HPE FlexNetwork 5510 HI Switch Series

Transcription

1 HPE FlexNetwork 5510 HI Switch Series Layer 3 IP Routing Configuration Guide Part number: a Software version: Release 11xx Document version: 6W

2 Copyright 2015, 2016 Hewlett Packard Enterprise Development LP The information contained herein is subject to change without notice. The only warranties for Hewlett Packard Enterprise products and services are set forth in the express warranty statements accompanying such products and services. Nothing herein should be construed as constituting an additional warranty. Hewlett Packard Enterprise shall not be liable for technical or editorial errors or omissions contained herein. Confidential computer software. Valid license from Hewlett Packard Enterprise required for possession, use, or copying. Consistent with FAR and , Commercial Computer Software, Computer Software Documentation, and Technical Data for Commercial Items are licensed to the U.S. Government under vendor s standard commercial license. Links to third-party websites take you outside the Hewlett Packard Enterprise website. Hewlett Packard Enterprise has no control over and is not responsible for information outside the Hewlett Packard Enterprise website. Acknowledgments Intel, Itanium, Pentium, Intel Inside, and the Intel Inside logo are trademarks of Intel Corporation in the United States and other countries. Microsoft and Windows are either registered trademarks or trademarks of Microsoft Corporation in the United States and/or other countries. Adobe and Acrobat are trademarks of Adobe Systems Incorporated. Java and Oracle are registered trademarks of Oracle and/or its affiliates. UNIX is a registered trademark of The Open Group.

3 Contents Configuring basic IP routing 1 Routing table 1 Dynamic routing protocols 2 Route preference 2 Load sharing 3 Route backup 3 Route recursion 3 Route redistribution 3 Extension attribute redistribution 3 Configuring the maximum lifetime for routes and labels in the RIB 4 Configuring the maximum lifetime for routes in the FIB 4 Configuring the maximum number of ECMP routes 5 Enabling the enhanced ECMP mode 5 Enabling support for IPv6 routes with prefixes longer than 64 bits 6 Displaying and maintaining a routing table 6 Configuring static routing 8 Configuring a static route 8 Configuring BFD for static routes 9 Bidirectional control mode 9 Single-hop echo mode 10 Configuring static route FRR 11 Configuration guidelines 11 Configuration procedure 11 Displaying and maintaining static routes 12 Static route configuration examples 13 Basic static route configuration example 13 BFD for static routes configuration example (direct next hop) 15 BFD for static routes configuration example (indirect next hop) 17 Static route FRR configuration example 20 Configuring a default route 23 Configuring RIP 24 Overview 24 RIP route entries 24 Routing loop prevention 24 RIP operation 24 RIP versions 25 Protocols and standards 25 RIP configuration task list 25 Configuring basic RIP 26 Enabling RIP 26 Controlling RIP reception and advertisement on interfaces 27 Configuring a RIP version 27 Configuring RIP route control 28 Configuring an additional routing metric 28 Configuring RIPv2 route summarization 29 Disabling host route reception 29 Advertising a default route 30 Configuring received/redistributed route filtering 30 Configuring a preference for RIP 31 Configuring RIP route redistribution 31 Tuning and optimizing RIP networks 32 Configuration prerequisites 32 Configuring RIP timers 32 Enabling split horizon and poison reverse 32 i

4 Configuring the maximum number of ECMP routes 33 Enabling zero field check on incoming RIPv1 messages 34 Enabling source IP address check on incoming RIP updates 34 Configuring RIPv2 message authentication 34 Specifying a RIP neighbor 35 Configuring RIP network management 35 Configuring the RIP packet sending rate 35 Setting the maximum length of RIP packets 36 Configuring RIP GR 36 Configuring BFD for RIP 37 Configuring single-hop echo detection (for a directly connected RIP neighbor) 37 Configuring single-hop echo detection (for a specific destination) 37 Configuring bidirectional control detection 38 Configuring RIP FRR 38 Configuration restrictions and guidelines 39 Configuration prerequisites 39 Configuration procedure 39 Displaying and maintaining RIP 39 RIP configuration examples 40 Basic RIP configuration example 40 RIP route redistribution configuration example 43 RIP interface additional metric configuration example 45 RIP summary route advertisement configuration example 46 BFD for RIP configuration example (single-hop echo detection for a directly connected neighbor) 49 BFD for RIP configuration example (single hop echo detection for a specific destination) 51 BFD for RIP configuration example (bidirectional detection in BFD control packet mode) 54 RIP FRR configuration example 57 Configuring OSPF 60 Overview 60 OSPF packets 60 LSA types 60 OSPF areas 61 Router types 63 Route types 64 Route calculation 64 OSPF network types 65 DR and BDR 65 Protocols and standards 66 OSPF configuration task list 66 Enabling OSPF 68 Configuration prerequisites 68 Configuration guidelines 68 Enabling OSPF on a network 68 Enabling OSPF on an interface 69 Configuring OSPF areas 69 Configuring a stub area 70 Configuring an NSSA area 70 Configuring a virtual link 71 Configuring OSPF network types 71 Configuration prerequisites 72 Configuring the broadcast network type for an interface 72 Configuring the NBMA network type for an interface 72 Configuring the P2MP network type for an interface 73 Configuring the P2P network type for an interface 73 Configuring OSPF route control 74 Configuration prerequisites 74 Configuring OSPF route summarization 74 Configuring received OSPF route filtering 75 Configuring Type-3 LSA filtering 76 Configuring an OSPF cost for an interface 76 Configuring the maximum number of ECMP routes 77 ii

5 Configuring OSPF preference 77 Configuring OSPF route redistribution 78 Advertising a host route 79 Tuning and optimizing OSPF networks 79 Configuration prerequisites 79 Configuring OSPF timers 79 Specifying LSA transmission delay 80 Specifying SPF calculation interval 81 Specifying the LSA arrival interval 81 Specifying the LSA generation interval 81 Disabling interfaces from receiving and sending OSPF packets 82 Configuring stub routers 82 Configuring OSPF authentication 83 Adding the interface MTU into DD packets 84 Configuring a DSCP value for OSPF packets 84 Configuring the maximum number of external LSAs in LSDB 84 Configuring OSPF exit overflow interval 85 Enabling compatibility with RFC Logging neighbor state changes 85 Configuring OSPF network management 86 Configuring the LSU transmit rate 87 Enabling OSPF ISPF 87 Configuring prefix suppression 87 Configuring prefix prioritization 88 Configuring OSPF PIC 88 Configuring the number of OSPF logs 89 Configuring OSPF GR 89 Configuring OSPF GR restarter 90 Configuring OSPF GR helper 91 Triggering OSPF GR 91 Configuring OSPF NSR 92 Configuring BFD for OSPF 92 Configuring bidirectional control detection 92 Configuring single-hop echo detection 93 Configuring OSPF FRR 93 Configuration prerequisites 93 Configuration guidelines 93 Configuration procedure 94 Displaying and maintaining OSPF 95 OSPF configuration examples 96 Basic OSPF configuration example 96 OSPF route redistribution configuration example 99 OSPF route summarization configuration example 100 OSPF stub area configuration example 103 OSPF NSSA area configuration example) 106 OSPF DR election configuration example 108 OSPF virtual link configuration example 112 OSPF GR configuration example 114 OSPF NSR configuration example 116 BFD for OSPF configuration example 118 OSPF FRR configuration example 121 Troubleshooting OSPF configuration 123 No OSPF neighbor relationship established 123 Incorrect routing information 124 Configuring IS-IS 125 Overview 125 Terminology 125 IS-IS address format 125 NET 126 IS-IS area 127 IS-IS network types 128 iii

6 IS-IS PDUs 129 Protocols and standards 131 IS-IS configuration task list 131 Configuring basic IS-IS 132 Configuration prerequisites 132 Enabling IS-IS 132 Configuring the IS level and circuit level 133 Configuring P2P network type for an interface 133 Configuring IS-IS route control 134 Configuration prerequisites 134 Configuring IS-IS link cost 134 Specifying a preference for IS-IS 135 Configuring the maximum number of ECMP routes 136 Configuring IS-IS route summarization 136 Advertising a default route 136 Configuring IS-IS route redistribution 137 Configuring IS-IS route filtering 137 Configuring IS-IS route leaking 138 Tuning and optimizing IS-IS networks 139 Configuration prerequisites 139 Specifying the interval for sending IS-IS hello packets 139 Specifying the IS-IS hello multiplier 139 Specifying the interval for sending IS-IS CSNP packets 140 Configuring a DIS priority for an interface 140 Enabling source address check for hello packets on a PPP interface 140 Disabling an interface from sending/receiving IS-IS packets 141 Enabling an interface to send small hello packets 141 Configuring LSP parameters 141 Controlling SPF calculation interval 144 Configuring convergence priorities for specific routes 144 Setting the LSDB overload bit 144 Configuring system ID to host name mappings 145 Enabling the logging of neighbor state changes 146 Enabling IS-IS ISPF 146 Configuring IS-IS network management 146 Enhancing IS-IS network security 147 Configuration prerequisites 147 Configuring neighbor relationship authentication 147 Configuring area authentication 148 Configuring routing domain authentication 148 Configuring IS-IS GR 149 Configuring IS-IS NSR 150 Configuring BFD for IS-IS 150 Configuring IS-IS FRR 151 Configuration prerequisites 151 Configuration guidelines 151 Configuring IS-IS FRR to automatically calculate a backup next hop 151 Configuring IS-IS FRR using a routing policy 152 Configuring BFD for IS-IS FRR 152 Displaying and maintaining IS-IS 152 IS-IS configuration examples 153 Basic IS-IS configuration example 153 DIS election configuration example 158 IS-IS route redistribution configuration example 162 IS-IS authentication configuration example 165 IS-IS GR configuration example 168 IS-IS NSR configuration example 169 BFD for IS-IS configuration example 172 IS-IS FRR configuration example 175 Configuring BGP 178 Overview 178 iv

7 BGP speaker and BGP peer 178 BGP message types 178 BGP path attributes 178 BGP route selection 182 BGP route advertisement rules 182 BGP load balancing 182 Settlements for problems in large-scale BGP networks 184 MP-BGP 186 BGP configuration views 187 Protocols and standards 188 BGP configuration task list 189 Configuring basic BGP 191 Enabling BGP 192 Configuring a BGP peer 192 Configuring dynamic BGP peers 194 Configuring a BGP peer group 195 Specifying the source address of TCP connections 202 Generating BGP routes 203 Injecting a local network 203 Redistributing IGP routes 204 Controlling route distribution and reception 205 Configuring BGP route summarization 205 Advertising optimal routes in the IP routing table 207 Advertising a default route to a peer or peer group 207 Limiting routes received from a peer or peer group 208 Configuring BGP route filtering policies 209 Configuring BGP update sending delay 213 Configuring BGP route dampening 214 Controlling BGP path selection 214 Specifying a preferred value for routes received 214 Configuring preferences for BGP routes 215 Configuring the default local preference 216 Configuring the MED attribute 217 Configuring the NEXT_HOP attribute 221 Configuring the AS_PATH attribute 223 Tuning and optimizing BGP networks 228 Configuring the keepalive interval and hold time 228 Configuring the interval for sending updates for the same route 229 Enabling BGP to establish an EBGP session over multiple hops 230 Enabling immediate re-establishment of direct EBGP connections upon link failure 231 Enabling 4-byte AS number suppression 231 Enabling MD5 authentication for BGP peers 232 Configuring BGP load balancing 233 Configuring IPsec for IPv6 BGP 234 Disabling BGP to establish a session to a peer or peer group 234 Configuring GTSM for BGP 235 Configuring BGP soft-reset 236 Protecting an EBGP peer when memory usage reaches level 2 threshold 240 Configuring a large-scale BGP network 241 Configuring BGP community 241 Configuring BGP route reflection 242 Configuring a BGP confederation 244 Configuring BGP GR 245 Configuring BGP NSR 246 Enabling SNMP notifications for BGP 246 Enabling logging of session state changes 247 Enabling logging for BGP route flapping 247 Configuring BFD for BGP 248 Configuring BGP FRR 249 Configuring 6PE 252 Configuring basic 6PE 252 Configuring optional 6PE capabilities 253 v

8 Displaying and maintaining BGP 254 IPv4 BGP configuration examples 257 Basic BGP configuration example 257 BGP and IGP route redistribution configuration example 261 BGP route summarization configuration example 264 BGP load balancing configuration example 267 BGP community configuration example 270 BGP route reflector configuration example 273 BGP confederation configuration example 275 BGP path selection configuration example 279 BGP GR configuration example 282 BFD for BGP configuration example 283 BGP FRR configuration example 287 IPv6 BGP configuration examples 290 IPv6 BGP basic configuration example 290 IPv6 BGP route reflector configuration example 293 6PE configuration example 296 BFD for IPv6 BGP configuration example 299 IPv6 BGP FRR configuration example 302 IPsec for IPv6 BGP packets configuration example 306 Troubleshooting BGP 310 Symptom 310 Analysis 310 Solution 310 Configuring PBR 312 Overview 312 Policy 312 PBR and Track 313 PBR configuration task list 313 Configuring a policy 313 Creating a node 313 Configuring match criteria for a node 314 Configuring actions for a node 314 Configuring PBR 314 Configuring local PBR 314 Configuring interface PBR 315 Displaying and maintaining PBR 315 PBR configuration examples 315 Packet type-based local PBR configuration example 315 Packet type-based interface PBR configuration example 317 Configuring IPv6 static routing 320 Configuring an IPv6 static route 320 Configuring BFD for IPv6 static routes 320 Bidirectional control mode 321 Single-hop echo mode 321 Displaying and maintaining IPv6 static routes 322 IPv6 static routing configuration examples 322 Basic IPv6 static route configuration example 322 BFD for IPv6 static routes configuration example (direct next hop) 324 BFD for IPv6 static routes configuration example (indirect next hop) 327 Configuring an IPv6 default route 330 Configuring RIPng 331 Overview 331 RIPng route entries 331 RIPng packets 331 Protocols and standards 332 RIPng configuration task list 332 Configuring basic RIPng 332 vi

9 Configuring RIPng route control 333 Configuring an additional routing metric 333 Configuring RIPng route summarization 333 Advertising a default route 334 Configuring received/redistributed route filtering 334 Configuring a preference for RIPng 334 Configuring RIPng route redistribution 335 Tuning and optimizing the RIPng network 335 Configuring RIPng timers 335 Configuring split horizon and poison reverse 335 Configuring zero field check on RIPng packets 336 Configuring the maximum number of ECMP routes 336 Configuring RIPng GR 337 Applying an IPsec profile 337 Displaying and maintaining RIPng 338 RIPng configuration examples 339 Basic RIPng configuration example 339 RIPng route redistribution configuration example 341 RIPng IPsec profile configuration example 344 Configuring OSPFv3 347 Overview 347 OSPFv3 packets 347 OSPFv3 LSA types 347 Protocols and standards 348 OSPFv3 configuration task list 348 Enabling OSPFv3 349 Configuring OSPFv3 area parameters 350 Configuration prerequisites 350 Configuring a stub area 350 Configuring an NSSA area 350 Configuring an OSPFv3 virtual link 351 Configuring OSPFv3 network types 351 Configuration prerequisites 352 Configuring the OSPFv3 network type for an interface 352 Configuring an NBMA or P2MP neighbor 352 Configuring OSPFv3 route control 353 Configuration prerequisites 353 Configuring OSPFv3 route summarization 353 Configuring OSPFv3 received route filtering 354 Configuring Inter-Area-Prefix LSA filtering 354 Configuring an OSPFv3 cost for an interface 354 Configuring the maximum number of OSPFv3 ECMP routes 355 Configuring a preference for OSPFv3 355 Configuring OSPFv3 route redistribution 356 Tuning and optimizing OSPFv3 networks 357 Configuration prerequisites 357 Configuring OSPFv3 timers 357 Specifying LSA transmission delay 358 Specifying SPF calculation interval 358 Specifying the LSA generation interval 359 Configuring a DR priority for an interface 359 Ignoring MTU check for DD packets 359 Disabling interfaces from receiving and sending OSPFv3 packets 360 Enabling the logging of neighbor state changes 360 Configuring OSPFv3 network management 360 Configuring the LSU transmit rate 361 Configuring stub routers 362 Configuring prefix suppression 362 Configuring OSPFv3 GR 363 Configuring GR restarter 363 Configuring GR helper 364 vii

10 Triggering OSPFv3 GR 364 Configuring OSPFv3 NSR 364 Configuring BFD for OSPFv3 365 Applying an IPsec profile 365 Displaying and maintaining OSPFv3 367 OSPFv3 configuration examples 368 OSPFv3 stub area configuration example 368 OSPFv3 NSSA area configuration example 372 OSPFv3 DR election configuration example 374 OSPFv3 route redistribution configuration example 377 OSPFv3 route summarization configuration example 380 OSPFv3 GR configuration example 384 OSPFv3 NSR configuration example 385 BFD for OSPFv3 configuration example 386 OSPFv3 IPsec profile configuration example 389 Configuring IPv6 IS-IS 394 Overview 394 Configuring basic IPv6 IS-IS 394 Configuring IPv6 IS-IS route control 394 Tuning and optimizing IPv6 IS-IS networks 396 Configuration prerequisites 396 Assigning a convergence priority to IPv6 IS-IS routes 396 Configuring BFD for IPv6 IS-IS 396 Displaying and maintaining IPv6 IS-IS 397 IPv6 IS-IS configuration examples 397 IPv6 IS-IS basic configuration example 397 BFD for IPv6 IS-IS configuration example 401 Configuring IPv6 PBR 405 Overview 405 Policy 405 PBR and Track 406 IPv6 PBR configuration task list 406 Configuring an IPv6 policy 406 Creating an IPv6 node 406 Configuring match criteria for an IPv6 node 407 Configuring actions for an IPv6 node 407 Configuring IPv6 PBR 407 Configuring IPv6 local PBR 407 Configuring IPv6 interface PBR 408 Displaying and maintaining IPv6 PBR 408 IPv6 PBR configuration examples 409 Packet type-based IPv6 local PBR configuration example 409 Packet type-based IPv6 interface PBR configuration example 410 Configuring routing policies 413 Overview 413 Filters 413 Routing policy 413 Configuring filters 414 Configuration prerequisites 414 Configuring an IP prefix list 414 Configuring an AS path list 415 Configuring a community list 415 Configuring an extended community list 416 Configuring a routing policy 416 Configuration prerequisites 416 Creating a routing policy 416 Configuring if-match clauses 416 Configuring apply clauses 418 Configuring the continue clause 419 viii

11 Displaying and maintaining the routing policy 420 Routing policy configuration examples 420 Routing policy configuration example for IPv4 route redistribution 420 Routing policy configuration example for IPv6 route redistribution 423 Document conventions and icons 425 Conventions 425 Network topology icons 426 Support and other resources 427 Accessing Hewlett Packard Enterprise Support 427 Accessing updates 427 Websites 428 Customer self repair 428 Remote support 428 Documentation feedback 428 ix

12 Configuring basic IP routing The term "interface" in this chapter collectively refers to Layer 3 interfaces, including VLAN interfaces and Layer 3 Ethernet interfaces. You can set an Ethernet port as a Layer 3 interface by using the port link-mode route command (see Layer 2 LAN Switching Configuration Guide). IP routing directs IP packet forwarding on routers based on a routing table. This chapter focuses on unicast routing protocols. For more information about multicast routing protocols, see IP Multicast Configuration Guide. Routing table A RIB contains the global routing information and related information, including route recursion, route redistribution, and route extension information. The router selects optimal routes from the routing table and puts them into the FIB table. It uses the FIB table to forward packets. For more information about the FIB table, see Layer 3 IP Services Configuration Guide. Table 1 categorizes routes by different criteria. Table 1 Route categories Criterion Destination Whether the destination is directly connected Origin Categories Network route The destination is a network. The subnet mask is less than 32 bits. Host route The destination is a host. The subnet mask is 32 bits. Direct route The destination is directly connected. Indirect route The 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. To view brief information about a routing table, use the display ip routing-table command. <Sysname> display ip routing-table Destinations : 19 Routes : 19 Destination/Mask Proto Pre Cost NextHop Interface /32 Direct InLoop /24 Direct Vlan /32 Direct Vlan /32 Direct InLoop /32 Direct Vlan /24 Static Vlan /24 OSPF Vlan3... 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

13 Pre Preference of the route. Among routes to the same destination, the route with the highest preference is optimal. Cost If multiple routes to a destination have the same preference, the one with the smallest cost is the optimal route. NextHop Next hop. Interface Output interface. Dynamic routing protocols Static routes work well in small, stable networks. They are easy to configure and require fewer system resources. However, in networks where topology changes occur frequently, a typical practice is to configure a dynamic routing protocol. Compared with static routing, a dynamic routing protocol is complicated to configure, requires more router resources, and consumes more network resources. Dynamic routing protocols dynamically collect and report reachability information to adapt to topology changes. They are suitable for large networks. Dynamic routing protocols can be classified by different criteria, as shown in Table 2. Table 2 Categories of dynamic routing protocols Criterion Operation scope Routing algorithm Destination address type IP version Categories IGPs Work within an AS. Examples include RIP, OSPF, and IS-IS. EGPs Work between ASs. The most popular EGP is BGP. Distance-vector protocols Examples include RIP and BGP. BGP is also considered a path-vector protocol. Link-state protocols Examples include OSPF and IS-IS. Unicast routing protocols Examples include RIP, OSPF, BGP, and IS-IS. Multicast routing protocols Examples include PIM-SM and PIM-DM. IPv4 routing protocols Examples include RIP, OSPF, BGP, and IS-IS. IPv6 routing protocols Examples include RIPng, OSPFv3, IPv6 BGP, and IPv6 IS-IS. 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. The following table lists the route types and default preferences. The smaller the value, the higher the preference. Table 3 Route types and default route preferences Route type Preference Direct route 0 Multicast static route 1 OSPF 10 IS-IS 15 2

14 Route type Preference Unicast 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, IS-IS, and 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 primary route and others are secondary routes. The router forwards matching packets through the primary route. When the primary route fails, the route with the highest preference among the secondary routes is selected to forward packets. When the primary route recovers, the router uses it to forward packets. Route recursion To use a route that has an indirectly connected next hop, a router must perform route recursion to find the output interface to reach the next hop. The RIB records and saves route recursion information, including brief information about related routes, recursive paths, and recursion depth. Route redistribution Route redistribution enables routing protocols to learn routing 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. The RIB records redistribution relationships of routing protocols. Extension attribute redistribution Extension attribute redistribution enables routing protocols to learn route extension attributes from each other, including BGP extended community attributes, OSPF area IDs, route types, and router IDs. 3

15 The RIB records extended attributes of each routing protocol and redistribution relationships of different routing protocol extended attributes. Configuring the maximum lifetime for routes and labels in the RIB Perform this task to prevent routes of a certain protocol from being aged out due to slow protocol convergence resulting from a large number of route entries or long GR period. The configuration takes effect at the next protocol or RIB process switchover. To configure the maximum lifetime for routes and labels in the RIB (IPv4): 1. Enter system view. system-view 2. Enter RIB view. rib 3. Create a RIB IPv4 address family and enter RIB IPv4 address family view. 4. Configure the maximum lifetime for IPv4 routes and labels in the RIB. address-family ipv4 protocol protocol lifetime seconds By default, no RIB IPv4 address family is created. By default, the maximum lifetime for routes and labels in the RIB is 480 seconds. To configure the maximum route lifetime for routes and labels in the RIB (IPv6): 1. Enter system view. system-view 2. Enter RIB view. rib 3. Create a RIB IPv6 address family and enter RIB IPv6 address family view. 4. Configure the maximum lifetime for IPv6 routes and labels in the RIB. address-family ipv6 protocol protocol lifetime seconds By default, no RIB IPv6 address family is created. By default, the maximum lifetime for routes and labels in the RIB is 480 seconds. Configuring the maximum lifetime for routes in the FIB When GR or NSR is disabled, FIB entries must be retained for some time after a protocol process switchover or RIB process switchover. When GR or NSR is enabled, FIB entries must be removed immediately after a protocol or RIB process switchover to avoid routing issues. Perform this task to meet such requirements. To configure the maximum lifetime for routes in the FIB (IPv4): 1. Enter system view. system-view 2. Enter RIB view. rib 4

16 3. Create a RIB IPv4 address family and enter its view. 4. Configure the maximum lifetime for IPv4 routes in the FIB. address-family ipv4 fib lifetime seconds To configure the maximum lifetime for routes in the FIB (IPv6): 1. Enter system view. system-view 2. Enter RIB view. rib By default, no RIB IPv4 address family is created. By default, the maximum lifetime for routes in the FIB is 600 seconds. 3. Create a RIB IPv6 address family and enter its view. 4. Configure the maximum lifetime for IPv6 routes in the FIB. address-family ipv6 fib lifetime seconds By default, no RIB IPv6 address family is created. By default, the maximum lifetime for routes in the FIB is 600 seconds. Configuring the maximum number of ECMP routes This configuration takes effect at reboot. Make sure the reboot does not impact your network. To set the maximum number of ECMP routes: 1. Enter system view. system-view 2. Set the maximum number of ECMP routes. max-ecmp-num number By default, the maximum number of ECMP routes is 8. Enabling the enhanced ECMP mode When one or multiple ECMP routes fail, the default ECMP mode enables the device to reallocate all traffic to the remaining routes. The enhanced ECMP mode enables the device to reallocate only the traffic of the failed routes to the remaining routes, which ensures forwarding continuity. This configuration takes effect at reboot. Make sure the reboot does not impact your network. To enable the enhanced ECMP mode: 1. Enter system view. system-view 2. Enable the enhanced ECMP mode. ecmp mode enhanced By default, the enhanced ECMP mode is disabled. 5

17 Enabling support for IPv6 routes with prefixes longer than 64 bits This feature enables a device to support IPv6 routes with prefixes longer than 64 bits. Before configuration, the RIB supports a maximum of IPv4 routes or IPv6 routes with prefixes no longer than 64 bits. After configuration, the RIB supports a maximum of IPv4 routes or 8192 IPv6 routes with prefixes no longer than 64 bits. The remaining RIB space stores a maximum of 4096 IPv6 routes with prefixes longer than 64 bits. This configuration takes effect at next reboot. Make sure the reboot does not impact your network. To enable support for IPv6 routes with prefixes longer than 64 bits: 1. Enter system view. system-view 2. Enable support for IPv6 routes with prefixes longer than 64 bits. switch-routing-mode ipv6-128 By default, the device does not support IPv6 routes with prefixes longer than 64 bits. Displaying and maintaining a routing table Execute display commands in any view and reset commands in user view. Task Display the ECMP mode. Display routing table information. Display information about routes permitted by an IPv4 basic ACL. Display information about routes to a specific destination address. Display information about routes to a range of destination addresses. Display information about routes permitted by an IP prefix list. Display information about routes installed by a protocol. Display IPv4 route statistics. Display the maximum number of ECMP routes. Display route attribute information in the RIB. Display RIB GR state information. Command display ecmp mode display ip routing-table [ vpn-instance vpn-instance-name ] [ verbose ] [ standby slot slot-number ] display ip routing-table [ vpn-instance vpn-instance-name ] acl acl-number [ verbose ] [ standby slot slot-number ] display ip routing-table [ vpn-instance vpn-instance-name ] ip-address [ mask mask-length ] [ longer-match ] [ verbose ] [ standby slot slot-number ] display ip routing-table [ vpn-instance vpn-instance-name ] ip-address1 to ip-address2 [ verbose ] [ standby slot slot-number ] display ip routing-table [ vpn-instance vpn-instance-name ] prefix-list prefix-list-name [ verbose ] [ standby slot slot-number ] display ip routing-table [ vpn-instance vpn-instance-name ] protocol protocol [ inactive verbose ] [ standby slot slot-number ] display ip routing-table [ vpn-instance vpn-instance-name ] statistics [ standby slot slot-number ] display max-ecmp-num display rib attribute [ attribute-id ] [ standby slot slot-number ] display rib graceful-restart 6

18 Task Display next hop information in the RIB. Display next hop information for direct routes. Clear IPv4 route statistics. Display IPv6 routing table information. Display information about routes to an IPv6 destination address. Display information about routes permitted by an IPv6 basic ACL. Display information about routes to a range of IPv6 destination addresses. Display information about routes permitted by an IPv6 prefix list. Display information about routes installed by an IPv6 protocol. Display IPv6 route statistics. Display route attribute information in the IPv6 RIB. Display IPv6 RIB GR state information. Display next hop information in the IPv6 RIB. Display next hop information for IPv6 direct routes. Clear IPv6 route statistics. Command display rib nib [ self-originated ] [ nib-id ] [ verbose ] [ standby slot slot-number ] display rib nib protocol protocol-name [ verbose ] [ standby slot slot-number ] display route-direct nib [ nib-id ] [ verbose ] reset ip routing-table statistics protocol [ vpn-instance vpn-instance-name ] { protocol all } [ standby slot slot-number ] display ipv6 routing-table [ vpn-instance vpn-instance-name ] [ verbose ] [ standby slot slot-number ] display ipv6 routing-table [ vpn-instance vpn-instance-name ] ipv6-address [ prefix-length ] [ longer-match ] [ verbose ] [ standby slot slot-number ] display ipv6 routing-table [ vpn-instance vpn-instance-name ] acl acl6-number [ verbose ] [ standby slot slot-number ] display ipv6 routing-table [ vpn-instance vpn-instance-name ] ipv6-address1 to ipv6-address2 [ verbose ] [ standby slot slot-number ] display ipv6 routing-table [ vpn-instance vpn-instance-name ] prefix-list prefix-list-name [ verbose ] [ standby slot slot-number ] display ipv6 routing-table [ vpn-instance vpn-instance-name ] protocol protocol [ inactive verbose ] [ standby slot slot-number ] display ipv6 routing-table [ vpn-instance vpn-instance-name ] statistics [ standby slot slot-number ] display ipv6 rib attribute [ attribute-id ] [ standby slot slot-number ] display ipv6 rib graceful-restart display ipv6 rib nib [ self-originated ] [ nib-id ] [ verbose ] [ standby slot slot-number ] display ipv6 rib nib protocol protocol-name [ verbose ] [ standby slot slot-number ] display ipv6 route-direct nib [ nib-id ] [ verbose ] reset ipv6 routing-table statistics protocol [ vpn-instance vpn-instance-name ] { protocol all } [ standby slot slot-number ] 7

19 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 the physical parameters for related interfaces. Configure the link-layer attributes for related interfaces. Configure the IP addresses for related interfaces. You can associate Track with a static route to monitor the reachability of the next hops. For more information about Track, see High Availability Configuration Guide. To configure a static route: 1. Enter system view. system-view 2. Configure a static route. 3. (Optional.) Configure the default preference for static routes. 4. (Optional.) Delete all static routes, including the default route. Method 1: ip route-static dest-address { mask-length mask } { interface-type interface-number [ next-hop-address ] next-hop-address [ track track-entry-number ] vpn-instance d-vpn-instance-name next-hop-address [ track track-entry-number ] } [ permanent ] [ preference preference-value ] [ tag tag-value ] [ description description-text ] Method 2: ip route-static vpn-instance s-vpn-instance-name dest-address { mask-length mask } { interface-type interface-number [ next-hop-address ] next-hop-address [ public ] [ track track-entry-number ] vpn-instance d-vpn-instance-name next-hop-address [ track track-entry-number ] } [ permanent ] [ preference preference-value ] [ tag tag-value ] [ description description-text ] ip route-static default-preference default-preference-value delete [ vpn-instance vpn-instance-name ] static-routes all By default, no static route is configured. The default setting is 60. To delete one static route, use the undo ip route-static command. 8

20 Configuring BFD for static routes IMPORTANT: Enabling BFD for a flapping route could worsen the situation. 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. Bidirectional control mode To use BFD bidirectional control detection between two devices, enable BFD control mode for each device's static route destined to the peer. To configure a static route and enable BFD control mode, use one of the following methods: Specify an output interface and a direct next hop. Specify an indirect next hop and a specific BFD packet source address for the static route. To configure BFD control mode for a static route (direct next hop): 1. Enter system view. system-view 2. Configure BFD control mode for a static route. Method 1: ip route-static dest-address { mask-length mask } 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 dest-address { mask-length mask } interface-type interface-number next-hop-address bfd control-packet [ preference preference-value ] [ tag tag-value ] [ description description-text ] To configure BFD control mode for a static route (indirect next hop): By default, BFD control mode for a static route is not configured. 1. Enter system view. system-view 9

21 2. Configure BFD control mode for a static route. Method 1: ip route-static dest-address { mask-length mask } { next-hop-address bfd control-packet bfd-source ip-address vpn-instance d-vpn-instance-name 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 dest-address { mask-length mask } { next-hop-address bfd control-packet bfd-source ip-address vpn-instance d-vpn-instance-name next-hop-address bfd control-packet bfd-source ip-address } [ preference preference-value ] [ tag tag-value ] [ description description-text ] By default, BFD control mode for a static route is not configured. Single-hop echo mode With BFD echo mode enabled for a static route, the output interface sends BFD echo packets to the destination device, which loops the packets back to test the link reachability. IMPORTANT: Do not use BFD for a static route with the output interface in spoofing state. To configure BFD echo mode for a static route: 1. Enter system view. system-view 2. Configure the source address of echo packets. 3. Configure BFD echo mode for a static route. bfd echo-source-ip ip-address Method 1: ip route-static dest-address { mask-length mask } 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 dest-address { mask-length mask } interface-type interface-number next-hop-address bfd echo-packet [ preference preference-value ] [ tag tag-value ] [ description description-text ] By default, the source address of echo packets is not configured. For more information about this command, see High Availability Command Reference. By default, BFD echo mode for a static route is not configured. 10

22 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) uses BFD to detect failures and enables fast rerouting to minimize the impact of link or node failures. Figure 1 Network diagram As shown in Figure 1, upon a link failure, packets are directed to the backup next hop to avoid traffic interruption. You can either specify a backup next hop for FRR or enable FRR to automatically select a backup next hop (which must be configured in advance). Configuration guidelines Do not use static route FRR and BFD (for a static route) at the same time. Static route does not take effect when the backup output interface is unavailable. Equal-cost routes do not support static route FRR. The backup output interface and next hop cannot be modified, and cannot be the same as the primary output interface and next hop. Static route FRR is available only when the state of primary link (with Layer 3 interfaces staying up) changes from bidirectional to unidirectional or down. Configuration procedure Configuring static route FRR by specifying a backup next hop 1. Enter system view. system-view 2. Configure the source address of BFD echo packets. bfd echo-source-ip ip-address By default, the source address of BFD echo packets is not configured. For more information about this command, see High Availability Command Reference. 11

23 3. Configure static route FRR. Method 1: ip route-static dest-address { mask-length mask } interface-type interface-number [ next-hop-address [ backup-interface interface-type interface-number [ backup-nexthop backup-nexthop-address ] ] ] [ permanent ] Method 2: ip route-static vpn-instance s-vpn-instance-name dest-address { mask-length mask } interface-type interface-number [ next-hop-address [ backup-interface interface-type interface-number [ backup-nexthop backup-nexthop-address ] ] ] [ permanent ] Configuring static route FRR to automatically select a backup next hop 1. Enter system view. system-view By default, static route FRR is not configured. 2. Configure the source address of BFD echo packets. 3. Configure static route FRR to automatically select a backup next hop. bfd echo-source-ip ip-address ip route-static fast-reroute auto By default, the source address of BFD echo packets is not configured. For more information about this command, see High Availability Command Reference. By default, static route FRR is disabled. Enabling BFD echo packet mode for static route FRR By default, static route FRR does not use BFD to detect primary link failures. Perform this task to enable static route FRR to use BFD echo packet mode for fast failure detection on the primary link. To enable BFD echo packet mode for static route FRR: 1. Enter system view. system-view 2. Configure the source IP address of BFD echo packets. 3. Enable BFD echo packet mode for static route FRR. bfd echo-source-ip ip-address ip route-static primary-path-detect bfd echo By default, the source IP address of BFD echo packets is not configured. By default, BFD echo mode for static route FRR is disabled. Displaying and maintaining static routes Execute display commands in any view. Task Command Display static route information. display ip routing-table protocol static [ inactive verbose ] 12

24 Task Display static route next hop information. Display static routing table information. Command display route-static nib [ nib-id ] [ verbose ] display route-static routing-table [ vpn-instance vpn-instance-name ] [ ip-address { mask-length mask } ] Static route configuration examples Basic static route configuration example Network requirements As shown in Figure 2, configure static routes on the switches for interconnections between any two hosts. Figure 2 Network diagram Configuration procedure 1. Configure IP addresses for interfaces. (Details not shown.) 2. Configure static routes: # Configure a default route on Switch A. <SwitchA> system-view [SwitchA] ip route-static # Configure two static routes on Switch B. <SwitchB> system-view [SwitchB] ip route-static [SwitchB] ip route-static # Configure a default route on Switch C. <SwitchC> system-view [SwitchC] ip route-static Configure the default gateways of Host A, Host B, and Host C as , , and (Details not shown.) Verifying the configuration # Display static routes on Switch A. 13

25 [SwitchA] display ip routing-table protocol static Summary Count : 1 Static Routing table Status : <Active> Summary Count : 1 Destination/Mask Proto Pre Cost NextHop Interface /0 Static Vlan500 Static Routing table Status : <Inactive> Summary Count : 0 # Display static routes on Switch B. [SwitchB] display ip routing-table protocol static Summary Count : 2 Static Routing table Status : <Active> Summary Count : 2 Destination/Mask Proto Pre Cost NextHop Interface /24 Static Vlan500 Static Routing table Status : <Inactive> Summary Count : 0 # 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 Pinging with 32 bytes of data: Reply from : bytes=32 time=1ms TTL=126 Reply from : bytes=32 time=1ms TTL=126 Reply from : bytes=32 time=1ms TTL=126 Reply from : bytes=32 time=1ms TTL=126 Ping statistics for : 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 Tracing route to over a maximum of 30 hops 1 <1 ms <1 ms <1 ms <1 ms <1 ms <1 ms ms <1 ms <1 ms

26 Trace complete. BFD for static routes configuration example (direct next hop) Network requirements Configure the following, as shown in Figure 3: Configure a static route to subnet /24 on Switch A. Configure a static route to subnet /24 on Switch B. Enable BFD for both routes. Configure a static route to subnet /24 and a static route to subnet /24 on Switch C. When the link between Switch A and Switch B through the Layer 2 switch fails, BFD can detect the failure immediately. Switch A then communicates with Switch B through Switch C. Figure 3 Network diagram Table 4 Interface and IP address assignment Device Interface IP address Switch A VLAN-interface /24 Switch A VLAN-interface /24 Switch B VLAN-interface /24 Switch B VLAN-interface /24 Switch C VLAN-interface /24 Switch C VLAN-interface /24 Configuration procedure 1. Configure IP addresses for the interfaces. (Details not shown.) 2. Configure static routes and BFD: # Configure static routes on Switch A and enable BFD control mode for the static route that traverses the Layer 2 switch. <SwitchA> system-view [SwitchA] interface vlan-interface 10 [SwitchA-vlan-interface10] bfd min-transmit-interval 500 [SwitchA-vlan-interface10] bfd min-receive-interval 500 [SwitchA-vlan-interface10] bfd detect-multiplier 9 [SwitchA-vlan-interface10] quit 15

27 [SwitchA] ip route-static vlan-interface bfd control-packet [SwitchA] ip route-static vlan-interface preference 65 [SwitchA] quit # Configure static routes on Switch B and enable BFD control mode for the static route that traverses the Layer 2 switch. <SwitchB> system-view [SwitchB] interface vlan-interface 10 [SwitchB-vlan-interface10] bfd min-transmit-interval 500 [SwitchB-vlan-interface10] bfd min-receive-interval 500 [SwitchB-vlan-interface10] bfd detect-multiplier 9 [SwitchB-vlan-interface10] quit [SwitchB] ip route-static vlan-interface bfd control-packet [SwitchB] ip route-static vlan-interface preference 65 [SwitchB] quit # Configure static routes on Switch C. <SwitchC> system-view [SwitchC] ip route-static [SwitchC] ip route-static Verifying the configuration # Display BFD sessions on Switch A. <SwitchA> display bfd session Total Session Num: 1 Up Session Num: 1 Init Mode: Active IPv4 Session Working Under Ctrl Mode: LD/RD SourceAddr DestAddr State Holdtime Interface 4/ Up 2000ms Vlan10 The output shows that the BFD session has been created. # Display the static routes on Switch A. <SwitchA> display ip routing-table protocol static Summary Count : 1 Static Routing table Status : <Active> Summary Count : 1 Destination/Mask Proto Pre Cost NextHop Interface /24 Static Vlan10 Static Routing table Status : <Inactive> Summary Count : 0 The output shows that Switch A communicates with Switch B through VLAN-interface 10. Then the link over VLAN-interface 10 fails. # Display static routes on Switch A. <SwitchA> display ip routing-table protocol static 16

28 Summary Count : 1 Static Routing table Status : <Active> Summary Count : 1 Destination/Mask Proto Pre Cost NextHop Interface /24 Static Vlan11 Static Routing table Status : <Inactive> Summary Count : 0 The output shows that Switch A communicates with Switch B through VLAN-interface 11. BFD for static routes configuration example (indirect next hop) Network requirements Figure 4 shows the network topology as follows: Switch A has a route to interface Loopback 1 ( /32) on Switch B, with the output interface VLAN-interface 10. Switch B has a route to interface Loopback 1 ( /32) on Switch A, with the output interface VLAN-interface 12. Switch D has a route to /32, with the output interface VLAN-interface 10, and a route to /32, with the output interface VLAN-interface 12. Configure the following: Configure a static route to subnet /24 on Switch A. Configure a static route to subnet /24 on Switch B. Enable BFD for both routes. Configure a static route to subnet /24 and a static route to subnet /24 on both Switch C and Switch D. When the link between Switch A and Switch B through Switch D fails, BFD can detect the failure immediately. Switch A then communicates with Switch B through Switch C. Figure 4 Network diagram 17