Cisco ASR 9000 Series User manual

Cisco ASR 9000 Series Aggregation Services Router Routing
Configuration Guide, Release 5.1.x
First Published: 2013-09-01
Last Modified: 2014-04-01
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Text Part Number: OL-30423-03

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CONTENTS
Preface Preface xxvii
Obtaining Documentation and Submitting a Service Request xxvii
CHAPTER 1 New and Changed Routing Features 1
New and Changed Routing Features 1
CHAPTER 2 Implementing BGP 7
Prerequisites for Implementing BGP 9
Information About Implementing BGP 9
BGP Functional Overview 10
BGP Router Identifier 10
BGP Default Limits 11
BGP Next Hop Tracking 12
Scoped IPv4/VPNv4 Table Walk 13
Reordered Address Family Processing 13
New Thread for Next-Hop Processing 13
show, clear, and debug Commands 13
Autonomous System Number Formats in BGP 14
2-byte Autonomous System Number Format 14
4-byte Autonomous System Number Format 14
as-format Command 14
BGP Configuration 14
Configuration Modes 15
Router Configuration Mode 15
Router Address Family Configuration Mode 15
Neighbor Configuration Mode 15
Neighbor Address Family Configuration Mode 15
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VRF Configuration Mode 15
VRF Address Family Configuration Mode 16
Configuring Resilient Per-CE Label Allocation Mode Under VRF Address
Family 16
Configuring Resilient Per-CE Label Allocation Mode Using a
Route-Policy 18
VRF Neighbor Configuration Mode 19
VRF Neighbor Address Family Configuration Mode 19
VPNv4 Address Family Configuration Mode 19
L2VPN Address Family Configuration Mode 20
Neighbor Submode 20
Configuration Templates 21
Template Inheritance Rules 22
Viewing Inherited Configurations 25
show bgp neighbors 26
show bgp af-group 27
show bgp session-group 28
show bgp neighbor-group 29
No Default Address Family 30
Neighbor Address Family Combinations 30
Routing Policy Enforcement 31
Table Policy 32
Update Groups 33
BGP Update Generation and Update Groups 33
BGP Update Group 33
BGP Cost Community 33
How BGP Cost Community Influences the Best Path Selection Process 34
Cost Community Support for Aggregate Routes and Multipaths 35
Influencing Route Preference in a Multiexit IGP Network 36
BGP Cost Community Support for EIGRP MPLS VPN PE-CE with Back-door
Links 37
Adding Routes to the Routing Information Base 38
BGP Best Path Algorithm 38
Comparing Pairs of Paths 39
Order of Comparisons 40
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Best Path Change Suppression 41
Administrative Distance 42
Multiprotocol BGP 43
Route Dampening 45
Minimizing Flapping 46
BGP Routing Domain Confederation 46
BGP Route Reflectors 46
Default Address Family for show Commands 50
MPLS VPN Carrier Supporting Carrier 50
BGP Keychains 51
BGP Nonstop Routing 51
BGP Local Label Retention 52
Command Line Interface (CLI) Consistency for BGP Commands 53
BGP Additional Paths 53
iBGP Multipath Load Sharing 53
BGP Selective Multipath 54
Accumulated Interior Gateway Protocol Attribute 56
Per VRF and Per CE Label for IPv6 Provider Edge 56
IPv4 BGP-Policy Accounting on Cisco ASR 9000's A9K-SIP-700 56
IPv6 Unicast Routing on Cisco ASR 9000's A9K-SIP-700 57
IPv6 uRPF Support on Cisco ASR 9000's A9K-SIP-700 57
Remove and Replace Private AS Numbers from AS Path in BGP 57
Selective VRF Download 58
Line Card Roles and Filters in Selective VRF Download 58
Selective VRF Download Disable 59
Calculating Routes Downloaded to Line Card with or without SVD 59
BGP Accept Own 61
BGP DMZ Link Bandwidth for Unequal Cost Recursive Load Balancing 63
BFD Multihop Support for BGP 63
BGP Multi-Instance and Multi-AS 63
BGP Prefix Origin Validation Based on RPKI 64
Configuring RPKI Cache-server 64
Configuring RPKI Prefix Validation 67
Configuring RPKI Bestpath Computation 68
BGP 3107 PIC Updates for Global Prefixes 69
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BGP Prefix Independent Convergence for RIB and FIB 70
BGP Update Message Error Handling 71
BGP Attribute Filtering 71
BGP Attribute Filter Actions 71
BGP Error Handling and Attribute Filtering Syslog Messages 72
BGP Link-State 72
BGP Permanent Network 73
BGP-RIB Feedback Mechanism for Update Generation 73
BGP VRF Dynamic Route Leaking 74
User Defined Martian Check 74
Resilient Per-CE Label Allocation Mode 75
How to Implement BGP 75
Enabling BGP Routing 75
Configuring Multiple BGP Instances for a Specific Autonomous System 78
Configuring a Routing Domain Confederation for BGP 78
Resetting an eBGP Session Immediately Upon Link Failure 79
Logging Neighbor Changes 80
Adjusting BGP Timers 80
Changing the BGP Default Local Preference Value 81
Configuring the MED Metric for BGP 82
Configuring BGP Weights 83
Tuning the BGP Best-Path Calculation 84
Indicating BGP Back-door Routes 85
Configuring Aggregate Addresses 86
Redistributing iBGP Routes into IGP 87
Redistributing Prefixes into Multiprotocol BGP 88
Configuring BGP Route Dampening 90
Applying Policy When Updating the Routing Table 95
Setting BGP Administrative Distance 96
Configuring a BGP Neighbor Group and Neighbors 96
Configuring a Route Reflector for BGP 99
Configuring BGP Route Filtering by Route Policy 100
Configuring BGP Attribute Filtering 102
Configuring BGP Next-Hop Trigger Delay 103
Disabling Next-Hop Processing on BGP Updates 104
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Configuring BGP Community and Extended-Community Advertisements 105
Configuring the BGP Cost Community 107
Configuring Software to Store Updates from a Neighbor 110
Configuring a VPN Routing and Forwarding Instance in BGP 112
Defining Virtual Routing and Forwarding Tables in Provider Edge Routers 112
Configuring the Route Distinguisher 114
Configuring PE-PE or PE-RR Interior BGP Sessions 115
Configuring Route Reflector to Hold Routes That Have a Defined Set of RT
Communities 118
Configuring BGP as a PE-CE Protocol 119
Redistribution of IGPs to BGP 123
Configuring Keychains for BGP 125
Disabling a BGP Neighbor 126
Resetting Neighbors Using BGP Inbound Soft Reset 127
Resetting Neighbors Using BGP Outbound Soft Reset 128
Resetting Neighbors Using BGP Hard Reset 129
Clearing Caches, Tables, and Databases 130
Displaying System and Network Statistics 131
Displaying BGP Process Information 132
Monitoring BGP Update Groups 134
Configuring BGP Nonstop Routing 135
Installing Primary Backup Path for Prefix Independent Convergence (PIC) 136
Retaining Allocated Local Label for Primary Path 137
Configuring BGP Additional Paths 138
Configuring iBGP Multipath Load Sharing 139
Originating Prefixes with AiGP 140
Configuring BGP Accept Own 142
Configuring BGP Link-State 143
Configuring BGP Link-state 143
Configuring Domain Distinguisher 144
Configuring BGP Permanent Network 145
Configuring BGP Permanent Network 145
How to Advertise Permanent Network 147
Enabling BGP Unequal Cost Recursive Load Balancing 148
Configuring VRF Dynamic Route Leaking 150
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Enabling Selective VRF Download 152
Disabling Selective VRF Download 154
Configuring Resilient Per-CE Label Allocation Mode 155
Configuring Resilient Per-CE Label Allocation Mode Under VRF Address Family 155
Configuring Resilient Per-CE Label Allocation Mode Using a Route-Policy 157
Configuration Examples for Implementing BGP 159
Enabling BGP: Example 159
Displaying BGP Update Groups: Example 160
BGP Neighbor Configuration: Example 161
BGP Confederation: Example 161
BGP Route Reflector: Example 163
BGP Nonstop Routing Configuration: Example 163
Primary Backup Path Installation: Example 164
Allocated Local Label Retention: Example 164
iBGP Multipath Loadsharing Configuration: Example 164
Originating Prefixes With AiGP: Example 164
BGP Accept Own Configuration: Example 165
BGP Unequal Cost Recursive Load Balancing: Example 165
VRF Dynamic Route Leaking Configuration: Example 167
Resilient Per-CE Label Allocation Mode Configuration: Example 168
Configuring Resilient Per-CE Label Allocation Mode Under VRF Address Family:
Example 168
Configuring Resilient Per-CE Label Allocation Mode Using a Route-Policy:
Example 168
Where to Go Next 168
Additional References 168
CHAPTER 3 Implementing BFD 173
Prerequisites for Implementing BFD 175
Restrictions for Implementing BFD 176
Information About BFD 177
Differences in BFD in Cisco IOS XR Software and Cisco IOS Software 177
BFD Multipath Sessions Support on nV Edge System 178
BFD Modes of Operation 178
BFD Packet Information 179
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BFD Source and Destination Ports 179
BFD Packet Intervals and Failure Detection 179
BFD Packet Intervals on Physical Interfaces 179
BFD Packet Intervals on Bundle Member Links 180
Control Packet Failure Detection In Asynchronous Mode 180
Echo Packet Failure Detection In Asynchronous Mode 180
Echo Failure Detection Examples 181
Summary of Packet Intervals and Failure Detection Times for BFD on Bundle
Interfaces 182
Echo Packet Latency 183
Priority Settings for BFD Packets 183
BFD for IPv4 184
Enabling BFD on a Static Route 185
BFD for IPv6 187
BFD on Bundled VLANs 187
BFD Over Member Links on Link Bundles 188
Overview of BFD State Change Behavior on Member Links and Bundle Status 188
BFD Multipath Sessions 190
BFD for MultiHop Paths 190
Setting up BFD Multihop 191
BFD over MPLS Traffic Engineering LSPs 191
Bidirectional Forwarding Detection over Logical Bundle 191
Bidirectional Forwarding Detection over Generic Routing Encapsulation 192
Bidirectional Forwarding Detection IPv6 Multihop 192
BFD over Pseudowire Headend 193
BFD over Satellite Interfaces 193
BFD over IRB 193
BFD over Bundle Per-Member Link 194
BFD Dampening 195
BFD Hardware Offload 195
BFD Object Tracking 196
How to Configure BFD 196
BFD Configuration Guidelines 196
Configuring BFD Under a Dynamic Routing Protocol or Using a Static Route 197
Enabling BFD on a BGP Neighbor 197
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Enabling BFD for OSPF on an Interface 199
Enabling BFD for OSPFv3 on an Interface 200
Enabling BFD on a Static Route 202
Configuring BFD on Bundle Member Links 204
Prerequisites for Configuring BFD on Bundle Menmber Links 204
Specifying the BFD Destination Address on a Bundle 204
Enabling BFD Sessions on Bundle Members 204
Configuring the Minimum Thresholds for Maintaining an Active Bundle 205
Configuring BFD Packet Transmission Intervals and Failure Detection Times on a
Bundle 206
Configuring Allowable Delays for BFD State Change Notifications Using Timers on
a Bundle 208
Enabling Echo Mode to Test the Forwarding Path to a BFD Peer 209
Overriding the Default Echo Packet Source Address 209
Specifying the Echo Packet Source Address Globally for BFD 209
Specifying the Echo Packet Source Address on an Individual Interface or Bundle 210
Configuring BFD Session Teardown Based on Echo Latency Detection 211
Delaying BFD Session Startup Until Verification of Echo Path and Latency 212
Disabling Echo Mode 213
Disabling Echo Mode on a Router 213
Disabling Echo Mode on an Individual Interface or Bundle 214
Minimizing BFD Session Flapping Using BFD Dampening 215
Enabling and Disabling IPv6 Checksum Support 216
Enabling and Disabling IPv6 Checksum Calculations for BFD on a Router 216
Enabling and Disabling IPv6 Checksum Calculations for BFD on an Individual Interface
or Bundle 217
Clearing and Displaying BFD Counters 218
Configuring Coexistence Between BFD over Bundle (BoB) and BFD over Logical Bundle
(BLB) 219
Configuring BFD IPv6 Multihop 220
Configuring BFD IPv6 Multihop for eBGP Neighbors 220
Configuring BFD IPv6 Multihop for iBGP Neighbors 221
Configuring BFD over MPLS Traffic Engineering LSPs 222
Enabling BFD Parameters for BFD over TE Tunnels 222
Configuring BFD Bring up Timeout 223
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Configuring BFD Dampening for TE Tunnels 224
Configuring Periodic LSP Ping Requests 225
Configuring BFD at the Tail End 226
Configuring BFD over LSP Sessions on Line Cards 227
Configuring BFD Object Tracking: 228
Configuration Examples for Configuring BFD 229
BFD Over BGP: Example 229
BFD Over OSPF: Examples 229
BFD Over Static Routes: Examples 230
BFD on Bundled VLANs: Example 230
BFD on Bundle Member Links: Examples 231
Echo Packet Source Address: Examples 232
Echo Latency Detection: Examples 233
Echo Startup Validation: Examples 233
BFD Echo Mode Disable: Examples 233
BFD Dampening: Examples 234
BFD IPv6 Checksum: Examples 234
BFD Peers on Routers Running Cisco IOS and Cisco IOS XR Software: Example 235
Configuring BFD IPv6 Multihop: Examples 235
BFD over MPLS TE LSPs: Examples 236
BFD over MPLS TE Tunnel Head-end Configuration: Example 236
BFD over MPLS TE Tunnel Tail-end Configuration: Example 236
Where to Go Next 236
Additional References 236
Related Documents 237
Standards 237
RFCs 237
MIBs 237
Technical Assistance 238
CHAPTER 4 Implementing EIGRP 239
Prerequisites for Implementing EIGRP 240
Restrictions for Implementing EIGRP 240
Information About Implementing EIGRP 240
EIGRP Functional Overview 240
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EIGRP Features 241
EIGRP Components 241
EIGRP Configuration Grouping 242
EIGRP Configuration Modes 242
EIGRP Interfaces 243
Redistribution for an EIGRP Process 244
Metric Weights for EIGRP Routing 244
Mismatched K Values 244
Goodbye Message 245
Percentage of Link Bandwidth Used for EIGRP Packets 245
Floating Summary Routes for an EIGRP Process 245
Split Horizon for an EIGRP Process 247
Adjustment of Hello Interval and Hold Time for an EIGRP Process 248
Stub Routing for an EIGRP Process 248
Route Policy Options for an EIGRP Process 249
EIGRP Layer 3 VPN PE-CE Site-of-Origin 250
Router Interoperation with the Site-of-Origin Extended Community 250
Route Manipulation using SoO match condition 251
EIGRP v4/v6 Authentication Using Keychain 252
EIGRP Wide Metric Computation 252
EIGRP Multi-Instance 253
How to Implement EIGRP 253
Enabling EIGRP Routing 253
Configuring Route Summarization for an EIGRP Process 255
Redistributing Routes for EIGRP 257
Creating a Route Policy and Attaching It to an EIGRP Process 259
Configuring Stub Routing for an EIGRP Process 260
Configuring EIGRP as a PE-CE Protocol 261
Redistributing BGP Routes into EIGRP 263
Monitoring EIGRP Routing 265
Configuring an EIGRP Authentication Keychain 267
Configuring an Authentication Keychain for an IPv4/IPv6 Interface on a Default
VRF 267
Configuring an Authentication Keychain for an IPv4/IPv6 Interface on a Nondefault
VRF 268
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Configuration Examples for Implementing EIGRP 269
Configuring a Basic EIGRP Configuration: Example 269
Configuring an EIGRP Stub Operation: Example 270
Configuring an EIGRP PE-CE Configuration with Prefix-Limits: Example 270
Configuring an EIGRP Authentication Keychain: Example 271
Additional References 271
CHAPTER 5 Implementing IS-IS 273
Prerequisites for Implementing IS-IS 273
Restrictions for Implementing IS-IS 273
Information About Implementing IS-IS 274
IS-IS Functional Overview 274
Key Features Supported in the Cisco IOS XR IS-IS Implementation 274
IS-IS Configuration Grouping 275
IS-IS Configuration Modes 275
Router Configuration Mode 275
Router Address Family Configuration Mode 275
Interface Configuration Mode 275
Interface Address Family Configuration Mode 276
IS-IS Interfaces 276
Multitopology Configuration 276
IPv6 Routing and Configuring IPv6 Addressing 276
Limit LSP Flooding 277
Flood Blocking on Specific Interfaces 277
Mesh Group Configuration 277
Maximum LSP Lifetime and Refresh Interval 277
Single-Topology IPv6 Support 278
Multitopology IPv6 for IS-IS 278
IS-IS Authentication 278
Nonstop Forwarding 279
Multi-Instance IS-IS 280
Multiprotocol Label Switching Traffic Engineering 280
Overload Bit on Router 280
Overload Bit Configuration During Multitopology Operation 281
IS-IS Overload Bit Avoidance 281
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Default Routes 281
Attached Bit on an IS-IS Instance 281
IS-IS Support for Route Tags 282
Multicast-Intact Feature 282
Multicast Topology Support Using IS-IS 282
MPLS Label Distribution Protocol IGP Synchronization 283
MPLS LDP-IGP Synchronization Compatibility with LDP Graceful Restart 283
MPLS LDP-IGP Synchronization Compatibility with IGP Nonstop Forwarding 283
Label Distribution Protocol IGP Auto-configuration 284
MPLS TE Forwarding Adjacency 284
MPLS TE Interarea Tunnels 284
IP Fast Reroute 284
Unequal Cost Multipath Load-balancing for IS-IS 285
Enabling IS-IS and Configuring Level 1 or Level 2 Routing 285
Configuring Single Topology for IS-IS 287
Configuring Multitopology Routing 291
Restrictions for Configuring Multitopology Routing 291
Information About Multitopology Routing 291
Configuring a Global Topology and Associating It with an Interface 292
Enabling an IS-IS Topology 293
Placing an Interface in a Topology in IS-IS 294
Configuring a Routing Policy 295
Configuring Multitopology for IS-IS 296
Controlling LSP Flooding for IS-IS 296
Configuring Nonstop Forwarding for IS-IS 300
Configuring Authentication for IS-IS 302
Configuring Keychains for IS-IS 303
Configuring MPLS Traffic Engineering for IS-IS 304
Tuning Adjacencies for IS-IS 306
Setting SPF Interval for a Single-Topology IPv4 and IPv6 Configuration 309
Customizing Routes for IS-IS 311
Configuring MPLS LDP IS-IS Synchronization 313
Enabling Multicast-Intact 314
Tagging IS-IS Interface Routes 315
Setting the Priority for Adding Prefixes to the RIB 317
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Configuring IP/LDP Fast Reroute 318
Configuring IS-IS Overload Bit Avoidance 320
ISIS Link Group 321
Configure Link Group Profile 322
Configure Link Group Interface 324
Configuration Examples for Implementing IS-IS 325
Configuring Single-Topology IS-IS for IPv6: Example 325
Configuring Multitopology IS-IS for IPv6: Example 326
Redistributing IS-IS Routes Between Multiple Instances: Example 326
Tagging Routes: Example 327
Configuring IS-IS Overload Bit Avoidance: Example 327
Where to Go Next 327
Additional References 328
CHAPTER 6 Implementing OSPF 331
Prerequisites for Implementing OSPF 332
Information About Implementing OSPF 333
OSPF Functional Overview 333
Key Features Supported in the Cisco IOS XR Software OSPF Implementation 334
Comparison of Cisco IOS XR Software OSPFv3 and OSPFv2 335
OSPF Hierarchical CLI and CLI Inheritance 335
OSPF Routing Components 336
Autonomous Systems 336
Areas 336
Backbone Area 337
Stub Area 337
Not-so-Stubby Area 337
Routers 337
Area Border Routers 337
Autonomous System Boundary Routers (ASBR) 338
Interior Routers 338
OSPF Process and Router ID 338
Supported OSPF Network Types 339
Route Authentication Methods for OSPF 339
Plain Text Authentication 339
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MD5 Authentication 339
Authentication Strategies 340
Key Rollover 340
Neighbors and Adjacency for OSPF 340
Designated Router (DR) for OSPF 340
Default Route for OSPF 341
Link-State Advertisement Types for OSPF Version 2 341
Link-State Advertisement Types for OSPFv3 342
Virtual Link and Transit Area for OSPF 343
Passive Interface 343
OSPFv2 Sham Link Support for MPLS VPN 344
OSPFv3 Sham Link Support for MPLS VPN 345
Graceful Restart Procedure over the Sham-link 346
ECMP and OSPFv3 Sham-link 346
OSPF SPF Prefix Prioritization 346
Route Redistribution for OSPF 347
OSPF Shortest Path First Throttling 347
Nonstop Forwarding for OSPF Version 2 348
Graceful Shutdown for OSPFv3 349
Modes of Graceful Restart Operation 349
Restart Mode 349
Helper Mode 350
Protocol Shutdown Mode 350
Protocol Restoration 351
Graceful Restart Requirements and Restrictions 351
Warm Standby and Nonstop Routing for OSPF Version 2 352
Warm Standby for OSPF Version 3 353
Multicast-Intact Support for OSPF 353
Load Balancing in OSPF Version 2 and OSPFv3 353
Multi-Area Adjacency for OSPF Version 2 354
Label Distribution Protocol IGP Auto-configuration for OSPF 354
OSPF Authentication Message Digest Management 355
GTSM TTL Security Mechanism for OSPF 355
Path Computation Element for OSPFv2 355
OSPF IP Fast Reroute Loop Free Alternate 356
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Management Information Base (MIB) for OSPFv3 356
VRF-lite Support for OSPFv2 357
OSPFv3 Timers Link-state Advertisements and Shortest Path First Throttle Default Values
Update 357
Unequal Cost Multipath Load-balancing for OSPF 357
How to Implement OSPF 358
Enabling OSPF 358
Configuring Stub and Not-So-Stubby Area Types 360
Configuring Neighbors for Nonbroadcast Networks 362
Configuring Authentication at Different Hierarchical Levels for OSPF Version 2 366
Controlling the Frequency That the Same LSA Is Originated or Accepted for OSPF 369
Creating a Virtual Link with MD5 Authentication to Area 0 for OSPF 371
Examples 374
Summarizing Subnetwork LSAs on an OSPF ABR 375
Redistribute Routes into OSPF 377
Configuring OSPF Shortest Path First Throttling 379
Examples 381
Configuring Nonstop Forwarding Specific to Cisco for OSPF Version 2 381
Configuring OSPF Version 2 for MPLS Traffic Engineering 383
Examples 385
Configuring OSPFv3 Graceful Restart 387
Displaying Information About Graceful Restart 388
Configuring an OSPFv2 Sham Link 389
Enabling Nonstop Routing for OSPFv2 392
Enabling Nonstop Routing for OSPFv3 393
Configuring OSPF SPF Prefix Prioritization 393
Enabling Multicast-intact for OSPFv2 395
Associating Interfaces to a VRF 395
Configuring OSPF as a Provider Edge to Customer Edge (PE-CE) Protocol 397
Creating Multiple OSPF Instances (OSPF Process and a VRF) 399
Configuring Multi-area Adjacency 400
Configuring Label Distribution Protocol IGP Auto-configuration for OSPF 402
Configuring LDP IGP Synchronization: OSPF 403
Configuring Authentication Message Digest Management for OSPF 404
Examples 405
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Configuring Generalized TTL Security Mechanism (GTSM) for OSPF 406
Examples 408
Verifying OSPF Configuration and Operation 408
Configuring IP Fast Reroute Loop-free Alternate 411
Enabling IPFRR LFA 411
Excluding an Interface From IP Fast Reroute Per-link Computation 412
Enabling OSPF Interaction with SRMS Server 412
Configuration Examples for Implementing OSPF 414
Cisco IOS XR Software for OSPF Version 2 Configuration: Example 414
CLI Inheritance and Precedence for OSPF Version 2: Example 415
MPLS TE for OSPF Version 2: Example 416
ABR with Summarization for OSPFv3: Example 416
ABR Stub Area for OSPFv3: Example 417
ABR Totally Stub Area for OSPFv3: Example 417
Configuring OSPF SPF Prefix Prioritization: Example 417
Route Redistribution for OSPFv3: Example 418
Virtual Link Configured Through Area 1 for OSPFv3: Example 418
Virtual Link Configured with MD5 Authentication for OSPF Version 2: Example 419
VPN Backbone and Sham Link Configured for OSPF Version 2: Example 420
Where to Go Next 421
Additional References 421
CHAPTER 7 Implementing and Monitoring RIB 425
Prerequisites for Implementing RIB 426
Information About RIB Configuration 426
Overview of RIB 426
RIB Data Structures in BGP and Other Protocols 426
RIB Administrative Distance 427
RIB Support for IPv4 and IPv6 427
RIB Statistics 428
IPv6 Provider Edge IPv6 and IPv6 VPN Provider Edge Transport over MPLS 428
RIB Quarantining 428
Route and Label Consistency Checker 429
How to Deploy and Monitor RIB 430
Verifying RIB Configuration Using the Routing Table 430
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Verifying Networking and Routing Problems 431
Disabling RIB Next-hop Dampening 432
Configuring RCC and LCC 433
Enabling RCC and LCC On-demand Scan 433
Enabling RCC and LCC Background Scan 434
BGP-RIB Feedback Mechanism for Update Generation 436
Configuration Examples for RIB Monitoring 436
Output of show route Command: Example 436
Output of show route backup Command: Example 437
Output of show route best-local Command: Example 437
Output of show route connected Command: Example 437
Output of show route local Command: Example 438
Output of show route longer-prefixes Command: Example 438
Output of show route next-hop Command: Example 438
Enabling RCC and LCC: Example 439
Where to Go Next 439
Additional References 440
CHAPTER 8 Implementing RIP 443
Prerequisites for Implementing RIP 444
Information About Implementing RIP 444
RIP Functional Overview 444
Split Horizon for RIP 445
Route Timers for RIP 445
Route Redistribution for RIP 446
Default Administrative Distances for RIP 446
Routing Policy Options for RIP 447
Authentication Using Keychain in RIP 447
In-bound RIP Traffic on an Interface 448
Out-bound RIP Traffic on an Interface 449
How to Implement RIP 449
Enabling RIP 449
Customizing RIP 451
Control Routing Information 453
Creating a Route Policy for RIP 455
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Contents

Configuring RIP Authentication Keychain 456
Configuring RIP Authentication Keychain for IPv4 Interface on a Non-default
VRF 456
Configuring RIP Authentication Keychain for IPv4 Interface on Default VRF 458
Configuration Examples for Implementing RIP 459
Configuring a Basic RIP Configuration: Example 459
Configuring RIP on the Provider Edge: Example 459
Adjusting RIP Timers for each VRF Instance: Example 460
Configuring Redistribution for RIP: Example 460
Configuring Route Policies for RIP: Example 461
Configuring Passive Interfaces and Explicit Neighbors for RIP: Example 461
Controlling RIP Routes: Example 462
Configuring RIP Authentication Keychain: Example 462
Additional References 462
CHAPTER 9 Implementing Routing Policy 465
Prerequisites for Implementing Routing Policy 466
Restrictions for Implementing Routing Policy 466
Information About Implementing Routing Policy 467
Routing Policy Language 467
Routing Policy Language Overview 467
Routing Policy Language Structure 468
Names 468
Sets 468
as-path-set 469
community-set 470
extcommunity-set 471
prefix-set 474
ACL Support in RPL Prefix Sets 476
rd-set 476
Routing Policy Language Components 476
Routing Policy Language Usage 477
RPL Variables 479
Routing Policy Configuration Basics 479
Policy Definitions 479
Cisco ASR 9000 Series Aggregation Services Router Routing Configuration Guide, Release 5.1.x
xx OL-30423-03
Contents