Cisco ASR 9000 Series User manual

Cisco ASR 9000 Series Aggregation Services Router Routing
Configuration Guide, Release 5.3.x
First Published: 2015-01-12
Last Modified: 2015-09-03
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CONTENTS
Preface Preface xxix
Obtaining Documentation and Submitting a Service Request xxix
CHAPTER 1 New and Changed Routing Features 1
New and Changed Routing Feature Information 1
CHAPTER 2 Implementing BGP 5
Prerequisites for Implementing BGP 7
Information About Implementing BGP 8
BGP Functional Overview 8
BGP Router Identifier 8
BGP Maximum Prefix - Discard Extra Paths 9
Restrictions 9
BGP Default Limits 10
BGP Next Hop Tracking 11
Scoped IPv4/VPNv4 Table Walk 12
Reordered Address Family Processing 12
New Thread for Next-Hop Processing 12
show, clear, and debug Commands 12
Autonomous System Number Formats in BGP 13
2-byte Autonomous System Number Format 13
4-byte Autonomous System Number Format 13
as-format Command 13
BGP Configuration 13
Configuration Modes 14
Router Configuration Mode 14
Router Address Family Configuration Mode 14
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Neighbor Configuration Mode 14
Neighbor Address Family Configuration Mode 14
VRF Configuration Mode 14
VRF Address Family Configuration Mode 15
Configuring Resilient Per-CE Label Allocation Mode Under VRF Address
Family 15
Configuring Resilient Per-CE Label Allocation Mode Using a
Route-Policy 17
VRF Neighbor Configuration Mode 18
VRF Neighbor Address Family Configuration Mode 18
VPNv4 Address Family Configuration Mode 18
L2VPN Address Family Configuration Mode 19
Neighbor Submode 19
Configuration Templates 20
Template Inheritance Rules 21
Viewing Inherited Configurations 24
show bgp neighbors 25
show bgp af-group 26
show bgp session-group 27
show bgp neighbor-group 28
No Default Address Family 29
Neighbor Address Family Combinations 29
Routing Policy Enforcement 30
Table Policy 31
Update Groups 32
BGP Update Generation and Update Groups 32
BGP Update Group 32
BGP Cost Community 32
How BGP Cost Community Influences the Best Path Selection Process 33
Cost Community Support for Aggregate Routes and Multipaths 34
Influencing Route Preference in a Multiexit IGP Network 35
BGP Cost Community Support for EIGRP MPLS VPN PE-CE with Back-door
Links 36
Adding Routes to the Routing Information Base 37
BGP DMZ Aggregate Bandwidth 37
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Configuring BGP DMZ Aggregate Bandwidth: Example 38
Configuring Policy-based Link Bandwidth: Example 39
BGP Best Path Algorithm 39
Comparing Pairs of Paths 40
Order of Comparisons 42
Best Path Change Suppression 42
Administrative Distance 43
Multiprotocol BGP 44
Route Dampening 46
Minimizing Flapping 47
BGP Routing Domain Confederation 47
BGP Route Reflectors 47
RPL - if prefix is-best-path/is-best-multipath 51
Default Address Family for show Commands 52
TCP Maximum Segment Size 52
Per Neighbor TCP MSS 52
MPLS VPN Carrier Supporting Carrier 53
BGP Keychains 54
BGP Nonstop Routing 54
BGP Local Label Retention 55
Command Line Interface (CLI) Consistency for BGP Commands 55
BGP Additional Paths 56
iBGP Multipath Load Sharing 56
BGP Selective Multipath 57
Accumulated Interior Gateway Protocol Attribute 58
Per VRF and Per CE Label for IPv6 Provider Edge 59
IPv4 BGP-Policy Accounting on Cisco ASR 9000's A9K-SIP-700 59
IPv6 Unicast Routing on Cisco ASR 9000's A9K-SIP-700 59
IPv6 uRPF Support on Cisco ASR 9000's A9K-SIP-700 60
Remove and Replace Private AS Numbers from AS Path in BGP 60
Selective VRF Download 61
Line Card Roles and Filters in Selective VRF Download 61
Selective VRF Download Disable 62
Calculating Routes Downloaded to Line Card with or without SVD 62
BGP Accept Own 63
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BGP DMZ Link Bandwidth for Unequal Cost Recursive Load Balancing 65
BFD Multihop Support for BGP 65
BGP Multi-Instance and Multi-AS 65
BGP Prefix Origin Validation Based on RPKI 66
Configuring RPKI Cache-server 66
Configuring RPKI Prefix Validation 69
Configuring RPKI Bestpath Computation 70
BGP 3107 PIC Updates for Global Prefixes 71
BGP Prefix Independent Convergence for RIB and FIB 72
BGP Update Message Error Handling 72
BGP Attribute Filtering 73
BGP Attribute Filter Actions 73
BGP Error Handling and Attribute Filtering Syslog Messages 73
BGP Link-State 74
BGP Permanent Network 74
BGP-RIB Feedback Mechanism for Update Generation 75
BGP VRF Dynamic Route Leaking 75
User Defined Martian Check 76
Resilient Per-CE Label Allocation Mode 77
BGP Multipath Enhancements 77
MVPN with BGP SAFI-2 and SAFI-129 77
BGP Monitoring Protocol 78
How to Implement BGP 79
Enabling BGP Routing 79
Configuring Multiple BGP Instances for a Specific Autonomous System 81
Configuring a Routing Domain Confederation for BGP 82
Resetting an eBGP Session Immediately Upon Link Failure 83
Logging Neighbor Changes 84
Adjusting BGP Timers 84
Changing the BGP Default Local Preference Value 85
Configuring the MED Metric for BGP 86
Configuring BGP Weights 86
Tuning the BGP Best-Path Calculation 88
Indicating BGP Back-door Routes 89
Configuring Aggregate Addresses 90
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Redistributing iBGP Routes into IGP 91
Configuring Discard Extra Paths 92
Configuring Per Neighbor TCP MSS 93
Disabling Per Neighbor TCP MSS 95
Redistributing Prefixes into Multiprotocol BGP 98
Configuring BGP Route Dampening 100
Applying Policy When Updating the Routing Table 105
Setting BGP Administrative Distance 106
Configuring a BGP Neighbor Group and Neighbors 106
Configuring a Route Reflector for BGP 109
Configuring BGP Route Filtering by Route Policy 110
Configuring BGP Attribute Filtering 112
Configuring BGP Next-Hop Trigger Delay 113
Disabling Next-Hop Processing on BGP Updates 114
Configuring BGP Community and Extended-Community Advertisements 115
Configuring the BGP Cost Community 117
Configuring Software to Store Updates from a Neighbor 120
BGP Persistence 122
BGP Persistence Configuration: Example 123
BGP Graceful Maintenance 123
Restrictions for BGP Graceful Maintenance 123
Graceful Maintenance Operation 124
Inter Autonomous System 124
No Automatic Shutdown 125
When to Shut Down After Graceful Maintenance 125
Activate Graceful Maintenance under BGP Router (All Neighbors) 125
Activate Graceful Maintenance on a Single Neighbor 127
Activate Graceful Maintenance on a Group of Neighbors 127
Direct Router to Reduce Route Preference 129
Bring Router or Link Back into Service 130
Show Command Outputs to Verify BGP Graceful Maintenance 130
L3VPN iBGP PE-CE 131
L3VPN iBGP PE-CE Overview 131
Restrictions for L3VPN iBGP PE-CE 132
Configuring L3VPN iBGP PE-CE 133
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Flow-tag propagation 135
Restrictions for flow-tag propagation 135
Source and destination-based flow tag 135
Configure Source and Destination-based Flow Tag 135
Configuring a VPN Routing and Forwarding Instance in BGP 137
Defining Virtual Routing and Forwarding Tables in Provider Edge Routers 137
Configuring the Route Distinguisher 139
Configuring PE-PE or PE-RR Interior BGP Sessions 140
Configuring Route Reflector to Hold Routes That Have a Defined Set of RT
Communities 143
Configuring BGP as a PE-CE Protocol 144
Redistribution of IGPs to BGP 148
Configuring Keychains for BGP 150
Disabling a BGP Neighbor 151
Resetting Neighbors Using BGP Inbound Soft Reset 152
Resetting Neighbors Using BGP Outbound Soft Reset 153
Resetting Neighbors Using BGP Hard Reset 154
Clearing Caches, Tables, and Databases 155
Displaying System and Network Statistics 156
Displaying BGP Process Information 157
Monitoring BGP Update Groups 159
Configuring BGP Nonstop Routing 160
Disable BGP Nonstop Routing 160
Re-enable BGP Nonstop Routing 161
Installing Primary Backup Path for Prefix Independent Convergence (PIC) 161
Retaining Allocated Local Label for Primary Path 163
Configuring BGP Additional Paths 163
Configuring iBGP Multipath Load Sharing 165
Originating Prefixes with AiGP 166
Configuring BGP Accept Own 168
Configuring BGP Link-State 169
Configuring BGP Link-state 169
Configuring Domain Distinguisher 170
Configuring BGP Permanent Network 171
Configuring BGP Permanent Network 171
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How to Advertise Permanent Network 173
Enabling BGP Unequal Cost Recursive Load Balancing 174
Configuring VRF Dynamic Route Leaking 176
Enabling Selective VRF Download 177
Disabling Selective VRF Download 179
Configuring Resilient Per-CE Label Allocation Mode 181
Configuring Resilient Per-CE Label Allocation Mode Under VRF Address Family 181
Configuring Resilient Per-CE Label Allocation Mode Using a Route-Policy 183
Configuration Examples for Implementing BGP 184
Enabling BGP: Example 184
Displaying BGP Update Groups: Example 186
BGP Neighbor Configuration: Example 186
BGP Confederation: Example 187
BGP Route Reflector: Example 188
BGP Nonstop Routing Configuration: Example 189
Primary Backup Path Installation: Example 189
Allocated Local Label Retention: Example 189
iBGP Multipath Loadsharing Configuration: Example 189
Discard Extra Paths Configuration: Example 190
Displaying Discard Extra Paths Information: Example 190
Configure Per Neighbor TCP MSS: Examples 191
Verify Per Neighbor TCP MSS: Examples 192
Originating Prefixes With AiGP: Example 194
BGP Accept Own Configuration: Example 195
BGP Unequal Cost Recursive Load Balancing: Example 195
VRF Dynamic Route Leaking Configuration: Example 197
Resilient Per-CE Label Allocation Mode Configuration: Example 198
Configuring Resilient Per-CE Label Allocation Mode Under VRF Address Family:
Example 198
Configuring Resilient Per-CE Label Allocation Mode Using a Route-Policy: Example 198
Where to Go Next 198
Additional References 198
CHAPTER 3 Implementing BGP Flowspec 203
BGP Flow Specification 203
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Limitations 204
BGP Flowspec Conceptual Architecture 204
Information About Implementing BGP Flowspec 205
Flow Specifications 206
Supported Matching Criteria and Actions 206
Traffic Filtering Actions 209
BGP Flowspec Client-Server (Controller) Model and Configuration 211
How to Configure BGP Flowspec 212
Enable Flowspec on BGP Side 213
Define Class 214
Define Policy Map 215
Link Flowspec to PBR Policies 217
Verify BGP Flowspec 219
Preserving Redirect Nexthop 221
Validate BGP Flowspec 222
Disabling BGP Flowspec 223
Disable Flowspec Redirect and Validation 223
Configuration Examples for Implementing BGP Flowspec 225
Flowspec Rule Configuration 225
Drop Packet Length 226
Remark DSCP 226
Additional References for BGP Flowspec 227
CHAPTER 4 Implementing BFD 229
Prerequisites for Implementing BFD 231
Restrictions for Implementing BFD 232
Information About BFD 233
Differences in BFD in Cisco IOS XR Software and Cisco IOS Software 233
BFD Multipath Sessions Support on nV Edge System 234
BFD Modes of Operation 234
BFD Packet Information 235
BFD Source and Destination Ports 235
BFD Packet Intervals and Failure Detection 235
BFD Packet Intervals on Physical Interfaces 235
BFD Packet Intervals on Bundle Member Links 236
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Control Packet Failure Detection In Asynchronous Mode 236
Echo Packet Failure Detection In Asynchronous Mode 236
Echo Failure Detection Examples 237
Summary of Packet Intervals and Failure Detection Times for BFD on Bundle
Interfaces 238
Echo Packet Latency 239
Priority Settings for BFD Packets 239
BFD for IPv4 240
Enabling BFD on a Static Route 241
BFD for IPv6 243
BFD on Bundled VLANs 243
BFD Over Member Links on Link Bundles 244
Overview of BFD State Change Behavior on Member Links and Bundle Status 244
BFD Multipath Sessions 246
BFD for MultiHop Paths 246
Setting up BFD Multihop 247
BFD over MPLS Traffic Engineering LSPs 247
Echo Timer configuration for BFD on Bundle Interfaces 247
Bidirectional Forwarding Detection over Logical Bundle 249
Bidirectional Forwarding Detection over Generic Routing Encapsulation 249
Bidirectional Forwarding Detection IPv6 Multihop 249
BFD over Pseudowire Headend 250
BFD over Satellite Interfaces 250
BFD over IRB 251
BFD over Bundle Per-Member Link 251
BFD over Bundles CISCO/IETF Mode Support on a Per Bundle Basis 252
BFD Dampening 252
BFD Hardware Offload 253
BFD Object Tracking 254
How to Configure BFD 254
BFD Configuration Guidelines 254
Configuring BFD Under a Dynamic Routing Protocol or Using a Static Route 255
Enabling BFD on a BGP Neighbor 255
Enabling BFD for OSPF on an Interface 256
Enabling BFD for OSPFv3 on an Interface 258
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Enabling BFD on a Static Route 260
Configuring BFD on Bundle Member Links 261
Prerequisites for Configuring BFD on Bundle Menmber Links 261
Specifying the BFD Destination Address on a Bundle 262
Enabling BFD Sessions on Bundle Members 262
Configuring the Minimum Thresholds for Maintaining an Active Bundle 263
Configuring BFD Packet Transmission Intervals and Failure Detection Times on a
Bundle 264
Configuring Allowable Delays for BFD State Change Notifications Using Timers on
a Bundle 266
Configuring BFD over Bundle per Member Mode 267
Configure BFD over Bundles CISCO/IETF Mode Support on a Per Bundle Basis 268
Enabling Echo Mode to Test the Forwarding Path to a BFD Peer 270
Overriding the Default Echo Packet Source Address 271
Specifying the Echo Packet Source Address Globally for BFD 271
Specifying the Echo Packet Source Address on an Individual Interface or Bundle 272
Configuring BFD Session Teardown Based on Echo Latency Detection 272
Delaying BFD Session Startup Until Verification of Echo Path and Latency 273
Disabling Echo Mode 274
Disabling Echo Mode on a Router 275
Disabling Echo Mode on an Individual Interface or Bundle 275
Minimizing BFD Session Flapping Using BFD Dampening 276
Enabling and Disabling IPv6 Checksum Support 277
Enabling and Disabling IPv6 Checksum Calculations for BFD on a Router 277
Enabling and Disabling IPv6 Checksum Calculations for BFD on an Individual Interface
or Bundle 278
Clearing and Displaying BFD Counters 279
Configuring Coexistence Between BFD over Bundle (BoB) and BFD over Logical Bundle
(BLB) 280
Configuring BFD IPv6 Multihop 281
Configuring BFD IPv6 Multihop for eBGP Neighbors 281
Configuring BFD IPv6 Multihop for iBGP Neighbors 282
Configuring BFD over MPLS Traffic Engineering LSPs 283
Enabling BFD Parameters for BFD over TE Tunnels 283
Configuring BFD Bring up Timeout 284
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Configuring BFD Dampening for TE Tunnels 285
Configuring Periodic LSP Ping Requests 286
Configuring BFD at the Tail End 287
Configuring BFD over LSP Sessions on Line Cards 288
Configuring BFD Object Tracking: 289
Configuration Examples for Configuring BFD 290
BFD Over BGP: Example 290
BFD Over OSPF: Examples 291
BFD Over Static Routes: Examples 291
BFD on Bundled VLANs: Example 292
BFD on Bundle Member Links: Examples 292
Echo Packet Source Address: Examples 293
Echo Latency Detection: Examples 294
Echo Startup Validation: Examples 294
BFD Echo Mode Disable: Examples 295
BFD Dampening: Examples 295
BFD IPv6 Checksum: Examples 295
BFD Peers on Routers Running Cisco IOS and Cisco IOS XR Software: Example 296
Configuring BFD IPv6 Multihop: Examples 296
BFD over MPLS TE LSPs: Examples 297
BFD over MPLS TE Tunnel Head-end Configuration: Example 297
BFD over MPLS TE Tunnel Tail-end Configuration: Example 297
Where to Go Next 297
Additional References 298
Related Documents 298
Standards 298
RFCs 298
MIBs 299
Technical Assistance 299
CHAPTER 5 Implementing EIGRP 301
Prerequisites for Implementing EIGRP 302
Restrictions for Implementing EIGRP 302
Information About Implementing EIGRP 302
EIGRP Functional Overview 302
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EIGRP Features 303
EIGRP Components 303
EIGRP Configuration Grouping 304
EIGRP Configuration Modes 304
EIGRP Interfaces 305
Redistribution for an EIGRP Process 306
Metric Weights for EIGRP Routing 306
Mismatched K Values 306
Goodbye Message 307
Percentage of Link Bandwidth Used for EIGRP Packets 307
Floating Summary Routes for an EIGRP Process 307
Split Horizon for an EIGRP Process 309
Adjustment of Hello Interval and Hold Time for an EIGRP Process 310
Stub Routing for an EIGRP Process 310
Route Policy Options for an EIGRP Process 311
EIGRP Layer 3 VPN PE-CE Site-of-Origin 312
Router Interoperation with the Site-of-Origin Extended Community 312
Route Manipulation using SoO match condition 313
EIGRP v4/v6 Authentication Using Keychain 314
EIGRP Wide Metric Computation 314
EIGRP Multi-Instance 315
EIGRP Support for BFD 315
How to Implement EIGRP 315
Enabling EIGRP Routing 315
Configuring Route Summarization for an EIGRP Process 317
Redistributing Routes for EIGRP 319
Creating a Route Policy and Attaching It to an EIGRP Process 321
Configuring Stub Routing for an EIGRP Process 322
Configuring EIGRP as a PE-CE Protocol 323
Redistributing BGP Routes into EIGRP 325
Monitoring EIGRP Routing 327
Configuring an EIGRP Authentication Keychain 329
Configuring an Authentication Keychain for an IPv4/IPv6 Interface on a Default
VRF 329
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Configuring an Authentication Keychain for an IPv4/IPv6 Interface on a Nondefault
VRF 330
Configuring unicast neighbors 331
Remote Neighbor Session Policy 332
Understanding Neighbor Terms 333
Remote Unicast-Listen (Point-to-Point) Neighbors 334
Restrictions for remote neighbors 334
Inheritance and precedence of the remote neighbor configurations 335
How to configure remote unicast neighbors 335
Configuration Examples for Implementing EIGRP 336
Configuring a Basic EIGRP Configuration: Example 337
Configuring an EIGRP Stub Operation: Example 337
Configuring an EIGRP PE-CE Configuration with Prefix-Limits: Example 337
Configuring an EIGRP Authentication Keychain: Example 338
Additional References 338
CHAPTER 6 Implementing IS-IS 341
Prerequisites for Implementing IS-IS 341
Restrictions for Implementing IS-IS 341
Information About Implementing IS-IS 342
IS-IS Functional Overview 342
Key Features Supported in the Cisco IOS XR IS-IS Implementation 342
IS-IS Configuration Grouping 343
IS-IS Configuration Modes 343
Router Configuration Mode 343
Router Address Family Configuration Mode 343
Interface Configuration Mode 343
Interface Address Family Configuration Mode 344
IS-IS Interfaces 344
Multitopology Configuration 344
IPv6 Routing and Configuring IPv6 Addressing 344
Limit LSP Flooding 345
Flood Blocking on Specific Interfaces 345
Mesh Group Configuration 345
Maximum LSP Lifetime and Refresh Interval 345
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Single-Topology IPv6 Support 346
Multitopology IPv6 for IS-IS 346
IS-IS Authentication 346
Nonstop Forwarding 347
ISIS NSR 348
Multi-Instance IS-IS 348
Multiprotocol Label Switching Traffic Engineering 348
Overload Bit on Router 348
Overload Bit Configuration During Multitopology Operation 349
IS-IS Overload Bit Avoidance 349
Default Routes 349
Attached Bit on an IS-IS Instance 350
IS-IS Support for Route Tags 350
Multicast-Intact Feature 350
Multicast Topology Support Using IS-IS 351
MPLS Label Distribution Protocol IGP Synchronization 351
MPLS LDP-IGP Synchronization Compatibility with LDP Graceful Restart 351
MPLS LDP-IGP Synchronization Compatibility with IGP Nonstop Forwarding 352
Label Distribution Protocol IGP Auto-configuration 352
MPLS TE Forwarding Adjacency 352
MPLS TE Interarea Tunnels 352
IP Fast Reroute 353
Unequal Cost Multipath Load-balancing for IS-IS 353
Enabling IS-IS and Configuring Level 1 or Level 2 Routing 354
Configuring Single Topology for IS-IS 355
Configuring Multitopology Routing 359
Restrictions for Configuring Multitopology Routing 359
Information About Multitopology Routing 360
Configuring a Global Topology and Associating It with an Interface 360
Enabling an IS-IS Topology 361
Placing an Interface in a Topology in IS-IS 362
Configuring a Routing Policy 363
Configuring Multitopology for IS-IS 364
Controlling LSP Flooding for IS-IS 364
Configuring Nonstop Forwarding for IS-IS 368
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Configuring ISIS-NSR 370
Configuring Authentication for IS-IS 371
Configuring Keychains for IS-IS 373
Configuring MPLS Traffic Engineering for IS-IS 374
Tuning Adjacencies for IS-IS 376
Setting SPF Interval for a Single-Topology IPv4 and IPv6 Configuration 379
Customizing Routes for IS-IS 381
Configuring MPLS LDP IS-IS Synchronization 383
Enabling Multicast-Intact 384
Tagging IS-IS Interface Routes 385
Setting the Priority for Adding Prefixes to the RIB 387
Configuring IP Fast Reroute Loop-free Alternate 388
Configuring IS-IS Overload Bit Avoidance 389
ISIS Link Group 390
Configure Link Group Profile 391
Configure Link Group Interface 393
Configuration Examples for Implementing IS-IS 394
Configuring Single-Topology IS-IS for IPv6: Example 394
Configuring Multitopology IS-IS for IPv6: Example 395
Redistributing IS-IS Routes Between Multiple Instances: Example 395
Tagging Routes: Example 396
Configuring IS-IS Overload Bit Avoidance: Example 396
Example: Configuring IS-IS To Handle Router Overload 396
Where to Go Next 402
Additional References 402
CHAPTER 7 Implementing OSPF 405
Prerequisites for Implementing OSPF 406
Information About Implementing OSPF 407
OSPF Functional Overview 407
Key Features Supported in the Cisco IOS XR Software OSPF Implementation 408
Comparison of Cisco IOS XR Software OSPFv3 and OSPFv2 409
OSPF Hierarchical CLI and CLI Inheritance 409
OSPF Routing Components 410
Autonomous Systems 410
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Areas 411
Backbone Area 411
Stub Area 411
Not-so-Stubby Area 411
Routers 412
Area Border Routers 412
Autonomous System Boundary Routers (ASBR) 412
Interior Routers 412
OSPF Process and Router ID 412
Supported OSPF Network Types 413
Route Authentication Methods for OSPF 413
Plain Text Authentication 413
MD5 Authentication 413
Authentication Strategies 414
Key Rollover 414
Neighbors and Adjacency for OSPF 414
OSPF strict-mode Support for BFD Dampening 414
Enabling strict-mode 415
BFD strict-mode: Example 416
OSPF FIB Download Notification 417
Designated Router (DR) for OSPF 417
Default Route for OSPF 417
Link-State Advertisement Types for OSPF Version 2 417
Link-State Advertisement Types for OSPFv3 418
Virtual Link and Transit Area for OSPF 419
Passive Interface 420
OSPFv2 Sham Link Support for MPLS VPN 420
OSPFv3 Sham Link Support for MPLS VPN 422
Graceful Restart Procedure over the Sham-link 423
ECMP and OSPFv3 Sham-link 423
OSPF SPF Prefix Prioritization 423
Route Redistribution for OSPF 424
OSPF Shortest Path First Throttling 424
Nonstop Forwarding for OSPF Version 2 425
Graceful Shutdown for OSPFv3 426
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Modes of Graceful Restart Operation 426
Restart Mode 426
Helper Mode 427
Protocol Shutdown Mode 427
Protocol Restoration 428
Graceful Restart Requirements and Restrictions 428
Warm Standby and Nonstop Routing for OSPF Version 2 429
Warm Standby for OSPF Version 3 430
Multicast-Intact Support for OSPF 430
Load Balancing in OSPF Version 2 and OSPFv3 430
Multi-Area Adjacency for OSPF Version 2 431
Label Distribution Protocol IGP Auto-configuration for OSPF 431
OSPF Authentication Message Digest Management 432
GTSM TTL Security Mechanism for OSPF 432
Path Computation Element for OSPFv2 432
OSPF IP Fast Reroute Loop Free Alternate 433
Management Information Base (MIB) for OSPFv3 433
VRF-lite Support for OSPFv2 434
OSPFv3 Timers Link-state Advertisements and Shortest Path First Throttle Default Values
Update 434
Unequal Cost Multipath Load-balancing for OSPF 434
How to Implement OSPF 435
Enabling OSPF 435
Configuring Stub and Not-So-Stubby Area Types 437
Configuring Neighbors for Nonbroadcast Networks 439
Configuring Authentication at Different Hierarchical Levels for OSPF Version 2 443
Controlling the Frequency That the Same LSA Is Originated or Accepted for OSPF 446
Creating a Virtual Link with MD5 Authentication to Area 0 for OSPF 448
Examples 451
Summarizing Subnetwork LSAs on an OSPF ABR 452
Redistribute Routes into OSPF 454
Configuring OSPF Shortest Path First Throttling 456
Examples 458
Configuring Nonstop Forwarding Specific to Cisco for OSPF Version 2 458
Configuring OSPF Version 2 for MPLS Traffic Engineering 460
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Examples 462
Configuring OSPFv3 Graceful Restart 464
Displaying Information About Graceful Restart 465
Configuring an OSPFv2 Sham Link 466
Enabling Nonstop Routing for OSPFv2 469
Enabling Nonstop Routing for OSPFv3 470
Configuring OSPF SPF Prefix Prioritization 470
Enabling Multicast-intact for OSPFv2 472
Associating Interfaces to a VRF 472
Configuring OSPF as a Provider Edge to Customer Edge (PE-CE) Protocol 474
Creating Multiple OSPF Instances (OSPF Process and a VRF) 476
Configuring Multi-area Adjacency 477
Configuring Label Distribution Protocol IGP Auto-configuration for OSPF 479
Configuring LDP IGP Synchronization: OSPF 480
Configuring Authentication Message Digest Management for OSPF 481
Examples 482
Configuring Generalized TTL Security Mechanism (GTSM) for OSPF 483
Examples 485
Verifying OSPF Configuration and Operation 485
Configuring IP Fast Reroute Loop-free Alternate 488
Enabling IPFRR LFA 488
Excluding an Interface From IP Fast Reroute Per-link Computation 489
Enabling OSPF Interaction with SRMS Server 489
Configuration Examples for Implementing OSPF 491
Cisco IOS XR Software for OSPF Version 2 Configuration: Example 491
CLI Inheritance and Precedence for OSPF Version 2: Example 492
MPLS TE for OSPF Version 2: Example 493
ABR with Summarization for OSPFv3: Example 493
ABR Stub Area for OSPFv3: Example 494
ABR Totally Stub Area for OSPFv3: Example 494
Configuring OSPF SPF Prefix Prioritization: Example 494
Route Redistribution for OSPFv3: Example 495
Virtual Link Configured Through Area 1 for OSPFv3: Example 495
Virtual Link Configured with MD5 Authentication for OSPF Version 2: Example 496
VPN Backbone and Sham Link Configured for OSPF Version 2: Example 497
Cisco ASR 9000 Series Aggregation Services Router Routing Configuration Guide, Release 5.3.x
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