HPE FlexNetwork HSR6800 Routers Layer 3 IP Routing Configuration Guide Part number:5998-4492r Software version: HSR6800-CMW520-R3303P25 Document version: 6W105-20151231
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Contents IP routing basics 1 Routing table 1 Dynamic routing protocols 2 Route preference 2 Load sharing 3 Route backup 3 Route recursion 3 Route redistribution 3 Displaying and maintaining a routing table 3 Configuring static routing 6 Configuring a static route 6 Configuring BFD for static routes 7 BFD control packet mode 7 BFD echo packet mode 8 Configuring static route FRR 8 Configuration prerequisites 9 Configuration guidelines 9 Configuration procedure 9 Displaying and maintaining static routes 9 Static route configuration examples 10 Basic static route configuration example 10 BFD for static routes configuration example (direct next hop) 12 BFD for static routes configuration example (indirect next hop) 14 Static route FRR configuration example 17 Configuring a default route 19 Configuring RIP 20 Overview 20 RIP route entries 20 RIP timers 20 Routing loop prevention 20 RIP operation 21 RIP versions 21 Supported RIP features 21 Protocols and standards 22 RIP configuration task list 22 Configuring basic RIP 22 Enabling RIP 23 Configuring the interface behavior 23 Configuring a RIP version 23 Configuring RIP route control 24 Configuring an additional routing metric 24 Configuring RIPv2 route summarization 25 Disabling host route reception 26 Advertising a default route 26 Configuring received/redistributed route filtering 27 Configuring a preference for RIP 27 Configuring RIP route redistribution 28 Tuning and optimizing RIP networks 28 Configuration prerequisites 28 Configuring RIP timers 28 Configuring split horizon and poison reverse 29 Configuring the maximum number of ECMP routes 29 Enabling zero field check on incoming RIPv1 messages 30 Enabling source IP address check on incoming RIP updates 30 i
Configuring RIPv2 message authentication 30 Specifying a RIP neighbor 31 Configuring RIP-to-MIB binding 31 Configuring the RIP packet sending rate 31 Configuring RIP FRR 32 Configuring BFD for RIP 33 Enabling single-hop echo detection (for a directly connected RIP neighbor) 33 Configuring single-hop echo detection (for a specific destination) 33 Enabling bidirectional control detection 34 Displaying and maintaining RIP 34 RIP configuration examples 35 Configuring RIP version 35 Configuring RIP route redistribution 36 Configuring an additional metric for a RIP interface 39 Configuring RIP to advertise a summary route 40 Configuring RIP FRR 42 Configuring BFD for RIP (single-hop echo detection) 44 Configure BFD for RIP (single-hop echo detection for a specified destination) 47 Configuring BFD for RIP (bidirectional control detection) 50 Troubleshooting RIP 54 No RIP updates received 54 Route oscillation occurred 54 Configuring OSPF 55 Overview 55 OSPF packets 55 LSA types 55 OSPF area 56 Router types 58 Route types 59 Route calculation 59 OSPF network types 60 DR and BDR 60 Protocols and standards 61 OSPF configuration task list 61 Enabling OSPF 63 Configuration prerequisites 63 Configuration guidelines 63 Configuration procedure 63 Configuring OSPF areas 64 Configuration prerequisites 64 Configuring a stub area 64 Configuring an NSSA area 65 Configuring a virtual link 66 Configuring OSPF network types 66 Configuration prerequisites 67 Configuring the broadcast network type for an interface 67 Configuring the NBMA network type for an interface 67 Configuring the P2MP network type for an interface 68 Configuring the P2P network type for an interface 68 Configuring OSPF route control 69 Configuration prerequisites 69 Configuring OSPF route summarization 69 Configuring OSPF inbound route filtering 70 Configuring ABR Type-3 LSA filtering 70 Configuring an OSPF cost for an interface 71 Configuring the maximum number of ECMP routes 71 Configuring OSPF preference 72 Configuring OSPF route redistribution 72 Advertising a host route 73 Tuning and optimizing OSPF networks 74 Configuration prerequisites 74 ii
Configuring OSPF packet timers 74 Specifying LSA transmission delay 75 Specifying SPF calculation interval 75 Specifying the LSA arrival interval 76 Specifying the LSA generation interval 76 Disabling interfaces from receiving and sending OSPF packets 76 Configuring stub routers 77 Configuring OSPF authentication 77 Adding the interface MTU into DD packets 78 Configuring the maximum number of external LSAs in LSDB 79 Enabling compatibility with RFC 1583 79 Logging neighbor state changes 79 Configuring OSPF network management 79 Enabling message logging 80 Enabling the advertisement and reception of opaque LSAs 80 Configuring OSPF to give priority to receiving and processing hello packets 81 Configuring the LSU transmit rate 81 Enabling OSPF ISPF 81 Configuring OSPF FRR 82 Configuring OSPF GR 83 Configuring the OSPF GR restarter 83 Configuring the OSPF GR helper 84 Triggering OSPF GR 85 Configuring OSPF NSR 85 Configuring BFD for OSPF 86 Configuring control packet bidirectional detection 86 Configuring echo packet single-hop detection 86 Displaying and maintaining OSPF 87 OSPF configuration examples 88 Configuring OSPF basic functions 88 Configuring OSPF route redistribution 91 Configuring OSPF to advertise a summary route 93 Configuring an OSPF stub area 95 Configuring an OSPF NSSA area 98 Configuring OSPF DR election 100 Configuring OSPF virtual links 103 Configuring OSPF GR 105 Configuring OSPF NSR 108 Configuring route filtering 109 Configuring OSPF FRR 112 Configuring BFD for OSPF 114 Troubleshooting OSPF configuration 118 No OSPF neighbor relationship established 118 Incorrect routing information 118 Configuring IS-IS 119 Overview 119 Terminology 119 IS-IS address format 119 NET 120 IS-IS area 121 IS-IS network types 122 IS-IS PDUs 123 Supported IS-IS features 129 Protocols and standards 131 IS-IS configuration task list 132 Configuring IS-IS basic functions 133 Configuration prerequisites 133 Enabling IS-IS 133 Configuring the IS level and circuit level 134 Configuring the network type of an interface as P2P 134 Configuring IS-IS routing information control 135 iii
Configuration prerequisites 135 Configuring IS-IS link cost 135 Specifying a priority for IS-IS 136 Configuring the maximum number of ECMP routes 137 Configuring IS-IS route summarization 137 Advertising a default route 137 Configuring IS-IS route redistribution 138 Configuring IS-IS route filtering 138 Configuring IS-IS route leaking 139 Tuning and optimizing IS-IS networks 139 Configuration prerequisites 139 Specifying intervals for sending IS-IS hello and CSNP packets 140 Specifying the IS-IS hello multiplier 140 Configuring a DIS priority for an interface 140 Disabling an interface from sending/receiving IS-IS packets 141 Disabling hello source address check for a PPP interface 141 Enabling an interface to send small hello packets 141 Configuring LSP parameters 142 Configuring SPF parameters 145 Assigning a high priority to IS-IS routes 145 Setting the LSDB overload bit 146 Configuring system ID to host name mappings 146 Enabling the logging of neighbor state changes 147 Enhancing IS-IS network security 147 Configuration prerequisites 148 Configuring neighbor relationship authentication 148 Configuring area authentication 148 Configuring routing domain authentication 149 Configuring IS-IS GR 149 Configuring IS-IS NSR 150 Configuring IS-IS FRR 150 Enabling IS-IS SNMP trap 151 Binding an IS-IS process with MIBs 152 Configuring BFD for IS-IS 152 Configuring IS-IS MTR 152 Displaying and maintaining IS-IS 154 IS-IS configuration examples 155 IS-IS basic configuration 155 DIS election configuration 159 Configuring IS-IS route redistribution 163 IS-IS GR configuration example 166 IS-IS NSR configuration example 168 IS-IS FRR configuration example 170 IS-IS authentication configuration example 173 Configuring BFD for IS-IS 175 Configuring IS-IS MTR 178 Configuring BGP 184 Overview 184 BGP speaker and BGP peer 184 BGP message types 184 BGP path attributes 184 BGP route selection 189 BGP route advertisement rules 189 BGP load balancing 189 Settlements for problems in large-scale BGP networks 190 MP-BGP 193 Protocols and standards 194 BGP configuration task list 194 Configuring basic BGP 197 Enabling BGP 197 Configuring a BGP peer 197 iv
Configuring a BGP peer group 198 Configuring the BGP dynamic peer feature 201 Specifying the source interface for TCP connections 202 Controlling route generation 203 Configuration prerequisites 203 Injecting a local network 203 Redistributing IGP routes 204 Controlling route distribution and reception 204 Configuring BGP route summarization 204 Advertising a default route to a peer or peer group 205 Configuring BGP route distribution/reception filtering policies 206 Enabling BGP and IGP route synchronization 208 Limiting prefixes received from a peer or peer group 209 Configuring BGP route dampening 210 Controlling BGP path selection 210 Specifying a preferred value for routes received 210 Configuring preferences for BGP routes 211 Configure the default local preference 212 Configuring the MED attribute 212 Configuring the NEXT_HOP attribute 215 Configuring the AS_PATH attribute 216 Tuning and optimizing BGP networks 219 Configuring the BGP keepalive interval and holdtime 219 Configuring the interval for sending the same update 220 Enabling the BGP ORF capability 220 Enabling 4-byte AS number suppression 221 Enabling quick reestablishment of direct EBGP session 222 Enabling MD5 authentication for BGP peers 222 Configuring BGP load balancing 223 Forbidding session establishment with a peer or peer group 223 Configuring GTSM for BGP 224 Disabling BGP route advertisement to a peer or peer group 225 Configuring BGP soft-reset 225 Disabling BGP routing policies from automatically taking effect 226 Configuring a large scale BGP network 227 Configuration prerequisites 227 Configuring BGP community 227 Configuring a BGP route reflector 228 Configuring a BGP confederation 229 Configuring BGP GR 230 Configuring BGP NSR 231 Enabling trap 232 Enabling logging of session state changes 232 Configuring BFD for BGP 232 Displaying and maintaining BGP 233 Displaying BGP 233 Resetting BGP session 235 Clearing BGP information 235 BGP configuration examples 235 BGP basic configuration 235 BGP and IGP synchronization configuration 239 BGP load balancing configuration 242 BGP route summarization configuration 244 BGP community configuration 247 BGP route reflector configuration 250 BGP confederation configuration 251 BGP path selection configuration 255 BGP GR configuration 258 BFD for BGP configuration 259 BGP dynamic peer configuration 263 Troubleshooting BGP 265 BGP peer relationship not established 265 v
Configuring policy-based routing 266 Overview 266 Policy 266 PBR and track 268 PBR configuration task list 268 Configuring a policy 268 Creating a node 268 Configuring match criteria for a node 268 Configuring actions for a node 269 Configuring PBR 270 Configuring local PBR 270 Configuring interface PBR 270 Displaying and maintaining PBR 271 PBR configuration examples 272 Configuring local PBR based on packet type 272 Configuring interface PBR based on packet type 273 Configuring interface PBR based on packet length 274 Configuring interface PBR based on reverse input interface 277 Configuring interface PBR on a VLAN interface 279 Configuring IPv6 static routing 281 Overview 281 Configuring IPv6 static routing 281 Displaying and maintaining IPv6 static routes 282 IPv6 static routing configuration example 282 Network requirements 282 Configuration procedure 282 Configuring an IPv6 default route 285 Configuring RIPng 286 Overview 286 RIPng working mechanism 286 RIPng packet format 286 RIPng packet processing procedure 287 Protocols and standards 288 RIPng configuration task list 288 Configuring RIPng basic functions 288 Configuration prerequisites 289 Configuration procedure 289 Configuring RIPng route control 289 Configuring an additional routing metric 289 Configuring RIPng route summarization 290 Advertising a default route 290 Configuring a RIPng route filtering policy 290 Configuring a priority for RIPng 291 Configuring RIPng route redistribution 291 Tuning and optimizing the RIPng network 291 Configuring RIPng timers 291 Configuring split horizon and poison reverse 292 Configuring zero field check on RIPng packets 293 Configuring the maximum number of ECMP routes 293 Applying IPsec policies for RIPng 293 Displaying and maintaining RIPng 294 RIPng configuration examples 295 Configuring RIPng basic functions 295 Configuring RIPng route redistribution 297 Configuring RIPng IPsec policies 299 Configuring OSPFv3 302 Overview 302 vi
Packets 302 LSA types 302 Timers 303 Supported features 304 Protocols and standards 304 OSPFv3 configuration task list 304 Enabling OSPFv3 305 Configuration prerequisites 305 Enabling OSPFv3 305 Configuring OSPFv3 area parameters 306 Configuration prerequisites 306 Configuring an OSPFv3 stub area 306 Configuring an OSPFv3 NSSA area 306 Configuring an OSPFv3 virtual link 307 Configuring OSPFv3 network types 307 Configuration prerequisites 308 Configuring the OSPFv3 network type for an interface 308 Configuring an NBMA or P2MP neighbor 308 Configuring OSPFv3 routing information control 308 Configuration prerequisites 308 Configuring OSPFv3 route summarization 308 Configuring OSPFv3 inbound route filtering 309 Configuring an OSPFv3 cost for an interface 309 Configuring the maximum number of OSPFv3 ECMP routes 310 Configuring a priority for OSPFv3 310 Configuring OSPFv3 route redistribution 310 Tuning and optimizing OSPFv3 networks 311 Configuration prerequisites 311 Configuring OSPFv3 timers 312 Configuring a DR priority for an interface 312 Ignoring MTU check for DD packets 313 Disabling interfaces from receiving and sending OSPFv3 packets 313 Enabling the logging of neighbor state changes 313 Configuring OSPFv3 GR 314 Configuring GR restarter 314 Configuring GR helper 314 Configuring BFD for OSPFv3 315 Applying IPsec policies for OSPFv3 315 Displaying and maintaining OSPFv3 317 OSPFv3 configuration examples 318 Configuring OSPFv3 areas 318 Configuring OSPFv3 DR election 322 Configuring OSPFv3 route redistribution 324 Configuring OSPFv3 GR 327 Configuring BFD for OSPFv3 329 Configuring OSPFv3 IPsec policies 332 Troubleshooting OSPFv3 configuration 335 No OSPFv3 neighbor relationship established 335 Incorrect routing information 335 Configuring IPv6 IS-IS 337 Overview 337 Configuring basic IPv6 IS-IS 337 Configuration prerequisites 337 Configuration procedure 337 Configuring IPv6 IS-IS route control 338 Configuring BFD for IPv6 IS-IS 339 Configuring IPv6 IS-IS MTR 339 Displaying and maintaining IPv6 IS-IS 340 IPv6 IS-IS configuration examples 341 IPv6 IS-IS basic configuration example 341 Configuring BFD for IPv6 IS-IS 346 vii
Configuring IPv6 IS-IS MTR 349 Configuring IPv6 BGP 352 IPv6 BGP overview 352 IPv6 BGP configuration task list 352 Configuring IPv6 BGP basic functions 353 Configuration prerequisites 353 Specifying an IPv6 BGP peer 353 Injecting a local IPv6 route 354 Configuring a preferred value for routes from a peer or peer group 354 Specifying the source interface for establishing TCP connections 355 Allowing the establishment of an indirect EBGP connection 355 Configuring a description for an IPv6 peer or peer group 355 Disabling session establishment to an IPv6 peer or peer group 356 Logging IPv6 peer or peer group state changes 356 Controlling route distribution and reception 356 Configuration prerequisites 357 Configuring IPv6 BGP route redistribution 357 Configuring IPv6 BGP route summarization 357 Advertising a default route to an IPv6 peer or peer group 357 Configuring outbound route filtering 358 Configuring inbound route filtering 359 Configuring IPv6 BGP and IGP route synchronization 359 Configuring route dampening 360 Configuring IPv6 BGP route attributes 360 Configuration prerequisites 360 Configuring IPv6 BGP preference and default LOCAL_PREF and NEXT_HOP attributes 360 Configuring the MED attribute 361 Configuring the AS_PATH attribute 362 Tuning and optimizing IPv6 BGP networks 362 Configuration prerequisites 363 Configuring IPv6 BGP timers 363 Configuring IPv6 BGP soft reset 363 Enabling the IPv6 BGP ORF capability 364 Enabling 4-byte AS number suppression 365 Configuring the maximum number of ECMP routes 366 Enabling MD5 authentication for TCP connections 366 Applying an IPsec policy to an IPv6 BGP peer or peer group 366 Configuring GTSM for IPv6 BGP 367 Configuring a large-scale IPv6 BGP network 368 Configuration prerequisites 368 Configuring IPv6 BGP peer group 368 Configuring IPv6 BGP community 369 Configuring an IPv6 BGP route reflector 370 Configuring 6PE 371 Configuration prerequisites 371 Configuring basic 6PE capabilities 371 Configuring optional 6PE capabilities 372 Configuring BFD for IPv6 BGP 373 Displaying and maintaining IPv6 BGP 374 Displaying BGP 374 Resetting IPv6 BGP connections 375 Clearing IPv6 BGP information 375 IPv6 BGP configuration examples 376 IPv6 BGP basic configuration 376 IPv6 BGP route reflector configuration 378 6PE configuration 379 IPv6 BGP IPsec policy configuration 383 Configuring BFD for IPv6 BGP 388 Configuring IPv6 policy-based routing 393 Introduction to IPv6 policy-based routing 393 viii
What is policy-based routing 393 Policy 393 IPv6 PBR configuration task list 394 Configuring an IPv6 policy 395 Creating an IPv6 node 395 Configuring match criteria for an IPv6 node 395 Defining the actions for an IPv6 node 395 Configuring IPv6 PBR 396 Configuring IPv6 local PBR 396 Configuring IPv6 interface PBR 396 Displaying and maintaining IPv6 PBR configuration 397 IPv6 PBR configuration examples 398 Configuring IPv6 local PBR based on packet type 398 Configuring IPv6 interface PBR based on packet type 399 Configuring IPv6 interface PBR based on packet length 401 Configuring routing policies 405 Overview 405 Filters 405 Configuring filters 406 Configuration prerequisites 406 Configuring an IP-prefix list 406 Configuring an AS path list 407 Configuring a community list 407 Configuring an extended community list 408 Configuring a routing policy 408 Configuration prerequisites 408 Creating a routing policy 408 Configuring if-match clauses 408 Configuring apply clauses 410 Configuring a continue clause 411 Displaying and maintaining the routing policy 412 Routing policy configuration examples 412 Applying a routing policy to IPv4 route redistribution 412 Applying a routing policy to IPv6 route redistribution 415 Applying a routing policy to filter received BGP routes 417 Troubleshooting routing policy configuration 419 IPv4 routing information filtering failure 419 IPv6 routing information filtering failure 419 Configuring QoS policy routing 420 Overview 420 Configuring QoS policy routing 420 Configuring a QoS policy 420 Applying the QoS policy 420 QoS policy routing configuration examples 421 IPv4 QoS policy routing configuration example 421 IPv6 QoS policy routing configuration example 422 Configuring MTR 424 MTR overview 424 Work mechanism 424 Supported features 424 Configuring MTR 424 Displaying and maintaining MTR 425 Document conventions and icons 426 Conventions 426 Network topology icons 427 Support and other resources 428 Accessing Hewlett Packard Enterprise Support 428 ix
Accessing updates 428 Websites 429 Customer self repair 429 Remote support 429 Documentation feedback 429 Index 431 x
IP routing basics IP routing directs the forwarding of IP packets on routers based on a routing table. This book focuses on unicast routing protocols. For more information about multicast routing protocols, see IP Multicast Configuration Guide. Routing table A router maintains at least two routing tables: one global routing table and one forwarding information base (FIB). The FIB table contains only the optimal routes, and the global routing table contains all routes. The router uses the FIB table to forward packets. For more information about the FIB table, see Layer 3 IP Services Configuration Guide. Routes can be classified by different criteria, as shown in Table 1. Table 1 Categories of routes Criterion Destination Whether the destination is directly connected Origin Categories Network route Destination is a network. The subnet mask is less than 32 bits. Host route Destination is a host. The subnet mask is 32 bits. Direct route Destination is directly connected. Indirect route Destination is indirectly connected. Direct route A direct route is discovered by the data link protocol on an interface, and is also called an "interface route." Static route A static route is manually configured by an administrator. Dynamic route A dynamic route is dynamically discovered by a routing protocol. Static routes are easy to configure and require less system resources. They work well in small and stable networks. In networks where topology changes might occur frequently, using a dynamic routing protocol is better. To view brief information about a routing table, use the display ip routing-table command, as shown in the following example: <Sysname> display ip routing-table Routing Tables: Public Destinations : 7 Routes : 7 Destination/Mask Proto Pre Cost NextHop Interface 1.1.1.0/24 Direct 0 0 1.1.1.1 Eth1/1 2.2.2.0/24 Static 60 0 12.2.2.2 Eth1/2 80.1.1.0/24 OSPF 10 2 80.1.1.1 Eth1/3 (Part of the output information is not shown) A route entry includes the following key items: Destination IP address of the destination host or network. Mask Mask length of the IP address. 1
Pre Preference of the route. Among routes to the same destination, the one with the highest preference is optimal. Cost When multiple routes to a destination have the same preference, the one with the smallest cost becomes the optimal route. NextHop Next hop. Interface Output interface. Dynamic routing protocols Dynamic routing protocols dynamically collect and report reachability information to adapt to topology changes. They are suitable for large networks. Compared with static routing, dynamic routing protocols require more resources, and are complicated to configure. Dynamic routing protocols can be classified by different criteria, as shown in Table 2: Table 2 Categories of dynamic routing protocols Criterion Optional scope Routing algorithm Destination address type IP version Categories Interior gateway protocols (IGPs) Work within an autonomous system (AS). Examples include RIP, OSPF, and IS-IS. Exterior gateway protocols (EGPs) Work between ASs. The most popular one is BGP. Distance-vector protocols RIP and BGP. BGP is also considered a path-vector protocol. Link-state protocols OSPF and IS-IS. Unicast routing protocols RIP, OSPF, BGP, and IS-IS. Multicast routing protocols PIM-SM and PIM-DM (For more information, see IP Multicast Configuration Guide). IPv4 routing protocols RIP, OSPF, BGP, and IS-IS. IPv6 routing protocols RIPng, OSPFv3, IPv6 BGP, and IPv6 IS-IS. NOTE: An AS refers to a group of routers that use the same routing policy and work under the same administration. Route preference Routing protocols (including static and direct routing) each by default have a preference. If they find multiple routes to the same destination, the router selects the route with the highest preference as the optimal route. The preference of a direct route is always 0 and cannot be changed. You can configure a preference for each static route and each dynamic routing protocol as required. The following table lists the route types and their default preferences. The smaller the value, the higher the preference. Table 3 Route types and their default route preferences Routing type Preference Direct route 0 OSPF 10 2
Routing type Preference IS-IS 15 Static route 60 RIP 100 OSPF ASE 150 OSPF NSSA 150 IBGP 255 EBGP 255 Unknown (route from an untrusted source) 256 Load sharing A routing protocol might find multiple optimal equal-cost routes to the same destination. You can use these routes to implement equal-cost multi-path (ECMP) load sharing. Static routing, IPv6 static routing, RIP/RIPng, OSPF/OSPFv3, BGP/IPv6 BGP, and IS-IS/IPv6 IS-IS support ECMP load sharing. Route backup Route backup can improve network availability. Among multiple routes to the same destination, the route with the highest priority is the main route and others are backup routes. The router forwards matching packets through the main route. When the main route fails, the route with the highest preference among the backup routes is selected to forward packets. When the main route recovers, the router uses it to forward packets. Route recursion To use a BGP, static, or RIP route that has an indirectly-connected next hop, a router must perform route recursion to find the outgoing interface to reach the next hop. Link-state routing protocols, such as OSPF and IS-IS, do not need route recursion, because they obtain directly-connected next hops through route calculation. Route redistribution Route redistribution enables routing protocols to learn route information from each other. A dynamic routing protocol can redistribute routes from other routing protocols including direct and static routing. For more information, see the respective chapters on those routing protocols in this configuration guide. Displaying and maintaining a routing table 3
Task Command Remarks Display the routing table. Display routes matching an IPv4 basic ACL. Display routes to the specified destination. Display routes with destination addresses in the specified range. Display routing information matching an IPv4 prefix list. Display the routes of a routing protocol. Display statistics about the routing table. Clear statistics for the routing table. Display IPv6 routing table information. Display routes matching an IPv6 ACL. display ip routing-table [ multiple-topology topology-name vpn-instance vpn-instance-name ] [ verbose ] [ { begin exclude include } regular-expression ] display ip routing-table [ multiple-topology topology-name vpn-instance vpn-instance-name ] acl acl-number [ verbose ] [ { begin exclude include } regular-expression ] display ip routing-table [ multiple-topology topology-name vpn-instance vpn-instance-name ] ip-address [ mask mask-length ] [ longer-match ] [ verbose ] [ { begin exclude include } regular-expression ] display ip routing-table [ multiple-topology topology-name vpn-instance vpn-instance-name ] ip-address1 { mask mask-length } ip-address2 { mask mask-length } [ verbose ] [ { begin exclude include } regular-expression ] display ip routing-table [ multiple-topology topology-name vpn-instance vpn-instance-name ] ip-prefix ip-prefix-name [ verbose ] [ { begin exclude include } regular-expression ] display ip routing-table [ multiple-topology topology-name vpn-instance vpn-instance-name ] protocol protocol [ inactive verbose ] [ { begin exclude include } regular-expression ] [ { begin exclude include } regular-expression ] [ { begin exclude include } regular-expression ] display ip routing-table [ multiple-topology topology-name vpn-instance vpn-instance-name ] statistics [ { begin exclude include } regular-expression ] reset ip routing-table statistics protocol [ multiple-topology topology-name vpn-instance vpn-instance-name ] { protocol all } display ipv6 routing-table [ vpn-instance vpn-instance-name ] [ verbose ] [ { begin exclude include } regular-expression ] display ipv6 routing-table [ vpn-instance vpn-instance-name ] acl acl6-number [ verbose ] [ { begin exclude include } regular-expression ] Available in any view. Available in any view. Available in any view. Available in any view. Available in any view. Available in any view. Available in any view. Available in user view. Available in any view. Available in any view. 4
Task Command Remarks Display routing information for a specified destination IPv6 address. Display IPv6 routes with destination addresses in an IPv6 address range. Display routing information permitted by an IPv6 prefix list. Display routes of an IPv6 routing protocol. Display IPv6 routing statistics. Clear specified IPv6 routing statistics. display ipv6 routing-table [ vpn-instance vpn-instance-name ] ipv6-address [ prefix-length ] [ longer-match ] [ verbose ] [ { begin exclude include } regular-expression ] display ipv6 routing-table [ vpn-instance vpn-instance-name ] ipv6-address1 prefix-length1 ipv6-address2 prefix-length2 [ verbose ] [ { begin exclude include } regular-expression ] display ipv6 routing-table [ vpn-instance vpn-instance-name ] ipv6-prefix ipv6-prefix-name [ verbose ] [ { begin exclude include } regular-expression ] display ipv6 routing-table [ vpn-instance vpn-instance-name ] protocol protocol [ inactive verbose ] [ { begin exclude include } regular-expression ] display ipv6 routing-table [ vpn-instance vpn-instance-name ] statistics [ { begin exclude include } regular-expression ] reset ipv6 routing-table statistics protocol [ vpn-instance vpn-instance-name ] { protocol all } Available in any view. Available in any view. Available in any view. Available in any view. Available in any view. Available in user view. 5
Configuring static routing Static routes are manually configured. If a network's topology is simple, you only need to configure static routes for the network to work correctly. Static routes cannot adapt to network topology changes. If a fault or a topological change occurs in the network, the network administrator must modify the static routes manually. Configuring a static route Before you configure a static route, complete the following tasks: Configure physical parameters for related interfaces. Configure link-layer attributes for related interfaces. Configure IP addresses for related interfaces. Follow these guidelines when you configure a static route: The next hop address of a static route cannot be the IP address of a local interface. You can associate a track entry with a static route to monitor the reachability of the next hops. For more information about track, see High Availability Configuration Guide. The device supports VPN instances and MTR for static routes. For information about specifying VPN instances for static routes, see MPLS Configuration Guide. For information about configuring static route MTR, see "Configuring MTR." To configure a static route: 2. Configure a static route. Method 1: ip route-static dest-address { mask mask-length } { next-hop-address [ track track-entry-number ] interface-type interface-number [ next-hop-address ] vpn-instance d-vpn-instance-name next-hop-address [ track track-entry-number ] } [ preference preference-value ] [ tag tag-value ] [ permanent ] [ description description-text ] Method 2: ip route-static vpn-instance s-vpn-instance-name&<1-6> dest-address { mask mask-length } { next-hop-address [ public ] [ track track-entry-number ] interface-type interface-number [ next-hop-address ] vpn-instance d-vpn-instance-name next-hop-address [ track track-entry-number ] } [ preference preference-value ] [ tag tag-value ] [ permanent ] [ description description-text ] Method 3: ip route-static multiple-topology topology-name dest-address { mask mask-length } { next-hop-address interface-type interface-number [ next-hop-address ] } [ preference preference-value ] [ tag tag-value ] [ description description-text ] Use one of the methods. By default, no static route is configured. 6
3. Configure the default preference for static routes. 4. Delete all static routes, including the default route. ip route-static default-preference default-preference-value delete [ multiple-topology topology-name vpn-instance vpn-instance-name ] static-routes all 60 by default. Configuring BFD for static routes Bidirectional forwarding detection (BFD) provides a general-purpose, standard, medium-, and protocol-independent fast failure detection mechanism. It can uniformly and quickly detect the failures of the bidirectional forwarding paths between two routers for protocols, such as routing protocols and MPLS. For more information about BFD, see High Availability Configuration Guide. BFD control packet mode To use BFD control packets for bidirectional detection between two devices, enable BFD control packet mode on each device for the static route destined to the peer. To configure a static route and enable BFD control packet mode for it, specify an outgoing interface and a direct next hop, or specify an indirect next hop and a specific BFD packet source address for the static route. To configure a static route with BFD control packet mode enabled (direct next hop): 5. Enter system view. system-view N/A 6. Configure a static route and enable BFD control packet mode for it. Method 1: ip route-static dest-address { mask mask-length } interface-type interface-number next-hop-address bfd control-packet [ preference preference-value ] [ tag tag-value ] [ description description-text ] Method 2: ip route-static vpn-instance s-vpn-instance-name&<1-6> dest-address { mask mask-length } interface-type interface-number next-hop-address bfd control-packet [ preference preference-value ] [ tag tag-value ] [ description description-text ] To configure a static route with BFD control packet mode enabled (indirect next hop): Use either method. 7
2. Configure a static route and enable BFD control packet mode for it. Method 1: ip route-static dest-address { mask mask-length } next-hop-address bfd control-packet bfd-source ip-address [ preference preference-value ] [ tag tag-value ] [ description description-text ] Method 2: ip route-static vpn-instance s-vpn-instance-name&<1-6> dest-address { mask mask-length } next-hop-address bfd control-packet bfd-source ip-address [ preference preference-value ] [ tag tag-value ] [ description description-text ] Use either method. BFD echo packet mode With BFD echo packet mode enabled for a static route, the outgoing interface sends BFD echo packets to the destination device, which loops the packets back to test the link reachability. IMPORTANT: Enabling BFD for a flapping route could worsen the situation. Do not use BFD for a static route with the outgoing interface in spoofing state. To configure BFD echo packet mode for static routes: 2. Configure the source address of echo packets. 3. Enable BFD echo packet mode for static routes. bfd echo-source-ip ip-address Method 1: ip route-static dest-address { mask mask-length } interface-type interface-number next-hop-address bfd echo-packet [ preference preference-value ] [ tag tag-value ] [ description description-text ] Method 2: ip route-static vpn-instance s-vpn-instance-name&<1-6> dest-address { mask mask-length } interface-type interface-number next-hop-address bfd echo-packet [ preference preference-value ] [ tag tag-value ] [ description description-text ] Not configured by default. For more information about this command, see High Availability Command Reference. Use either method. Configuring static route FRR A link or router failure on a path can cause packet loss and even routing loop. Static route fast reroute (FRR) enables fast rerouting to minimize the impact of link or node failures. 8
Figure 1 Network diagram for static route FRR As shown in Figure 1, upon a link failure, FRR designates a backup next hop by using a routing policy for routes matching the specified criteria. Packets are directed to the backup next hop to avoid traffic interruption. Configuration prerequisites Create a routing policy to be referenced by FRR and use the apply fast-reroute backup-interface command to specify a backup next hop in the routing policy. For more information about the command and routing policy configurations, see "Configuring routing policies." Configuration guidelines FRR takes effect only for static routes that have both an outgoing interface and next hop. Do not use FRR and BFD at the same time. Configuration procedure To configure static route FRR: 2. Configure the source address of BFD echo packets. 3. Configure static route FRR. bfd echo-source-ip ip-address ip route-static [ vpn-instance vpn-instance-name ] fast-reroute route-policy route-policy-name Not configured by default. For more information about this command, see High Availability Command Reference. Not configured by default. Displaying and maintaining static routes Task Command Remarks Display information of static routes. display ip routing-table protocol static [ inactive verbose ] [ { begin exclude include } regular-expression ] Available in any view. For more information about this command, see Layer 3 IP Routing Command Reference. 9
Static route configuration examples Basic static route configuration example Network requirements Configure static routes in Figure 2 for interconnections between any two hosts. Figure 2 Network diagram Host B 1.1.6.2/24 GE2/1/3 1.1.6.1/24 GE2/1/1 GE2/1/2 1.1.4.2/30 1.1.5.5/30 Router B GE2/1/2 1.1.4.1/30 GE2/1/2 1.1.5.6/30 Host A 1.1.2.2/24 GE2/1/1 1.1.2.3/24 Router A GE2/1/1 1.1.3.1/24 Router C Host C 1.1.3.2/24 Configuration procedure 1. Configure IP addresses for interfaces. (Details not shown.) 2. Configure static routes: # Configure a default route on Router A. <RouterA> system-view [RouterA] ip route-static 0.0.0.0 0.0.0.0 1.1.4.2 # Configure two static routes on Router B. <RouterB> system-view [RouterB] ip route-static 1.1.2.0 255.255.255.0 1.1.4.1 [RouterB] ip route-static 1.1.3.0 255.255.255.0 1.1.5.6 # Configure a default route on Router C. <RouterC> system-view [RouterC] ip route-static 0.0.0.0 0.0.0.0 1.1.5.5 3. Configure the hosts: Configure the default gateways of Host A, Host B, and Host C as 1.1.2.3, 1.1.6.1, and 1.1.3.1, respectively. (Details not shown.) 4. Verify the configuration: # Display the IP routing table of Router A. [RouterA] display ip routing-table Routing Tables: Public Destinations : 7 Routes : 7 Destination/Mask Proto Pre Cost NextHop Interface 0.0.0.0/0 Static 60 0 1.1.4.2 GE2/1/2 10
1.1.2.0/24 Direct 0 0 1.1.2.3 GE2/1/1 1.1.2.3/32 Direct 0 0 127.0.0.1 InLoop0 1.1.4.0/30 Direct 0 0 1.1.4.1 GE2/1/2 1.1.4.1/32 Direct 0 0 127.0.0.1 InLoop0 127.0.0.0/8 Direct 0 0 127.0.0.1 InLoop0 127.0.0.1/32 Direct 0 0 127.0.0.1 InLoop0 # Display the IP routing table of Router B. [RouterB] display ip routing-table Routing Tables: Public Destinations : 10 Routes : 10 Destination/Mask Proto Pre Cost NextHop Interface 1.1.2.0/24 Static 60 0 1.1.4.1 GE2/1/1 1.1.3.0/24 Static 60 0 1.1.5.6 GE2/1/2 1.1.4.0/30 Direct 0 0 1.1.4.2 GE2/1/1 1.1.4.2/32 Direct 0 0 127.0.0.1 InLoop0 1.1.5.0/30 Direct 0 0 1.1.5.5 GE2/1/2 1.1.5.5/32 Direct 0 0 127.0.0.1 InLoop0 127.0.0.0/8 Direct 0 0 127.0.0.1 InLoop0 127.0.0.1/32 Direct 0 0 127.0.0.1 InLoop0 1.1.6.0/24 Direct 0 0 1.1.6.1 GE2/1/3 1.1.6.1/32 Direct 0 0 127.0.0.1 InLoop0 # Use the ping command on Host B to test the reachability of Host A (Windows XP runs on the two hosts). C:\Documents and Settings\Administrator>ping 1.1.2.2 Pinging 1.1.2.2 with 32 bytes of data: Reply from 1.1.2.2: bytes=32 time=1ms TTL=126 Reply from 1.1.2.2: bytes=32 time=1ms TTL=126 Reply from 1.1.2.2: bytes=32 time=1ms TTL=126 Reply from 1.1.2.2: bytes=32 time=1ms TTL=126 Ping statistics for 1.1.2.2: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milli-seconds: Minimum = 1ms, Maximum = 1ms, Average = 1ms # Use the tracert command on Host B to test the reachability of Host A. C:\Documents and Settings\Administrator>tracert 1.1.2.2 Tracing route to 1.1.2.2 over a maximum of 30 hops 1 <1 ms <1 ms <1 ms 1.1.6.1 2 <1 ms <1 ms <1 ms 1.1.4.1 3 1 ms <1 ms <1 ms 1.1.2.2 Trace complete 11
BFD for static routes configuration example (direct next hop) Network requirements In Figure 3, configure a static route to subnet 120.1.1.0/24 on Router A, configure a static route to subnet 121.1.1.0/24 on Router B, and enable BFD for both routes. Configure a static route to subnet 120.1.1.0/24 and a static route to subnet 121.1.1.0/24 on Router C. When the link between Router A and Router B through the Layer 2 switch fails, BFD can detect the failure immediately and inform Router A and Router B to communicate through Router C. Figure 3 Network diagram Device Interface IP address Device Interface IP address Router A GE2/1/1 12.1.1.1/24 Router B GE2/1/1 12.1.1.2/24 GE2/1/2 10.1.1.102/24 GE2/1/2 13.1.1.1/24 Router C GE2/1/1 10.1.1.100/24 GE2/1/2 13.1.1.2/24 Configuration procedure 1. Configure IP addresses for the interfaces. (Details not shown.) 2. Configure static routes and BFD: # Configure static routes on Router A and enable BFD control packet mode for the static route through the Layer 2 switch. <RouterA> system-view [RouterA] interface GigabitEthernet 2/1/1 [RouterA-GigabitEthernet2/1/1] bfd min-transmit-interval 500 [RouterA-GigabitEthernet2/1/1] bfd min-receive-interval 500 [RouterA-GigabitEthernet2/1/1] bfd detect-multiplier 9 [RouterA-GigabitEthernet2/1/1] quit [RouterA] ip route-static 120.1.1.0 24 GigabitEthernet 2/1/1 12.1.1.2 bfd control-packet [RouterA] ip route-static 120.1.1.0 24 GigabitEthernet 2/1/2 10.1.1.100 preference 65 [RouterA] quit # Configure static routes on Router B and enable BFD control packet mode for the static route through the Layer 2 switch. <RouterB> system-view [RouterB] interface GigabitEthernet 2/1/1 [RouterB-GigabitEthernet2/1/1] bfd min-transmit-interval 500 [RouterB-GigabitEthernet2/1/1] bfd min-receive-interval 500 [RouterB-GigabitEthernet2/1/1] bfd detect-multiplier 9 [RouterB-GigabitEthernet2/1/1] quit 12
[RouterB] ip route-static 121.1.1.0 24 GigabitEthernet 2/1/1 12.1.1.1 bfd control-packet [RouterB] ip route-static 121.1.1.0 24 GigabitEthernet 2/1/2 13.1.1.2 preference 65 [RouterB] quit # Configure static routes on Router C. <RouterC> system-view [RouterC] ip route-static 120.1.1.0 24 GigabitEthernet 2/1/2 13.1.1.1 [RouterC] ip route-static 121.1.1.0 24 GigabitEthernet 2/1/1 10.1.1.102 3. Verify the configuration: # Display BFD sessions on Router A. <RouterA> display bfd session Total Session Num: 1 Init Mode: Active Session Working Under Ctrl Mode: LD/RD SourceAddr DestAddr State Holdtime Interface 4/7 12.1.1.1 12.1.1.2 Up 2000ms GigabitEthernet2/1/1 The output shows that the BFD session has been created. # Display static routes on Router A. The static route to Router B through the Layer 2 switch is displayed in the output. <RouterA> display ip routing-table protocol static Public Routing Table : Static Summary Count : 2 Static Routing table Status : <Active> Summary Count : 1 Destination/Mask Proto Pre Cost NextHop Interface 120.1.1.0/24 Static 60 0 12.1.1.2 GE2/1/1 Direct Routing table Status : <Inactive> Summary Count : 1 Destination/Mask Proto Pre Cost NextHop Interface 120.1.1.0/24 Static 65 0 10.1.1.100 GE2/1/2 # Enable BFD debugging. When the link between Router A and the switch fails, Router A can detect the failure. <RouterA> debugging bfd event <RouterA> debugging bfd scm <RouterA> terminal debugging %Jul 27 10:18:18:672 2007 RouterA BFD/4/LOG:Sess[12.1.1.1/12.1.1.2, GigabitEthernet2/1/1,Ctrl], Sta: UP->DOWN, Diag: 1 *Jul 27 10:18:18:672 2007 RouterA BFD/7/EVENT:Send sess-down Msg, [Src:12.1.1.1,Dst:12.1.1.2,GigabitEthernet2/1/1,Ctrl], instance:0, protocol:static *Jul 27 10:18:19:172 2007 RouterA BFD/7/EVENT:Receive Delete-sess, [Src:12.1.1.1,Dst:12.1.1.2,GigabitEthernet2/1/1,Ctrl], Direct, Instance:0x0, Proto:STATIC #*Jul 27 10:18:19:172 2007 RouterA BFD/7/EVENT:Notify driver to stop receiving bf 13
# Display the static route information again. Router A communicates with Router B over the static route passing Router C now. <RouterA> display ip routing-table protocol static Public Routing Table : Static Summary Count : 2 Static Routing table Status : <Active> Summary Count : 1 Destination/Mask Proto Pre Cost NextHop Interface 120.1.1.0/24 Static 65 0 10.1.1.100 GE2/1/2 Static Routing table Status : < Inactive> Summary Count : 1 Destination/Mask Proto Pre Cost NextHop Interface 120.1.1.0/24 Static 60 0 12.1.1.2 GE2/1/1 BFD for static routes configuration example (indirect next hop) Network requirements In Figure 4, Router A has a route to interface Loopback 1 (2.2.2.9/32) on Router B, with the outgoing interface GigabitEthernet 2/1/1. Router B has a route to interface Loopback 1 (1.1.1.9/32) on Router A, with the outgoing interface GigabitEthernet 2/1/1. Router D has a route to 1.1.1.9/32, with the outgoing interface GigabitEthernet 2/1/1, and a route to 2.2.2.9/32, with the outgoing interface GigabitEthernet 2/1/2. Configure a static route to subnet 120.1.1.0/24 on Router A, configure a static route to subnet 121.1.1.0/24 on Router B, and enable BFD for both routes. Configure a static route to subnet 120.1.1.0/24 and a static route to subnet 121.1.1.0/24 on both Router C and Router D. When the link between Router A and Router B through Router D fails, BFD can detect the failure immediately and Router A and Router B can communicate through Router C. Figure 4 Network diagram Device Interface IP address Device Interface IP address Router A GE2/1/1 12.1.1.1/24 Router B GE2/1/1 11.1.1.2/24 GE2/1/2 10.1.1.102/24 GE2/1/2 13.1.1.1/24 Loop1 1.1.1.9/32 Loop1 2.2.2.9/32 Router C GE2/1/1 10.1.1.100/24 Router D GE2/1/1 12.1.1.2/24 GE2/1/2 13.1.1.2/24 GE2/1/2 11.1.1.1/24 14
Configuration procedure 1. Configure IP addresses for the interfaces. (Details not shown.) 2. Configure static routes and BFD: # Configure static routes on Router A and enable BFD control packet mode for the static route through Router D. <RouterA> system-view [RouterA] interface loopback 1 [RouterA-LoopBack1] bfd min-transmit-interval 500 [RouterA-LoopBack1] bfd min-receive-interval 500 [RouterA-LoopBack1] bfd detect-multiplier 9 [RouterA-LoopBack1] quit [RouterA] ip route-static 120.1.1.0 24 2.2.2.9 bfd control-packet bfd-source 1.1.1.9 [RouterA] ip route-static 120.1.1.0 24 GigabitEthernet 2/1/2 10.1.1.100 preference 65 [RouterA] quit # Configure static routes on Router B and enable BFD control packet mode for the static route through Router D. <RouterB> system-view [RouterB] interface loopback 1 [RouterB-LoopBack1] bfd min-transmit-interval 500 [RouterB-LoopBack1] bfd min-receive-interval 500 [RouterB-LoopBack1] bfd detect-multiplier 9 [RouterB-LoopBack1] quit [RouterB] ip route-static 121.1.1.0 24 1.1.1.9 bfd control-packet bfd-source 2.2.2.9 [RouterB] ip route-static 121.1.1.0 24 GigabitEthernet 2/1/2 13.1.1.2 preference 65 [RouterB] quit # Configure static routes on Router C. <RouterC> system-view [RouterC] ip route-static 120.1.1.0 24 GigabitEthernet 2/1/2 13.1.1.1 [RouterC] ip route-static 121.1.1.0 24 GigabitEthernet 2/1/1 10.1.1.102 # Configure static routes on Router D. <RouterD> system-view [RouterD] ip route-static 120.1.1.0 24 GigabitEthernet 2/1/2 11.1.1.2 [RouterD] ip route-static 121.1.1.0 24 GigabitEthernet 2/1/1 12.1.1.1 3. Verify the configuration: The following operations are performed on Router A. The operations on Router B are similar. # Display the BFD session information. <RouterA> display bfd session Total Session Num: 1 Init Mode: Active Session Working Under Ctrl Mode: LD/RD SourceAddr DestAddr State Holdtime Interface 4/7 1.1.1.9 2.2.2.9 Up 2000ms Loop1 # Display the static route information on Router A. <RouterA> display ip routing-table protocol static Public Routing Table : Static 15
Summary Count : 2 Static Routing table Status : <Active> Summary Count : 1 Destination/Mask Proto Pre Cost NextHop Interface 120.1.1.0/24 Static 60 0 2.2.2.9 GE2/1/1 Static Routing table Status : <Inactive> Summary Count : 1 Destination/Mask Proto Pre Cost NextHop Interface 120.1.1.0/24 Static 65 0 10.1.1.100 GE2/1/2 # Enable BFD debugging. When the link between Router A and Router D fails, Router A can detect the failure. <RouterA> debugging bfd event <RouterA> debugging bfd scm <RouterA> terminal debugging %Oct 10 10:18:18:672 2010 RouterA BFD/4/LOG:Sess[1.1.1.9/2.2.2.9, Loop1,Ctrl], Sta: UP->DOWN, Diag: 1 *Oct 10 10:18:18:672 2010 RouterA BFD/7/EVENT:Send sess-down Msg, [Src:1.1.1.9,Dst:2.2.2.9,Loop1,Ctrl], instance:0, protocol:static # Display the static route information again. Router A communicates with Router B over the static route passing Router C now. <RouterA> display ip routing-table protocol static Public Routing Table : Static Summary Count : 2 Static Routing table Status : <Active> Summary Count : 1 Destination/Mask Proto Pre Cost NextHop Interface 120.1.1.0/24 Static 65 0 10.1.1.100 GE2/1/2 Static Routing table Status : <Inactive> Summary Count : 1 Destination/Mask Proto Pre Cost NextHop Interface 120.1.1.0/24 Static 60 0 2.2.2.9 16
Static route FRR configuration example Network requirements As shown in Figure 5, configure static routes on Router S, Router A, and Router D, and configure static route FRR so that when Link A fails, traffic can be switched to Link B immediately. Figure 5 Network diagram Router A Loop 0 1.1.1.1/32 Router S GE2/1/1 12.12.12.1/24 GE2/1/2 13.13.13.1/24 GE2/1/1 12.12.12.2/24 Link B Link A GE2/1/2 24.24.24.2/24 GE2/1/1 24.24.24.4/24 GE2/1/2 13.13.13.2/24 Router D Loop 0 4.4.4.4/32 Configuration procedure 1. Configure IP addresses for the interfaces on each router. (Details not shown.) 2. Configure static routes: Configure static routes on Router S, Router A, and Router D so that Router S can reach Loopback 0 on Router D and Router D can reach Loopback 0 on Router S. # Configure a static route on Router S. <RouterS> system-view [RouterS] ip route-static 4.4.4.4 32 GigabitEthernet 2/1/2 13.13.13.2 # Configure a static route on Router D. <RouterD> system-view [RouterD] ip route-static 1.1.1.1 32 GigabitEthernet 2/1/2 13.13.13.1 # Configure a static route on Router A. <RouterA> system-view [RouterA] ip route-static 4.4.4.4 32 GigabitEthernet 2/1/2 24.24.24.4 [RouterA] ip route-static 1.1.1.1 32 GigabitEthernet 2/1/1 12.12.12.1 3. Configure static route FRR: # Configure Router S. [RouterS] bfd echo-source-ip 1.1.1.1 [RouterS] ip ip-prefix abc index 10 permit 4.4.4.4 32 [RouterS] route-policy frr permit node 10 [RouterS-route-policy] if-match ip-prefix abc [RouterS-route-policy] apply fast-reroute backup-interface GigabitEthernet 2/1/1 backup-nexthop 12.12.12.2 [RouterS-route-policy] quit [RouterS] ip route-static fast-reroute route-policy frr # Configure Router D. [RouterD] bfd echo-source-ip 4.4.4.4 [RouterD] ip ip-prefix abc index 10 permit 1.1.1.1 32 [RouterD] route-policy frr permit node 10 [RouterD-route-policy] if-match ip-prefix abc [RouterD-route-policy] apply fast-reroute backup-interface GigabitEthernet 2/1/1 backup-nexthop 24.24.24.2 17