Cisco Catalyst 9500 Series User manual

Routing Configuration Guide, Cisco IOS XE Everest 16.6.x (Catalyst
9500 Switches)
First Published: 2017-07-31
Last Modified: 2017-11-03
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©2017 Cisco Systems, Inc. All rights reserved.

CONTENTS
CHAPTER 1 Configuring Bidirectional Forwarding Detection 1
Bidirectional Forwarding Detection 1
Finding Feature Information 1
Prerequisites for Bidirectional Forwarding Detection 1
Restrictions for Bidirectional Forwarding Detection 2
Information About Bidirectional Forwarding Detection 2
BFD Operation 2
Neighbor Relationships 2
BFD Detection of Failures 3
BFD Version Interoperability 3
BFD Session Limits 4
BFD Support for Nonbroadcast Media Interfaces 4
BFD Support for Nonstop Forwarding with Stateful Switchover 4
BFD Support for Stateful Switchover 4
BFD Support for Static Routing 4
Benefits of Using BFD for Failure Detection 5
How to Configure Bidirectional Forwarding Detection 6
Configuring BFD Session Parameters on the Interface 6
Configuring BFD Support for Dynamic Routing Protocols 7
Configuring BFD Support for eBGP 7
Configuring BFD Support for EIGRP 8
Configuring BFD Support for IS-IS 10
Prerequisites 10
Configuring BFD Support for IS-IS for All Interfaces 11
Configuring BFD Support for IS-IS for One or More Interfaces 12
Configuring BFD Support for OSPF 13
Configuring BFD Support for OSPF for All Interfaces 14
Configuring BFD Support for OSPF for One or More Interfaces 15
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Configuring BFD Support for HSRP 17
Configuring BFD Support for Static Routing 18
Configuring BFD Echo Mode 21
Prerequisites 21
Restrictions 21
Disabling BFD Echo Mode Without Asymmetry 21
Creating and Configuring BFD Templates 22
Configuring a Single-Hop Template 22
Monitoring and Troubleshooting BFD 23
Monitoring and Troubleshooting BFD 23
Feature Information for Bidirectional Forwarding Detection 24
CHAPTER 2 Configuring MSDP 25
Information About Configuring MSDP 25
MSDP Overview 25
MSDP Operation 26
MSDP Benefits 27
How to Configure MSDP 28
Default MSDP Configuration 28
Configuring a Default MSDP Peer 28
Caching Source-Active State 30
Requesting Source Information from an MSDP Peer 31
Controlling Source Information that Your Switch Originates 32
Redistributing Sources 33
Filtering Source-Active Request Messages 35
Controlling Source Information that Your Switch Forwards 36
Using a Filter 36
Using TTL to Limit the Multicast Data Sent in SA Messages 39
Controlling Source Information that Your Switch Receives 40
Configuring an MSDP Mesh Group 42
Shutting Down an MSDP Peer 43
Including a Bordering PIM Dense-Mode Region in MSDP 44
Configuring an Originating Address other than the RP Address 46
Monitoring and Maintaining MSDP 47
Configuration Examples for Configuring MSDP 48
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Configuring a Default MSDP Peer: Example 48
Caching Source-Active State: Example 49
Requesting Source Information from an MSDP Peer: Example 49
Controlling Source Information that Your Switch Originates: Example 49
Controlling Source Information that Your Switch Forwards: Example 49
Controlling Source Information that Your Switch Receives: Example 50
Feature Information for Multicast Source Discovery Protocol 50
CHAPTER 3 Configuring IP Unicast Routing 51
Information About Configuring IP Unicast Routing 52
Information About IP Routing 52
Types of Routing 53
Classless Routing 53
Address Resolution 55
Proxy ARP 55
ICMP Router Discovery Protocol 55
UDP Broadcast Packets and Protocols 56
Broadcast Packet Handling 56
IP Broadcast Flooding 57
How to Configure IP Routing 57
How to Configure IP Addressing 58
Default IP Addressing Configuration 59
Assigning IP Addresses to Network Interfaces 60
Using Subnet Zero 61
Disabling Classless Routing 62
Configuring Address Resolution Methods 63
Defining a Static ARP Cache 63
Setting ARP Encapsulation 65
Enabling Proxy ARP 66
Routing Assistance When IP Routing is Disabled 68
Proxy ARP 68
Default Gateway 68
ICMP Router Discovery Protocol (IRDP) 69
Configuring Broadcast Packet Handling 71
Enabling Directed Broadcast-to-Physical Broadcast Translation 71
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Forwarding UDP Broadcast Packets and Protocols 73
Establishing an IP Broadcast Address 75
Flooding IP Broadcasts 76
Monitoring and Maintaining IP Addressing 77
How to Configure IP Unicast Routing 78
Enabling IP Unicast Routing 78
Example of Enabling IP Routing 79
What to Do Next 79
Information About RIP 80
Summary Addresses and Split Horizon 80
How to Configure RIP 81
Default RIP Configuration 81
Configuring Basic RIP Parameters 82
Configuring RIP Authentication 84
Configuring Summary Addresses and Split Horizon 85
Configuring Split Horizon 87
Configuration Example for Summary Addresses and Split Horizon 88
Information About OSPF 89
OSPF Nonstop Forwarding 89
OSPF NSF Awareness 90
OSPF NSF Capability 90
OSPF Area Parameters 90
Other OSPF Parameters 90
LSA Group Pacing 91
Loopback Interfaces 91
How to Configure OSPF 92
Default OSPF Configuration 92
Configuring Basic OSPF Parameters 93
Configuring OSPF Interfaces 95
Configuring OSPF Area Parameters 97
Configuring Other OSPF Parameters 99
Changing LSA Group Pacing 101
Configuring a Loopback Interface 102
Monitoring OSPF 103
Configuration Examples for OSPF 104
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Example: Configuring Basic OSPF Parameters 104
Information About EIGRP 104
EIGRP Features 104
EIGRP Components 105
EIGRP Nonstop Forwarding 106
EIGRP NSF Awareness 106
EIGRP NSF Capability 106
EIGRP Stub Routing 106
How to Configure EIGRP 107
Default EIGRP Configuration 108
Configuring Basic EIGRP Parameters 109
Configuring EIGRP Interfaces 111
Configuring EIGRP Route Authentication 113
Monitoring and Maintaining EIGRP 115
Information About BGP 115
BGP Network Topology 115
Nonstop Forwarding Awareness 117
Information About BGP Routing 117
Routing Policy Changes 117
BGP Decision Attributes 118
Route Maps 119
BGP Filtering 119
Prefix List for BGP Filtering 120
BGP Community Filtering 120
BGP Neighbors and Peer Groups 121
Aggregate Routes 121
Routing Domain Confederations 121
BGP Route Reflectors 121
Route Dampening 122
More BGP Information 122
How to Configure BGP 122
Default BGP Configuration 122
Enabling BGP Routing 126
Managing Routing Policy Changes 128
Configuring BGP Decision Attributes 129
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Configuring BGP Filtering with Route Maps 131
Configuring BGP Filtering by Neighbor 132
Configuring BGP Filtering by Access Lists and Neighbors 133
Configuring Prefix Lists for BGP Filtering 135
Configuring BGP Community Filtering 136
Configuring BGP Neighbors and Peer Groups 137
Configuring Aggregate Addresses in a Routing Table 140
Configuring Routing Domain Confederations 141
Configuring BGP Route Reflectors 143
Configuring Route Dampening 144
Monitoring and Maintaining BGP 145
IS-IS Routing 147
IS-IS Dynamic Routing 147
Nonstop Forwarding Awareness 147
IS-IS Global Parameters 148
IS-IS Interface Parameters 148
How to Configure IS-IS Routing 149
Default IS-IS Configuration 149
Enabling IS-IS Routing 150
Configuring IS-IS Global Parameters 152
Configuring IS-IS Interface Parameters 155
Monitoring and Maintaining IS-IS 158
Information About Multi-VRF CE 158
Understanding Multi-VRF CE 159
Network Topology 159
Packet-Forwarding Process 160
Network Components 161
VRF-Aware Services 161
How to Configure Multi-VRF CE 161
Default Multi-VRF CE Configuration 161
Multi-VRF CE Configuration Guidelines 162
Configuring VRFs 163
Configuring VRF-Aware Services 164
Configuring VRF-Aware Services for ARP 165
Configuring VRF-Aware Services for Ping 165
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Configuring VRF-Aware Services for SNMP 165
Configuring VRF-Aware Servcies for uRPF 166
Configuring VRF-Aware RADIUS 168
Configuring VRF-Aware Services for Syslog 168
Configuring VRF-Aware Services for Traceroute 169
Configuring VRF-Aware Services for FTP and TFTP 169
Configuring Multicast VRFs 170
Configuring a VPN Routing Session 173
Configuring BGP PE to CE Routing Sessions 174
Monitoring Multi-VRF CE 175
Configuration Examples for Multi-VRF CE 176
Multi-VRF CE Configuration Example 176
Configuring Unicast Reverse Path Forwarding 179
Protocol-Independent Features 179
Distributed Cisco Express Forwarding 180
Information About Cisco Express Forwarding 180
How to Configure Cisco Express Forwarding 180
Number of Equal-Cost Routing Paths 182
Information About Equal-Cost Routing Paths 182
How to Configure Equal-Cost Routing Paths 183
Static Unicast Routes 183
Information About Static Unicast Routes 183
Configuring Static Unicast Routes 184
Default Routes and Networks 186
Information About Default Routes and Networks 186
How to Configure Default Routes and Networks 186
Route Maps to Redistribute Routing Information 187
Information About Route Maps 187
How to Configure a Route Map 187
How to Control Route Distribution 191
Policy-Based Routing 193
Information About Policy-Based Routing 193
How to Configure PBR 194
Filtering Routing Information 197
Setting Passive Interfaces 197
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Controlling Advertising and Processing in Routing Updates 199
Filtering Sources of Routing Information 200
Managing Authentication Keys 201
Prerequisites 201
How to Configure Authentication Keys 201
Monitoring and Maintaining the IP Network 203
Feature Information for IP Unicast Routing 203
CHAPTER 4 Configuring Generic Routing Encapsulation(GRE) Tunnel IP Source and Destination VRF
Membership 205
Restrictions for GRE Tunnel IP Source and Destination VRF Membership 205
Information About GRE Tunnel IP Source and Destination VRF Membership 206
How to Configure GRE Tunnel IP Source and Destination VRF Membership 206
Configuration Example for GRE Tunnel IP Source and Destination VRF Membership 207
Additional References 208
Feature History for Generic Routing Encapsulation Tunnel IP Source and Destination VRF
Membership 209
Notices 211
Trademarks 211
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