Cisco Nexus 7000 Series Switches Configuration Guide

Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide

First Published: 2016-12-23

Last Modified: 2021-02-22

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CONTENTS

Preface xxix

PREFACE

Audience xxix

Document Conventions xxix

Related Documentation for Cisco Nexus 7000 Series NX-OS Software xxx

Documentation Feedback xxxii

Communications, Services, and Additional Information xxxiii

New and Changed Information 1

CHAPTER 1

New and Changed Information 1

Overview 3

CHAPTER 2

Overview 3

Licensing Requirements 3

Information About Layer 3 Unicast Routing 3

Routing Fundamentals 3

Packet Switching 4

Routing Metrics 5

Router IDs 6

Autonomous Systems 7

Convergence 8

Load Balancing and Equal Cost Multipath 8

Route Redistribution 8

Administrative Distance 9

Stub Routing 9

Routing Algorithms 10

Static Routes and Dynamic Routing Protocols 10

Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide

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Interior and Exterior Gateway Protocols 10

Distance Vector Protocols 10

Link-State Protocols 11

Layer 3 Virtualization 11

Cisco NX-OS Forwarding Architecture 12

Unicast RIB 12

Adjacency Manager 13

Unicast Forwarding Distribution Module 13

FIB 13

Hardware Forwarding 13

Software Forwarding 14

Layer 3 Interoperation with the N7K-F132-15 Module 14

Summary of Layer 3 Routing Features 15

IPv4 and IPv6 15

IP Services 15

OSPF 15

EIGRP 15

IS-IS 15

BGP 15

RIP 16

Static Routing 16

Layer 3 Virtualization 16

Route Policy Manager 16

Policy-Based Routing 16

First Hop Redundancy Protocols 16

Object Tracking 17

Related Documents for Layer 3 Unicast Routing 17

IP 19

PART I

Configuring IPv4 21

CHAPTER 3

Finding Feature Information 21

Information About IPv4 21

Multiple IPv4 Addresses 22

Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide

iv

Contents

Address Resolution Protocol 22

ARP Caching 23

Static and Dynamic Entries in the ARP Cache 23

Devices That Do Not Use ARP 23

Reverse ARP 24

Proxy ARP 24

Local Proxy ARP 25

Gratuitous ARP 25

Glean Throttling 25

Path MTU Discovery 25

ICMP 26

Virtualization Support for IPv4 26

IP Directed Broadcasts 26

Prerequisites for IPv4 28

Guidelines and Limitations for IPv4 28

Default Settings for IPv4 Parameters 28

Configuring IPv4 28

Configuring IPv4 Addressing 28

Configuring Multiple IPv4 Addresses 29

Configuring a Static ARP Entry 30

Configuring Proxy ARP 31

Configuring Local Proxy ARP 31

Configuring Gratuitous ARP 32

Configuring the IP ARP Cache Limit 33

Configuring Glean Optimization 33

Configuring Bloom Filter Support for Glean Adjacencies 34

Configuring Path MTU Discovery 35

Configuring IP Packet Verification 35

Enabling Forwarding of IP Directed Broadcasts 37

Disabling Forwarding of IP Directed Broadcasts 39

Configuring IP Glean Throttling 41

Configuring the Hardware IP Glean Throttle Maximum 42

Configuring the Hardware IP Glean Throttle Timeout 43

Configuring the Hardware IP Glean Throttle Syslog 43

Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide

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Contents

Verifying the IPv4 Configuration 44

Configuration Examples for IPv4 45

Example: Reserving All Ports on a Module for Proxy Routing 45

Example: Reserving Ports for Proxy Routing 47

Example: Excluding Ports From Proxy Routing 47

Cisco Nexus 7000 Series Switches Configuration Guide

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