32          4         8         0           Yes   LSP_DEFAULT  16005        eth3         No    10.2.6.2
   O>   1.1.1.5/32          10        18        0           No    LSP_DEFAULT  16005        -           No    10.2.3.2
   O>   1.1.1.5/32          6         7         101         Yes   LSP_DEFAULT  16005        -           No    10.2.6.2
   O>   1.1.1.6/32          5         10        0           Yes   LSP_DEFAULT  3            eth3         No    10.2.6.2
   O>   1.1.1.6/32          11        20        0           No    LSP_DEFAULT  16006        -           No    10.2.3.2
   O>   1.1.1.7/32          12        22        0           Yes   LSP_DEFAULT  16007        eth2         No    10.2.3.2
   O>   1.1.1.7/32          14        24        0           No    LSP_DEFAULT  16007        -           No    10.2.6.2
   K>   202.1.1.0/24        13        -         -           -     LSP_DEFAULT  -            eth2         No    1.1.1.7
P1#
 
P1#show mpls ftn-table 1.1.1.5/32
 Primary FTN entry with FEC: 1.1.1.5/32, id: 4, row status: Active, Tunnel-Policy: N/A
  Owner: OSPF-SR, distance: 110, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 7, in intf: - in label: 0 out-segment ix: 16
      Owner: OSPF-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 16, owner: OSPF-SR, Stale: NO, OSPF-SR out intf: eth3, transport out intf: N/A, out label: 16005
    Nexthop addr: 10.2.6.2        cross connect ix: 7, op code: Push and Lookup
 
 
 Non-primary FTN entry with FEC: 1.1.1.5/32, id: 10, row status: Active, Tunnel-Policy: N/A
  Owner: OSPF-SR, distance: 110, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 8, in intf: - in label: 0 out-segment ix: 17
      Owner: OSPF-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 17, owner: OSPF-SR, Stale: NO, OSPF-SR out intf: eth2, transport out intf: N/A, out label: 16005
    Nexthop addr: 10.2.3.2        cross connect ix: 8, op code: Push and Lookup
 
  bypass_ftn_ix 7
 
 Primary FTN entry with FEC: 1.1.1.5/32, id: 6, row status: Active, Tunnel-Policy: N/A
  Owner: OSPF-SR, distance: 110, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 101, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 7, in intf: - in label: 0 out-segment ix: 16
      Owner: OSPF-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 16, owner: OSPF-SR, Stale: NO, OSPF-SR out intf: eth3, transport out intf: N/A, out label: 16005\24320
    Nexthop addr: 10.2.6.2        cross connect ix: 7, op code: Push and Lookup
 
 
P1#
 
P1#show mpls ftn-table 1.1.1.4/32
 Primary FTN entry with FEC: 1.1.1.4/32, id: 3, row status: Active, Tunnel-Policy: N/A
  Owner: OSPF-SR, distance: 110, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 3, in intf: - in label: 0 out-segment ix: 5
      Owner: OSPF-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 5, owner: OSPF-SR, Stale: NO, out intf: eth2, out label: 16004
    Nexthop addr: 10.2.3.2        cross connect ix: 3, op code: Push
 
 
 Non-primary FTN entry with FEC: 1.1.1.4/32, id: 9, row status: Active, Tunnel-Policy: N/A
  Owner: OSPF-SR, distance: 110, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 6, in intf: - in label: 0 out-segment ix: 14
      Owner: OSPF-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 14, owner: OSPF-SR, Stale: NO, OSPF-SR out intf: eth3, transport out intf: N/A, out label: 16004
    Nexthop addr: 10.2.6.2        cross connect ix: 6, op code: Push and Lookup
 
  bypass_ftn_ix 6
 
 Primary FTN entry with FEC: 1.1.1.4/32, id: 7, row status: Active, Tunnel-Policy: N/A
  Owner: OSPF-SR, distance: 110, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 102, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 3, in intf: - in label: 0 out-segment ix: 5
      Owner: OSPF-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 5, owner: OSPF-SR, Stale: NO, out intf: eth2, out label: 16004\24321
    Nexthop addr: 10.2.3.2        cross connect ix: 3, op code: Push
 
 
P1#
 
P1#show mpls ftn-table 1.1.1.7/32
 Primary FTN entry with FEC: 1.1.1.7/32, id: 12, row status: Active, Tunnel-Policy: N/A
  Owner: OSPF-SR, distance: 110, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 10, in intf: - in label: 0 out-segment ix: 21
      Owner: OSPF-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 21, owner: OSPF-SR, Stale: NO, out intf: eth2, out label: 16007
    Nexthop addr: 10.2.3.2        cross connect ix: 10, op code: Push
 
 
 Non-primary FTN entry with FEC: 1.1.1.7/32, id: 14, row status: Active, Tunnel-Policy: N/A
  Owner: OSPF-SR, distance: 110, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 11, in intf: - in label: 0 out-segment ix: 23
      Owner: OSPF-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 23, owner: OSPF-SR, Stale: NO, OSPF-SR out intf: eth3, transport out intf: N/A, out label: 16007
    Nexthop addr: 10.2.6.2        cross connect ix: 11, op code: Push and Lookup
 
  bypass_ftn_ix 6
 
P1#
TI-LFA FRR Path using Adjacent P and Q nodes with ISIS-SR
P4
 
| P4#configure terminal | Enter configure mode. | 
| P4(config)#interface eth2 | Enter interface mode. | 
| P4(config-if)#isis wide-metric 1000 | Configure the ISIS wide-metric for the interface | 
| P4(config-if)#exit | Exit interface mode. | 
| P4(config)#exit | Exit configure mode | 
| P4(config)#commit | Commit the candidate configuration to the running configuration. | 
P3
 
| P3#configure terminal | Enter configure mode. | 
| P3(config)#interface eth2 | Enter interface mode. | 
| P3(config-if)#isis wide-metric 1000 | Configure the ISIS wide-metric for the interface | 
| P3(config-if)#exit | Exit interface mode. | 
| P3(config)#exit | Exit configure mode | 
| P3(config)#commit | Commit the candidate configuration to the running configuration. | 
Validation 
P1
P1#show isis tilfa pq
 
IS-IS Level-1 Link State Database:
 
Node: 0000.0000.0001.00-00
  P node: 0000.0000.0004.00-00 primary dist:20
  P node: 0000.0000.0007.00-00 primary dist:20
  P node: 0000.0000.0003.00-00 primary dist:10
  P node: 0000.0000.0005.00-00 primary dist:20
  P node: 0000.0000.0006.00-00 primary dist:10
  No PQ Node found on backup path
 
Node: 0000.0000.0003.00-00
  P node: 0000.0000.0005.00-00 primary dist:20
  P node: 0000.0000.0006.00-00 primary dist:10
  P node: 0000.0000.0001.00-00 primary dist:10
  Q node: 0000.0000.0004.00-00 primary dist:20
  Q node: 0000.0000.0007.00-00 primary dist:20
 P-Node: 0000.0000.0005.00-00 backup dist:20
 Q-Node: 0000.0000.0004.00-00 backup dist:1020
 
Node: 0000.0000.0004.00-00
  P node: 0000.0000.0005.00-00 primary dist:20
  P node: 0000.0000.0006.00-00 primary dist:10
  P node: 0000.0000.0001.00-00 primary dist:10
  Q node: 0000.0000.0004.00-00 primary dist:20
  Q node: 0000.0000.0007.00-00 primary dist:20
 P-Node: 0000.0000.0005.00-00 backup dist:20
 Q-Node: 0000.0000.0004.00-00 backup dist:1020
 
Node: 0000.0000.0005.00-00
  P node: 0000.0000.0004.00-00 primary dist:20
  P node: 0000.0000.0007.00-00 primary dist:20
  P node: 0000.0000.0003.00-00 primary dist:10
  P node: 0000.0000.0001.00-00 primary dist:10
  Q node: 0000.0000.0005.00-00 primary dist:20
 P-Node: 0000.0000.0004.00-00 backup dist:20
 Q-Node: 0000.0000.0005.00-00 backup dist:1020
 
Node: 0000.0000.0006.00-00
  P node: 0000.0000.0004.00-00 primary dist:20
  P node: 0000.0000.0007.00-00 primary dist:20
  P node: 0000.0000.0003.00-00 primary dist:10
  P node: 0000.0000.0001.00-00 primary dist:10
  Q node: 0000.0000.0005.00-00 primary dist:20
 P-Node: 0000.0000.0004.00-00 backup dist:20
 Q-Node: 0000.0000.0005.00-00 backup dist:1020
 
Node: 0000.0000.0007.00-00
  P node: 0000.0000.0005.00-00 primary dist:20
  P node: 0000.0000.0006.00-00 primary dist:10
  P node: 0000.0000.0001.00-00 primary dist:10
  Q node: 0000.0000.0004.00-00 primary dist:20
  Q node: 0000.0000.0007.00-00 primary dist:20
 P-Node: 0000.0000.0005.00-00 backup dist:20
 Q-Node: 0000.0000.0004.00-00 backup dist:1020
 
P1#
 
P1#show ip isis route tilfa
 
Tag   : 1  VRF : default
Codes : L1 - IS-IS level-1, L2 - IS-IS level-2,
        C - Connected Routes, ia - IS-IS inter area
 
1.1.1.1/32
 L1: Primary Path Nexthop   : 10.1.2.1, eth1
   Route ftnix :1  ilmix :5
   SR Incoming Label   : 16001
   SR outgoing Label   : 3
   NO PQ node
   NO Backup
 
 
1.1.1.2/32
 C: Primary Path Nexthop   : 0.0.0.0, lo
   Route ftnix :0  ilmix :1
   SR Incoming Label   : 16002
   No SR outgoing Label
   NO PQ node
   NO Backup
 
 
1.1.1.3/32
 L1: Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix :2  ilmix :6
   SR Incoming Label   : 16003
   SR outgoing Label   : 3
   P node : 1.1.1.5
   Q node : 1.1.1.4
   Backup ftnix :10   ilmix :47
   Backup outgoing Label   : 16003
   Bypass_trunk id :2203
   Backup out interface : eth3
 
 
1.1.1.4/32
 L1: Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix :3  ilmix :7
   SR Incoming Label   : 16004
   SR outgoing Label   : 16004
   P node : 1.1.1.5
   Q node : 1.1.1.4
   Backup ftnix :11   ilmix :48
   Backup outgoing Label   : 16004
   Bypass_trunk id :2203
   Backup out interface : eth3
 
   Trunk : 2204 :1.1.1.4_1.1.1.5_nh_10006   ftn_ix : 16 ref_cnt:3
   Number Of outgoing label : 2
    16004
    24960
   Nexthop address : 10.2.3.2
 
 
1.1.1.5/32
 L1: Primary Path Nexthop   : 10.2.6.2, eth3
   Route ftnix :4  ilmix :8
   SR Incoming Label   : 16005
   SR outgoing Label   : 16005
   P node : 1.1.1.4
   Q node : 1.1.1.5
   Backup ftnix :12   ilmix :49
   Backup outgoing Label   : 16005
   Bypass_trunk id :2204
   Backup out interface : eth2
 
   Trunk : 2203 :1.1.1.5_1.1.1.4_nh_10007   ftn_ix : 15 ref_cnt:4
   Number Of outgoing label : 2
    16005
    24961
   Nexthop address : 10.2.6.2
 
 
1.1.1.6/32
 L1: Primary Path Nexthop   : 10.2.6.2, eth3
   Route ftnix :5  ilmix :15
   SR Incoming Label   : 16006
   SR outgoing Label   : 3
   P node : 1.1.1.4
   Q node : 1.1.1.5
   Backup ftnix :13   ilmix :50
   Backup outgoing Label   : 16006
   Bypass_trunk id :2204
   Backup out interface : eth2
 
 
1.1.1.7/32
 L1: Primary Path Nexthop   : 10.2.3.2, eth2
   Route ftnix :6  ilmix :40
   SR Incoming Label   : 16007
   SR outgoing Label   : 16007
   P node : 1.1.1.5
   Q node : 1.1.1.4
   Backup ftnix :14   ilmix :53
   Backup outgoing Label   : 16007
   Bypass_trunk id :2203
   Backup out interface : eth3
 
P1#
 
P1# show mpls ilm-table
Codes: > - installed ILM, * - selected ILM, p - stale ILM
        K - CLI ILM, T - MPLS-TP, s - Stitched ILM
       S - SNMP, L - LDP, R - RSVP, C - CRLDP
       B - BGP , K - CLI , V - LDP_VC, I - IGP_SHORTCUT
       O - OSPF/OSPF6 SR, i - ISIS SR, k - SR CLI
       P - SR Policy, U - unknown
 
Code    FEC/VRF/L2CKT    ILM-ID      In-Label    Out-Label   In-Intf    Out-Intf/VRF       Nexthop                   LSP-Type
   i>   10.1.2.1/32        2           24960       3           N/A        eth1              10.1.2.1                  LSP_DEFAULT
   i>   1.1.1.4/32         7           16004       16004       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   1.1.1.4/32         48          16004       16004       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   1.1.1.2/32         1           16002       Nolabel     N/A        N/A              127.0.0.1                 LSP_DEFAULT
   i>   1.1.1.1/32         5           16001       3           N/A        eth1              10.1.2.1                  LSP_DEFAULT
   i>   1.1.1.3/32         6           16003       3           N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   1.1.1.3/32         47          16003       16003       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   1.1.1.6/32         15          16006       3           N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   1.1.1.6/32         50          16006       16006       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   1.1.1.5/32         8           16005       16005       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   1.1.1.5/32         49          16005       16005       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   1.1.1.7/32         40          16007       16007       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   1.1.1.7/32         53          16007       16007       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   10.2.3.2/32        3           24961       3           N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   10.2.3.2/32        60          24961       16003       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   10.2.6.2/32        4           24962       3           N/A        eth3              10.2.6.2                  LSP_DEFAULT
   i>   10.2.6.2/32        61          24962       16006       N/A        eth2              10.2.3.2                  LSP_DEFAULT
P1#
 
P1#show mpls forwarding-table
Codes: > - installed FTN, * - selected FTN, p - stale FTN,
       B - BGP FTN, K - CLI FTN, t - tunnel, P - SR Policy FTN,
       L - LDP FTN, R - RSVP-TE FTN, S - SNMP FTN, I - IGP-Shortcut,
       U - unknown FTN, O - SR-OSPF FTN, i - SR-ISIS FTN, k - SR-CLI FTN
 
Code    FEC                 FTN-ID    Nhlfe-ID  Tunnel-id   Pri   LSP-Type     Out-Label    Out-Intf    ELC   Nexthop
   i>   1.1.1.1/32          1         5         0           Yes   LSP_DEFAULT  3            eth1         No    10.1.2.1
   i>   1.1.1.3/32          2         3         0           Yes   LSP_DEFAULT  3            eth2         No    10.2.3.2
   i>   1.1.1.3/32          10        15        0           No    LSP_DEFAULT  16003        -           No    10.2.6.2
   i>   1.1.1.4/32          3         7         0           Yes   LSP_DEFAULT  16004        eth2         No    10.2.3.2
   i>   1.1.1.4/32          11        20        0           No    LSP_DEFAULT  16004        -           No    10.2.6.2
   i>   1.1.1.4/32          16        26        2204        Yes   LSP_DEFAULT  16004        eth2         No    10.2.3.2
   i>   1.1.1.5/32          4         8         0           Yes   LSP_DEFAULT  16005        eth3         No    10.2.6.2
   i>   1.1.1.5/32          12        21        0           No    LSP_DEFAULT  16005        -           No    10.2.3.2
   i>   1.1.1.5/32          15        25        2203        Yes   LSP_DEFAULT  16005        eth3         No    10.2.6.2
   i>   1.1.1.6/32          5         10        0           Yes   LSP_DEFAULT  3            eth3         No    10.2.6.2
   i>   1.1.1.6/32          13        22        0           No    LSP_DEFAULT  16006        -           No    10.2.3.2
   i>   1.1.1.7/32          6         11        0           Yes   LSP_DEFAULT  16007        eth2         No    10.2.3.2
   i>   1.1.1.7/32          14        24        0           No    LSP_DEFAULT  16007        -           No    10.2.6.2
   K>   202.1.1.0/24        7         -         -           -     LSP_DEFAULT  -            eth2         No    1.1.1.7
P1#
 
P1#show mpls ftn-table
 Primary FTN entry with FEC: 1.1.1.1/32, id: 1, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to LSP, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, Description: N/A, Color: 0
     Cross connect ix: 1, in intf: - in label: 0 out-segment ix: 1
      Owner: N/A, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 1, owner: N/A, Stale: NO, out intf: eth1, out label: 3
    Nexthop addr: 10.1.2.1        cross connect ix: 1, op code: Push
 
 
 Primary FTN entry with FEC: 1.1.1.3/32, id: 2, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to LSP, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, Description: N/A, Color: 0
     Cross connect ix: 2, in intf: - in label: 0 out-segment ix: 2
      Owner: N/A, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 2, owner: N/A, Stale: NO, out intf: eth2, out label: 3
    Nexthop addr: 10.2.3.2        cross connect ix: 2, op code: Push
 
 
 Non-primary FTN entry with FEC: 1.1.1.3/32, id: 10, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 6, in intf: - in label: 0 out-segment ix: 14
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 14, owner: ISIS-SR, Stale: NO, ISIS-SR out intf: eth3, transport out intf: N/A, out label: 16003
    Nexthop addr: 10.2.6.2        cross connect ix: 6, op code: Push and Lookup
 
  bypass_ftn_ix 15
 
 Primary FTN entry with FEC: 1.1.1.4/32, id: 3, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to LSP, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, Description: N/A, Color: 0
     Cross connect ix: 3, in intf: - in label: 0 out-segment ix: 6
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 6, owner: ISIS-SR, Stale: NO, out intf: eth2, out label: 16004
    Nexthop addr: 10.2.3.2        cross connect ix: 3, op code: Push
 
 
 Non-primary FTN entry with FEC: 1.1.1.4/32, id: 11, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 10, in intf: - in label: 0 out-segment ix: 18
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 18, owner: ISIS-SR, Stale: NO, ISIS-SR out intf: eth3, transport out intf: N/A, out label: 16004
    Nexthop addr: 10.2.6.2        cross connect ix: 10, op code: Push and Lookup
 
  bypass_ftn_ix 15
 
 Primary FTN entry with FEC: 1.1.1.4/32, id: 16, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 2204, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 3, in intf: - in label: 0 out-segment ix: 6
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 6, owner: ISIS-SR, Stale: NO, out intf: eth2, out label: 16004\24960
    Nexthop addr: 10.2.3.2        cross connect ix: 3, op code: Push
 
 
 Primary FTN entry with FEC: 1.1.1.5/32, id: 4, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to LSP, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, Description: N/A, Color: 0
     Cross connect ix: 7, in intf: - in label: 0 out-segment ix: 16
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 16, owner: OSPF-SR, Stale: NO, out intf: eth3, out label: 16005
    Nexthop addr: 10.2.6.2        cross connect ix: 7, op code: Push
 
 
 Non-primary FTN entry with FEC: 1.1.1.5/32, id: 12, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 8, in intf: - in label: 0 out-segment ix: 17
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 17, owner: OSPF-SR, Stale: NO, OSPF-SR out intf: eth2, transport out intf: N/A, out label: 16005
    Nexthop addr: 10.2.3.2        cross connect ix: 8, op code: Push and Lookup
 
  bypass_ftn_ix 16
 
 Primary FTN entry with FEC: 1.1.1.5/32, id: 15, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 2203, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 7, in intf: - in label: 0 out-segment ix: 16
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 16, owner: OSPF-SR, Stale: NO, out intf: eth3, out label: 16005\24961
    Nexthop addr: 10.2.6.2        cross connect ix: 7, op code: Push
 
 
 Primary FTN entry with FEC: 1.1.1.6/32, id: 5, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to LSP, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, Description: N/A, Color: 0
     Cross connect ix: 5, in intf: - in label: 0 out-segment ix: 9
      Owner: N/A, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 9, owner: N/A, Stale: NO, out intf: eth3, out label: 3
    Nexthop addr: 10.2.6.2        cross connect ix: 5, op code: Push
 
 
 Non-primary FTN entry with FEC: 1.1.1.6/32, id: 13, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 9, in intf: - in label: 0 out-segment ix: 19
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 19, owner: OSPF-SR, Stale: NO, OSPF-SR out intf: eth2, transport out intf: N/A, out label: 16006
    Nexthop addr: 10.2.3.2        cross connect ix: 9, op code: Push and Lookup
 
  bypass_ftn_ix 16
 
 Primary FTN entry with FEC: 1.1.1.7/32, id: 6, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to LSP, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, Description: N/A, Color: 0
     Cross connect ix: 4, in intf: - in label: 0 out-segment ix: 4
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 4, owner: ISIS-SR, Stale: NO, out intf: eth2, out label: 16007
    Nexthop addr: 10.2.3.2        cross connect ix: 4, op code: Push
 
 
 Non-primary FTN entry with FEC: 1.1.1.7/32, id: 14, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 11, in intf: - in label: 0 out-segment ix: 23
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 23, owner: ISIS-SR, Stale: NO, ISIS-SR out intf: eth3, transport out intf: N/A, out label: 16007
    Nexthop addr: 10.2.6.2        cross connect ix: 11, op code: Push and Lookup
 
  bypass_ftn_ix 15
 
 Primary FTN entry with FEC: 202.1.1.0/24, id: 7, row status: Active, Tunnel-Policy: N/A
  Owner: CLI, distance: 115, Action-type: Redirect to LSP, Exp-bits: 0x0, Incoming DSCP: none
  Transport Tunnel id: 0, Protected LSP id: 0, Description: N/A, Color: 0
     Cross connect ix: 4, in intf: - in label: 0 out-segment ix: 4
      Owner: ISIS-SR, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 4, owner: ISIS-SR, Stale: NO, out intf: eth2, out label: 16007
    Nexthop addr: 10.2.3.2        cross connect ix: 4, op code: Push
 
P1#
TI-LFA FRR for SR-Policy
The active segment of a packet (ie., the top label of the packet as seen by the receiving router) that is being forwarded using an SR-policy can be protected upon failure of its primary outgoing interface by enabling FRR for the SR-policy.
P1
 
| P1#configure terminal | Enter configure mode | 
| P1(config)#segment-routing | Configuring segment-routing | 
| P1(config-sr)#traffic-engineering | Segment Routing traffic engineering | 
| P1(config-sr-te)#segment-list p5-p4-pe2 | Configure a segment-list | 
| P1(config-sr-sl)#index 10 segment-type-1 16006   | Configure the segment-list entry with index 10 and label as prefix-sid of P5 | 
| P1(config-sr-sl)#index 20 segment-type-1 16005   | Configure the segment-list entry with index 10 and label as prefix-sid of P4 | 
| P1(config-sr-sl)#index 30 segment-type-1 16007   | Configure the segment-list entry with index 10 and label as prefix-sid of PE2 | 
| P1(config-sr-sl)#exit-sr-sl | Exit segment-routing segment-list mode | 
| P1(config-sr-te)#policy to-pe2 | Configure an SR-policy | 
| P1(config-sr-pol)#color 11 end-point 1.1.1.7   | Configure SR-policy with key ie., color and end-point | 
| P1(config-sr-pol)#candidate-path 11 | Configure a candidate-path for the SR-policy | 
| P1(config-sr-pol-cp)#preference 100 | Configure the preference value for the candidate-path | 
| P1(config-sr-pol-cp)#explicit segment-list p5-p4-pe2 | Configure the candidate-path as explicit-path with segment- list | 
| P1(config-sr-pol-cp)#exit-pol-cp | Exit from SR policy candidate path configuration mode | 
| P1(config-sr-pol)#exit-sr-pol | Exit from SR policy configuration mode | 
| P1(config-sr-te)#policy-fast-reroute-enable | Enable segment-routing policy fast-reroute | 
| P1(config-sr-te)#exit | Exit segment-routing mode | 
| P1(config)#exit | Exit configure terminal mode | 
| P1(config)#commit | Commit the candidate configuration to the running configuration. | 
Validation
P1
 
P1#show mpls forwarding-table 1.1.1.7/32
Codes: > - installed FTN, * - selected FTN, p - stale FTN,
       B - BGP FTN, K - CLI FTN, t - tunnel, P - SR Policy FTN,
       L - LDP FTN, R - RSVP-TE FTN, S - SNMP FTN, I - IGP-Shortcut,
       U - unknown FTN, O - SR-OSPF FTN, i - SR-ISIS FTN, k - SR-CLI FTN
 
Code    FEC                 FTN-ID    Nhlfe-ID  Tunnel-id   Pri   LSP-Type     Out-Label    Out-Intf    ELC   Nexthop
   P>   1.1.1.7/32          8         13        1           Yes   LSP_DEFAULT  3            eth3         No    10.2.6.2
   P>   1.1.1.7/32          9         24        1           No    LSP_DEFAULT  16006        -           No    10.2.3.2
   i    1.1.1.7/32          6         4         0           Yes   LSP_DEFAULT  16007        eth2         No    10.2.3.2
   i    1.1.1.7/32          14        23        0           No    LSP_DEFAULT  16007        -           No    10.2.6.2
P1#
 
P1#show mpls ftn-table 1.1.1.7/32
 Primary FTN entry with FEC: 1.1.1.7/32, id: 8, row status: Active, Tunnel-Policy: N/A
  Owner: SR_POLICY, distance: 0, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 1, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 12, in intf: - in label: 0 out-segment ix: 12
      Owner: N/A, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 12, owner: N/A, Stale: NO, out intf: eth3, out label: 3\16005\16007
    Nexthop addr: 10.2.6.2        cross connect ix: 12, op code: Push
 
 
 Non-primary FTN entry with FEC: 1.1.1.7/32, id: 9, row status: Active, Tunnel-Policy: N/A
  Owner: SR_POLICY, distance: 0, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 1, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 13, in intf: - in label: 0 out-segment ix: 11
      Owner: SR_POLICY, Persistent: No, Admin Status: Up, Oper Status: Up
       Out-segment with ix: 11, owner: SR_POLICY, Stale: NO, SR_POLICY out intf: eth2, transport out intf: N/A, out label: 16006\16005\16007
    Nexthop addr: 10.2.3.2        cross connect ix: 13, op code: Push and Lookup
 
  bypass_ftn_ix 16
 
 Primary FTN entry with FEC: 1.1.1.7/32, id: 6, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to LSP, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, Description: N/A, Color: 0
     Cross connect ix: 4, in intf: - in label: 0 out-segment ix: 4
      Owner: ISIS-SR, Persistent: No, Admin Status: Down, Oper Status: Down
       Out-segment with ix: 4, owner: ISIS-SR, Stale: NO, out intf: eth2, out label: 16007
    Nexthop addr: 10.2.3.2        cross connect ix: 4, op code: Push
 
 
 Non-primary FTN entry with FEC: 1.1.1.7/32, id: 14, row status: Active, Tunnel-Policy: N/A
  Owner: ISIS-SR, distance: 115, Action-type: Redirect to Tunnel, Exp-bits: 0x0, Incoming DSCP: none
  Tunnel id: 0, Protected LSP id: 0, QoS Resource id: 0, Description: N/A, Color: 0
     Cross connect ix: 11, in intf: - in label: 0 out-segment ix: 23
      Owner: ISIS-SR, Persistent: No, Admin Status: Down, Oper Status: Down
       Out-segment with ix: 23, owner: ISIS-SR, Stale: NO, ISIS-SR out intf: eth3, transport out intf: N/A, out label: 16007
    Nexthop addr: 10.2.6.2        cross connect ix: 11, op code: Push and Lookup
 
  bypass_ftn_ix 15
 
P1#
 
 
P1#show mpls ilm-table 1.1.1.7/32
Codes: > - installed ILM, * - selected ILM, p - stale ILM
        K - CLI ILM, T - MPLS-TP, s - Stitched ILM
       S - SNMP, L - LDP, R - RSVP, C - CRLDP
       B - BGP , K - CLI , V - LDP_VC, I - IGP_SHORTCUT
       O - OSPF/OSPF6 SR, i - ISIS SR, k - SR CLI
       P - SR Policy, U - unknown
 
Code    FEC/VRF/L2CKT    ILM-ID      In-Label    Out-Label   In-Intf    Out-Intf/VRF       Nexthop                   LSP-Type
   i>   1.1.1.7/32         40          16007       16007       N/A        eth2              10.2.3.2                  LSP_DEFAULT
   i>   1.1.1.7/32         53          16007       16007       N/A        eth3              10.2.6.2                  LSP_DEFAULT
   P>   1.1.1.7/32         62          25600       16005       N/A        eth3              10.2.6.2                  LSP_DEFAULT
P1#