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Cisco Nexus 3000 Series NX-OS Unicast

Routing Configuration Guide, Release

5.0(3)U2(2)

November 2011

OL-25782-02

Summary of content (368 pages)

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Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.0(3)U2(2) November 2011 Americas Headquarters Cisco Systems, Inc. 170 West Tasman Drive San Jose, CA 95134-1706 USA http://www.cisco.
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Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . THE SPECIFICATIONS AND INFORMATION REGARDING THE PRODUCTS IN THIS MANUAL ARE SUBJECT TO CHANGE WITHOUT NOTICE. ALL STATEMENTS, INFORMATION, AND RECOMMENDATIONS IN THIS MANUAL ARE BELIEVED TO BE ACCURATE BUT ARE PRESENTED WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED. USERS MUST TAKE FULL RESPONSIBILITY FOR THEIR APPLICATION OF ANY PRODUCTS.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Contents Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Contents S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Contents Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Contents S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Contents Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Contents S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Contents Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Contents S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Contents Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Contents S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Contents Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Contents S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Contents Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Contents S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Contents Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . First-Hop Redundancy Protocols RFCs IP Services RFCs A-2 OSPF RFCs A-2 RIP RFCs A-2 A-2 GLOSSARY INDEX Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . New and Changed Information This chapter provides release-specific information for each new and changed feature in the Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.0(3)U2(2). The latest version of this document is available at the following Cisco website: http://www.cisco.com/en/US/products/ps11541/products_installation_and_configuration_guides_list.
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New and Changed Information Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Preface This document describes the configuration details for Cisco NX-OS unicast routing in Cisco NX-OS switches.
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Preface Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Table 1 Supported Cisco Nexus 3000 Platform Switches Switch Description Cisco Nexus 3064PQ Switch The Cisco Nexus 3064UP switch is a high-performance, high-density, ultra-low-latency Ethernet switch that is part of the new Cisco Nexus 3000 Series Switches. This compact one-rack-unit (1RU) form factor 1 and 10 Gigabit Ethernet switch provides line-rate Layer 2 and 3 switching.
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Preface S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Title Description Chapter 13, “Configuring Route Policy Manager” Describes how to configure the Route Policy Manager, including IP prefix lists and route maps for filtering and redistribution. Chapter 14, “Configuring HSRP” Describes how to configure the Hot Standby Routing Protocol. Chapter 15, “Configuring VRRP” Describes how to configure the Virtual Router Redundancy Protocol.
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Preface Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Caution Means reader be careful. In this situation, you might do something that could result in equipment damage or loss of data. Related Documentation Documentation for the Cisco Nexus 3000 Series Switch is available at the following URL: http://www.cisco.com/en/US/products/ps11541/tsd_products_support_series_home.
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Preface S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Subscribe to the What’s New in Cisco Product Documentation as an RSS feed and set content to be delivered directly to your desktop using a reader application. The RSS feeds are a free service. Cisco currently supports RSS Version 2.0. Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.
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Preface Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . CH A P T E R 1 Overview This chapter introduces the underlying concepts for Layer 3 unicast routing protocols in Cisco NX-OS.
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Chapter 1 Overview Information About Layer 3 Unicast Routing Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Routing Fundamentals Routing protocols use a metric to evaluate the best path to the destination. A metric is a standard of measurement, such as a path bandwidth, that routing algorithms use to determine the optimal path to a destination.
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Chapter 1 Overview Information About Layer 3 Unicast Routing S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 1 Overview Information About Layer 3 Unicast Routing Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . • Communication Cost, page 1-4 Path Length The path length is the most common routing metric. Some routing protocols allow you to assign arbitrary costs to each network link. In this case, the path length is the sum of the costs associated with each link traversed.
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Chapter 1 Overview Information About Layer 3 Unicast Routing S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Router IDs Each routing process has an associated router ID. You can configure the router ID to any interface in the system. If you do not configure the router ID, Cisco NX-OS selects the router ID based on the following criteria: • Cisco NX-OS prefers loopback0 over any other interface.
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Chapter 1 Overview Information About Layer 3 Unicast Routing Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Note The autonomous system number assignment for public and private networks is governed by the Internet Assigned Number Authority (IANA). For information about autonomous system numbers, including the reserved number assignment, or to apply to register an autonomous system number, refer to the following URL: http://www.iana.
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Chapter 1 Overview Information About Layer 3 Unicast Routing S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Administrative Distance An administrative distance is a rating of the trustworthiness of a routing information source. The higher the value, the lower the trust rating. Typically, a route can be learned through more than one protocol. Administrative distance is used to discriminate between routes learned from more than one protocol.
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Chapter 1 Overview Routing Algorithms Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . OSPF supports stub areas and EIGRP supports stub routers. Routing Algorithms Routing algorithms determine how a router gathers and reports reachability information, how it deals with topology changes, and how it determines the optimal route to a destination.
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Chapter 1 Overview Routing Algorithms S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Distance Vector Protocols Distance vector protocols use distance vector algorithms (also known as Bellman-Ford algorithms) that call for each router to send all or some portion of its routing table to its neighbors.
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Chapter 1 Overview Layer 3 Virtualization Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . OSPF is an example of a link-state protocol. Layer 3 Virtualization Cisco NX-OS supports multiple Virtual Routing and Forwarding Instances (VRFs) and multiple routing information bases (RIBs) to support multiple address domains. Each VRF is associated with a routing information base (RIB) and this information is collected by the Forwarding Information Base (FIB).
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Chapter 1 Overview Cisco NX-OS Fowarding Architecture S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . The unicast RIB maintains the routing table with directly connected routes, static routes, and routes learned from dynamic unicast routing protocols. The unicast RIB also collects adjacency information from sources such as the Address Resolution Protocol (ARP).
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Chapter 1 Overview Summary of Layer 3 Unicast Routing Features Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . • RPF Loose Check—Packets have a verifiable source address in the routers forwarding table and the source is reachable through a physical interface. The ingress interface that receives the packet need not match any of the interfaces in the FIB. Hardware Forwarding Cisco NX-OS supports distributed packet forwarding.
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Chapter 1 Overview Summary of Layer 3 Unicast Routing Features S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . OSPF The OSPF protocol is a link-state routing protocol used to exchange network reachability information within an autonomous system. Each OSPF router advertises information about its active links to its neighbor routers. Link information consists of the link type, the link metric, and the neighbor router connected to the link.
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Chapter 1 Overview Related Topics Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Route Policy Manager The Route Policy Manager provides a route filtering capability in Cisco NX-OS. It uses route maps to filter routes distributed across various routing protocols and between different entities within a given routing protocol. Filtering is based on specific match criteria, which is similar to packet filtering by access control lists.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . CH A P T E R 2 Configuring IPv4 This chapter describes how to configure Internet Protocol version 4 (IPv4), which includes addressing, Address Resolution Protocol (ARP), and Internet Control Message Protocol (ICMP), on the Cisco NX-OS switch.
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Chapter 2 Configuring IPv4 Information About IPv4 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . The IP feature in the Cisco NX-OS system is responsible for handling IPv4 packets, as well as forwarding of IPv4 packets, which includes IPv4 unicast/multicast route lookup, reverse path forwarding (RPF) checks, and software access control list (ACL) forwarding.
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Chapter 2 Configuring IPv4 Information About IPv4 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Each switch compares the IP address to its own. Only the switch with the matching IP address replies to the switch that sends the data with a packet that contains the MAC address for the switch.
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Chapter 2 Configuring IPv4 Information About IPv4 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Devices that Do Not Use ARP When a network is divided into two segments, a bridge joins the segments and filters traffic to each segment based on MAC addresses. The bridge builds its own address table, which uses MAC addresses only, as opposed to a switch, which has an ARP cache that contains both IP addresses and the corresponding MAC addresses.
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Chapter 2 Configuring IPv4 Information About IPv4 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Proxy ARP Proxy ARP enables a switch that is physically located on one network appear to be logically part of a different physical network connected to the same switch or firewall.
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Chapter 2 Configuring IPv4 Licensing Requirements for IPv4 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . ICMP You can use ICMP to provide message packets that report errors and other information that is relevant to IP processing. ICMP generates error messages, such as ICMP destination unreachable messages, ICMP Echo Requests (which send a packet on a round trip between two hosts) and Echo Reply messages.
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Chapter 2 Configuring IPv4 Default Settings S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . • If the Cisco Nexus 3000 switch is used as a Layer 2 or Layer 3 termination switch, Cisco recommends that you set the mac-address-table-aging-time to 1800 (higher than the default ARP aging time of 1500 seconds) on all VLANs. • The Cisco Nexus 3000 switch does not support per-VLAN cam aging timers.
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Chapter 2 Configuring IPv4 Configuring IPv4 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . 4. ip address ip-address/length [secondary] 5. (Optional) show ip interface 6. (Optional) copy running-config startup-config DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 interface ethernet number Enters interface configuration mode.
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Chapter 2 Configuring IPv4 Configuring IPv4 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring Multiple IP Addresses You can only add secondary IP addresses after you configure primary IP addresses. SUMMARY STEPS 1. configure terminal 2. interface ethernet number 3. no switchport 4. ip address ip-address/length [secondary] 5. (Optional) show ip interface 6.
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Chapter 2 Configuring IPv4 Configuring IPv4 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . SUMMARY STEPS 1. configure terminal 2. interface ethernet number 3. no switchport 4. ip arp ipaddr mac_addr 5. (Optional) copy running-config startup-config DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode.
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Chapter 2 Configuring IPv4 Configuring IPv4 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . SUMMARY STEPS 1. configure terminal 2. interface ethernet number 3. no switchport 4. ip proxy-arp 5. (Optional) copy running-config startup-config DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode.
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Chapter 2 Configuring IPv4 Configuring IPv4 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . 3. no switchport 4. ip local-proxy-arp 5. (Optional) copy running-config startup-config DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 interface ethernet number Enters interface configuration mode.
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Chapter 2 Configuring IPv4 Configuring IPv4 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 interface ethernet number Enters interface configuration mode. Example: switch(config)# interface ethernet 2/3 switch(config-if)# Step 3 Configures the interface as a Layer 3 routed interface.
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Chapter 2 Configuring IPv4 Configuring IPv4 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . To enable IP directed broadcasts, use the following command in interface configuration mode: Command Purpose ip directed-broadcast Enables the translation of a directed broadcast to physical broadcasts Configuring IP Glean Throttling Cisco NX-OS software supports glean throttling rate limiters to protect the supervisor from the glean traffic.
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Chapter 2 Configuring IPv4 Configuring IPv4 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 3 Command Purpose no hardware ip glean throttle Disables ARP throttling. Example: switch(config)# no hardware ip glean throttle Step 4 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 2 Configuring IPv4 Configuring IPv4 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 3 Command Purpose no hardware ip glean throttle maximum count Applies the default limits. Example: switch(config)# no hardware ip glean throttle maximum 2134 Step 4 copy running-config startup-config The default value is 1000. The range is from 0 to 16,383 entries. (Optional) Saves this configuration change.
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Chapter 2 Configuring IPv4 Configuring IPv4 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 3 Command Purpose no hardware ip glean throttle maximum timeout timeout-in-sec Applies the default limits. Example: switch(config)# no hardware ip glean throttle maximum timeout 300 Step 4 copy running-config startup-config The timeout value is in seconds. The range is from 300 seconds (5 minutes) to 1800 seconds (30 minutes).
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Chapter 2 Configuring IPv4 Verifying the IPv4 Configuration Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 3 Command Purpose no hardware ip glean throttle syslog pck-count Applies the default limits. Example: switch(config)# no hardware ip glean throttle syslog 1030 Step 4 copy running-config startup-config The default is 10000 packets. The range is from 0 to 65535 packets.
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Chapter 2 Configuring IPv4 Additional References S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 2 Configuring IPv4 Feature History for IP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.
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Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . CH A P T E R 3 Configuring OSPFv2 This chapter describes how to configure Open Shortest Path First version 2 (OSPFv2) for IPv4 networks.
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Chapter 3 Configuring OSPFv2 Information About OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . OSPFv2 supports IPv4.
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Chapter 3 Configuring OSPFv2 Information About OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . If there is a match, the following information is entered into the neighbor table: • Neighbor ID—The router ID of the neighbor. • Priority—Priority of the neighbor. The priority is used for designated router election (see the “Designated Routers” section on page 3-3).
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Chapter 3 Configuring OSPFv2 Information About OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . All other routers establish adjacency with the DR and the BDR and use the IPv4 multicast address 224.0.0.6 to send LSA updates to the DR and BDR. Figure 3-1 shows this adjacency relationship between all routers and the DR. DRs are based on a router interface. A router might be the DR for one network and not for another network on a different interface.
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Chapter 3 Configuring OSPFv2 Information About OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Figure 3-2 OSPFv2 Areas ABR1 Area 3 Area 0 ABR2 182983 Area 5 The ABR has a separate link-state database for each area to which it connects. The ABR sends Network Summary (type 3) LSAs (see the “Route Summarization” section on page 3-10) from one connected area to the backbone area.
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Chapter 3 Configuring OSPFv2 Information About OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Table 3-1 LSA Types Type Name Description 1 Router LSA LSA sent by every router. This LSA includes the state and the cost of all links and a list of all OSPFv2 neighbors on the link. Router LSAs trigger an SPF recalculation. Router LSAs are flooded to local OSPFv2 area. 2 Network LSA LSA sent by the DR.
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Chapter 3 Configuring OSPFv2 Information About OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Link-State Database Each router maintains a link-state database for the OSPFv2 network. This database contains all the collected LSAs, and includes information on all the routes through the network. OSPFv2 uses this information to calculate the bast path to each destination and populates the routing table with these best paths.
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Chapter 3 Configuring OSPFv2 Information About OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Simple Password Authentication Simple password authentication uses a simple clear-text password that is sent as part of the OSPFv2 message. The receiving OSPFv2 router must be configured with the same clear-text password to accept the OSPFv2 message as a valid route update.
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Chapter 3 Configuring OSPFv2 Information About OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Figure 3-3 Stub Area ABR Backbone Area 10 ASBR 182984 Stub area Stub areas use a default route for all traffic that needs to go through the backbone area to the external autonomous system. The default route is 0.0.0.0 for IPv4.
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Chapter 3 Configuring OSPFv2 Information About OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Figure 3-4 Virtual Links Area 0 ABR2 ABR1 Area 3 182985 Area 5 You can also use virtual links to temporarily recover from a partitioned area, which occurs when a link within the area fails, isolating part of the area from reaching the designated ABR to the backbone area.
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Chapter 3 Configuring OSPFv2 Licensing Requirements for OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . External route summarization is specific to external routes that are injected into OSPFv2 using route redistribution. You should make sure that external ranges that are being summarized are contiguous. Summarizing overlapping ranges from two different routers could cause packets to be sent to the wrong destination.
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Chapter 3 Configuring OSPFv2 Prerequisites for OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Product License Requirement Cisco NX-OS OSPFv2 requires a LAN Base Services license. For over 256 routes, OSPFv2 requires an Enterprise services license. For a complete explanation of the Cisco NX-OS licensing scheme and how to obtain and apply licenses, see the Cisco NX-OS Licensing Guide.
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Chapter 3 Configuring OSPFv2 Configuring Basic OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Table 3-2 Default OSPFv2 Parameters (continued) Parameters Default LSA group pacing 240 seconds SPF calculation initial delay time 0 milliseconds SPF calculation hold time 5000 milliseconds SPF calculation initial delay time 0 milliseconds Configuring Basic OSPFv2 Configure OSPFv2 after you have designed your OSPFv2 network.
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Chapter 3 Configuring OSPFv2 Configuring Basic OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 3 Command Purpose show feature (Optional) Displays enabled and disabled features. Example: switch(config)# show feature Step 4 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 3 Configuring OSPFv2 Configuring Basic OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 router ospf instance-tag Example: switch(config)# router ospf 201 switch(config-router)# Step 3 router-id ip-address Example: switch(config-router)# router-id 192.0.2.
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Chapter 3 Configuring OSPFv2 Configuring Basic OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . OSPFv2 must be able to obtain a router identifier (for example, a configured loopback address) or you must configure the router ID option. DETAILED STEPS You can configure the following optional parameters for OSPFv2 in router configuration mode: Command Purpose distance number Configures the administrative distance for this OSPFv2 instance.
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Chapter 3 Configuring OSPFv2 Configuring Basic OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . 3. no switchport 4. ip address ip-prefix/length 5. ip router ospf instance-tag area area-id [secondaries none] 6. (Optional) show ip ospf instance-tag interface interface-type slot/port 7. (Optional) copy running-config startup-config DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode.
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Chapter 3 Configuring OSPFv2 Configuring Basic OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . You can configure the following optional parameters for OSPFv2 in interface configuration mode: Command Purpose ip ospf cost number Configures the OSPFv2 cost metric for this interface. The default is to calculate cost metric, based on reference bandwidth and interface bandwidth. The range is from 1 to 65535.
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Chapter 3 Configuring OSPFv2 Configuring Basic OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . BEFORE YOU BEGIN Ensure that you have enabled the OSPF feature (see the “Enabling the OSPFv2 Feature” section on page 3-13). Ensure that all neighbors on an interface share the same authentication configuration, including the shared authentication key. Create the key-chain for this authentication configuration.
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Chapter 3 Configuring OSPFv2 Configuring Basic OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 5 Command Purpose no switchport Configures the interface as a Layer 3 routed interface.
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Chapter 3 Configuring OSPFv2 Configuring Basic OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . 6. (Optional) ip ospf authentication-key [0 | 3] key 7. (Optional) ip ospf message-digest-key key-id md5 [0 | 3] key 8. (Optional) show ip ospf instance-tag interface interface-type slot/port 9. (Optional) copy running-config startup-config DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode.
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 8 Command Purpose show ip ospf instance-tag interface interface-type slot/port (Optional) Displays OSPF information. Example: switch(config-if)# show ip ospf 201 interface ethernet 1/2 Step 9 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring Filter Lists for Border Routers You can separate your OSPFv2 domain into a series of areas that contain related networks. All areas must connect to the backbone area through an area border router (ABR). OSPFv2 domains can connect to external domains as well, through an autonomous system border router (ASBR).
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 4 Command Purpose show ip ospf policy statistics area id filter-list {in | out} (Optional) Displays OSPF policy information. Example: switch(config-if)# show ip ospf policy statistics area 0.0.0.10 filter-list in Step 5 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 router ospf instance-tag Example: switch(config)# router ospf 201 switch(config-router)# Step 3 Creates a new OSPFv2 instance with the configured instance tag. Creates this area as a stub area.
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose area area-id stub no-summary Creates this area as a totally stubby area. Example: switch(config-router)# area 20 stub no-summary Configuring NSSA You can configure an NSSA for part of an OSPFv2 domain where limited external traffic is required. See the “Not-So-Stubby Area” section on page 3-9.
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode.
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . This example shows how to create an NSSA that always translates NSSA External (type 5) LSAs to AS External (type 7) LSAs: switch# configure terminal switch(config)# router ospf 201 switch(config-router)# area 0.0.0.
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 Creates a new OSPFv2 instance with the configured instance tag.
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command or Action Purpose message-digest-key key-id md5 [0 | 3] key (Optional) Configures message digest authentication for this virtual link. Use this command if the authentication is set to message-digest. 0 configures the password in cleartext. 3 configures the pass key as 3DES encrypted.
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Create the necessary route maps used for redistribution. SUMMARY STEPS 1. configure terminal 2. router ospf instance-tag 3. redistribute {bgp id | direct | eigrp id | ospf id | rip id | static} route-map map-name 4. default-information originate [always] [route-map map-name] 5. default-metric cost 6.
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode.
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring Route Summarization You can configure route summarization for inter-area routes by configuring an address range that is summarized. You can also configure route summarization for external, redistributed routes by configuring a summary address for those routes on an ASBR. See the “Route Summarization” section on page 3-10.
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 5 Command Purpose show ip ospf summary-address (Optional) Displays information about OSPF summary addresses. Example: switch(config-router)# show ip ospf summary-address Step 6 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 router ospf instance-tag Example: switch(config)# router ospf 201 switch(config-router)# Creates a new OSPFv2 instance with the configured instance tag.
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . See the “Configuring Networks in OSPFv2” section on page 3-16 for information about the hello interval and dead timer. BEFORE YOU BEGIN Ensure that you have enabled the OSPF feature (see the “Enabling the OSPFv2 Feature” section on page 3-13). SUMMARY STEPS 1. configure terminal 2. router ospf instance-tag 3. timers lsa-arrival msec 4.
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 4 Command Purpose timers lsa-group-pacing seconds Sets the interval in seconds for grouping LSAs. The range is from 1 to 1800. The default is 240 seconds.
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 13 Command Purpose show ip ospf (Optional) Displays information about OSPF. Example: switch(config-if)# show ip ospf Step 14 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 3 Configuring OSPFv2 Configuring Advanced OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . 4. vrf vrf-name 5. maximum-paths paths 6. interface interface-type slot/port 7. no switchport 8. vrf member vrf-name 9. ip-address ip-prefix/length 10. ip router ospf instance-tag area area-id 11. (Optional) copy running-config startup-config DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode.
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Chapter 3 Configuring OSPFv2 Verifying the OSPFv2 Configuration S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 8 Command Purpose vrf member vrf-name Adds this interface to a VRF. Example: switch(config-if)# vrf member RemoteOfficeVRF Step 9 Configures an IP address for this interface. You must do this step after you assign this interface to a VRF. ip address ip-prefix/length Example: switch(config-if)# ip address 192.0.2.
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Chapter 3 Configuring OSPFv2 Displaying OSPFv2 Statistics Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose show ip ospf neighbors [neighbor-id] [detail] [interface-type number] [vrf {vrf-name | all | default | management}] [summary] Displays the list of OSPFv2 neighbors. show ip ospf request-list neighbor-id [interface-type number] Displays the list of OSPFv2 link-state requests.
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Chapter 3 Configuring OSPFv2 Additional References S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . interface ethernet 1/2 no switchport ip router ospf 201 area 0.0.0.
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Chapter 3 Configuring OSPFv2 Feature History for OSPFv2 Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . CH A P T E R 4 Configuring EIGRP This chapter describes how to configure the Enhanced Interior Gateway Routing Protocol (EIGRP) on the Cisco NX-OS switch.
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Chapter 4 Configuring EIGRP Information About EIGRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . • Advanced EIGRP, page 4-4 EIGRP Components EIGRP has the following basic components: • Reliable Transport Protocol, page 4-2 • Neighbor Discovery and Recovery, page 4-2 • Diffusing Update Algorithm, page 4-3 Reliable Transport Protocol The Reliable Transport Protocol guarantees ordered delivery of EIGRP packets to all neighbors.
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Chapter 4 Configuring EIGRP Information About EIGRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Diffusing Update Algorithm The Diffusing Update Algorithm (DUAL) calculates the routing information based on the destination networks in the topology table. The topology table includes the following information: • IPv4 address/mask—The network address and network mask for this destination.
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Chapter 4 Configuring EIGRP Information About EIGRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . We recommend that you use the default bandwidth value. This bandwidth parameter is also used by EIGRP. Note • MTU—The smallest maximum transmission unit value along the route to the destination. • Hop count—The number of hops or routers that the route passes through to the destination. This metric is not directly used in the DUAL computation.
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Chapter 4 Configuring EIGRP Information About EIGRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Address Families EIGRP supports the IPv4 address family.
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Chapter 4 Configuring EIGRP Information About EIGRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . When using EIGRP stub routing, you need to configure the distribution and remote routers to use EIGRP and configure only the remote router as a stub. EIGRP stub routing does not automatically enable summarization on the distribution router. In most cases, you need to configure summarization on the distribution routers.
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Chapter 4 Configuring EIGRP Licensing Requirements for EIGRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Split horizon is a method that controls the sending of EIGRP update and query packets. When you enable split horizon on an interface, Cisco NX-OS does not send update and query packets for destinations that were learned from this interface. Controlling update and query packets in this manner reduces the possibility of routing loops.
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Chapter 4 Configuring EIGRP Default Settings Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Note • For graceful restart, an NSF-aware router must be up and completely converged with the network before it can assist an NSF-capable router in a graceful restart operation. • For graceful restart, neighboring switches participating in the graceful restart must be NSF-aware or NSF-capable.
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Chapter 4 Configuring EIGRP Configuring Basic EIGRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 4 Configuring EIGRP Configuring Basic EIGRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 3 Command Purpose show feature (Optional) Displays information about enabled features. Example: switch(config)# show feature Step 4 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 4 Configuring EIGRP Configuring Basic EIGRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . 10. (Optional) copy running-config startup-config DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode.
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Chapter 4 Configuring EIGRP Configuring Basic EIGRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 9 Command Purpose show ip eigrp interfaces Displays information about EIGRP interfaces. Example: switch(config-if)# show ip eigrp interfaces Step 10 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 4 Configuring EIGRP Configuring Advanced EIGRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Shutting Down an EIGRP Instance You can gracefully shut down an EIGRP instance. This action moves all routes and adjacencies but preserves the EIGRP configuration. To disable an EIGRP instance, use the following command in router configuration mode: Command Purpose switch(config-router)# shutdown Disables this instance of EIGRP.
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Chapter 4 Configuring EIGRP Configuring Advanced EIGRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 4 Configuring EIGRP Configuring Advanced EIGRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 router eigrp instance-tag Example: switch(config)# router eigrp Test1 switch(config-router)# Creates a new EIGRP process with the configured instance tag.
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Chapter 4 Configuring EIGRP Configuring Advanced EIGRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 10 Command Purpose ip authentication mode eigrp instance-tag md5 Configures the MD5 message digest authentication mode for this interface. This configuration overrides the authentication configuration set in the router VRF mode.
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Chapter 4 Configuring EIGRP Configuring Advanced EIGRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . IP-EIGRP neighbors for process 201 H Address Interface 0 Hold Uptime SRTT (sec) (ms) 10.1.1.2 Se3/1 11 00:00:59 1 Version 12.1/1.
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Chapter 4 Configuring EIGRP Configuring Advanced EIGRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . 2. router eigrp instance-tag 3. address-family ipv4 unicast 4. redistribute {bgp as | {eigrp | ospf | ospfv3 | rip} instance-tag | direct | static} route-map name 5. default-metric bandwidth delay reliability loading mtu 6. show ip eigrp route-map statistics redistribute 7.
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Chapter 4 Configuring EIGRP Configuring Advanced EIGRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 6 Command Purpose show ip eigrp route-map statistics redistribute Displays information about EIGRP route map statistics. Example: switch(config-router-af)# show ip eigrp route-map statistics redistribute bgp Step 7 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 4 Configuring EIGRP Configuring Advanced EIGRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . 6. (Optional) copy running-config startup-config DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode.
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Chapter 4 Configuring EIGRP Configuring Advanced EIGRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring Load Balancing in EIGRP You can configure load balancing in EIGRP. You can configure the number of Equal Cost Multiple Path (ECMP) routes using the maximum paths option. See the “Configuring Load Balancing in EIGRP” section on page 4-21.
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Chapter 4 Configuring EIGRP Configuring Advanced EIGRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 4 Step 5 Command Purpose maximum-paths num-paths Example: switch(config-router-af)# maximum-paths 5 Sets the number of equal cost paths that EIGRP will accept in the route table. The range is from 1 to 16. The default is 8. copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 4 Configuring EIGRP Configuring Advanced EIGRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Disabling Split Horizon You can use split horizon to block route information from being advertised by a router out of any interface from which that information originated. Split horizon usually optimizes communications among multiple routing switches, particularly when links are broken. By default, split horizon is enabled on all interfaces.
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Chapter 4 Configuring EIGRP Configuring Advanced EIGRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose metric weights tos k1 k2 k3 k4 k5 Adjusts the EIGRP metric or K value.
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Chapter 4 Configuring EIGRP Configuring Virtualization for EIGRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose no ip next-hop-self eigrp instance-tag Configures EIGRP to use the received next-hop address rather than the address for this interface. The default is to use the IP address of this interface for the next-hop address. The instance tag can be any case-sensitive, alphanumeric string up to 20 characters.
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Chapter 4 Configuring EIGRP Configuring Virtualization for EIGRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode.
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Chapter 4 Configuring EIGRP Verifying the EIGRP Configuration S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 4 Configuring EIGRP Configuration Examples for EIGRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuration Examples for EIGRP This example shows how to configure EIGRP: feature eigrp interface ethernet 1/2 no switchport ip address 192.0.2.55/24 ip router eigrp Test1 no shutdown router eigrp Test1 router-id 192.0.2.1 Related Topics See Chapter 13, “Configuring Route Policy Manager” for more information on route maps.
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Chapter 4 Configuring EIGRP Feature History for EIGRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Related Documents Related Topic Document Title EIGRP CLI commands Cisco Nexus 3000 Series Command Reference, http://www.cisco.com/warp/public/103/1.html Introduction to EIGRP Tech Note http://www.cisco.com/en/US/tech/tk365/technologies _q_and_a_item09186a008012dac4.
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Chapter 4 Configuring EIGRP Feature History for EIGRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.
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Se n d d o c u m e n t c o m m e n t s t o n e x u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . CH A P T E R 5 Configuring Basic BGP This chapter describes how to configure Border Gateway Protocol (BGP) on a Cisco NX-OS switch.
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Chapter 5 Configuring Basic BGP Information About Basic BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . BGP selects a single path, by default, as the best path to a destination host or network. Each path carries well-known mandatory, well-known discretionary, and optional transitive attributes that are used in BGP best-path analysis. You can influence BGP path selection by altering some of these attributes by configuring BGP policies.
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Chapter 5 Configuring Basic BGP Information About Basic BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Note The administrative distance does not influence the BGP path selection algorithm, but it does influence whether BGP-learned routes are installed in the IP routing table. For more information, see the “Administrative Distance” section on page 1-7. BGP Peers A BGP speaker does not discover another BGP speaker automatically.
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Chapter 5 Configuring Basic BGP Information About Basic BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . BGP Router Identifier To establish BGP sessions between peers, BGP must have a router ID, which is sent to BGP peers in the OPEN message when a BGP session is established. The BGP router ID is a 32-bit value that is often represented by an IPv4 address. You can configure the router ID.
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Chapter 5 Configuring Basic BGP Information About Basic BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 1—Comparing Pairs of Paths This first step in the BGP best-path algorithm compares two paths to determine which path is better. The following sequence describes the basic steps that Cisco NX-OS uses to compare two paths to determine the better path: 1. Cisco NX-OS chooses a valid path for comparison.
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Chapter 5 Configuring Basic BGP Information About Basic BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . 8. If one path is from an internal peer and the other path is from an external peer, then Cisco NX-OS chooses the path from the external peer. 9. If the paths have different IGP metrics to their next-hop addresses, then Cisco NX-OS chooses the path with the lower IGP metric. 10.
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Chapter 5 Configuring Basic BGP Licensing Requirements for Basic BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . You can turn off the suppression feature by configuring the best-path algorithm to compare the router IDs. See the “Tuning the Best-Path Algorithm” section on page 6-9 for more information. If you configure this feature, the new best path is always preferred to the existing one.
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Chapter 5 Configuring Basic BGP Guidelines and Limitations for BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . • You must enable the BGP feature (see the “Enabling the BGP Feature” section on page 5-11). • You should have a valid router ID configured on the system. • You must have an AS number, either assigned by a Regional Internet Registry (RIR) or locally administered.
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Chapter 5 Configuring Basic BGP CLI Configuration Modes S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Global Configuration Mode Use global configuration mode to create a BGP process and configure advanced features such as AS confederation and route dampening. For more information, see Chapter 6, “Configuring Advanced BGP.
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Chapter 5 Configuring Basic BGP Default Settings Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . switch(config)# router bgp 64497 switch(config-router)# vrf vrf_A switch(config-router-vrf)# neighbor 192.0.2.
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Chapter 5 Configuring Basic BGP Configuring Basic BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Note • Configuring BGP Peers, page 5-14 • Configuring Dynamic AS Numbers for Prefix Peers, page 5-16 • Clearing BGP Information, page 5-18 If you are familiar with the Cisco IOS CLI, be aware that the Cisco NX-OS commands for this feature might differ from the Cisco IOS commands that you would use.
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Chapter 5 Configuring Basic BGP Configuring Basic BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Creating a BGP Instance You can create a BGP instance and assign a router ID to the BGP instance. See the “BGP Router Identifier” section on page 5-4. Cisco NX-OS supports 2-byte or 4-byte autonomous system (AS) numbers in plain-text notation or as.dot notation. See the “4-Byte AS Number Support” section on page 5-2 for more information.
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Chapter 5 Configuring Basic BGP Configuring Basic BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 5 Command Purpose network ip-prefix [route-map map-name] (Optional) Specifies a network as local to this autonomous system and adds it to the BGP routing table. Example: switch(config-router-af)# network 192.0.2.
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Chapter 5 Configuring Basic BGP Configuring Basic BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Shutting Down BGP You can shut down the BGP protocol and gracefully disable BGP and retain the configuration. To shut down BGP, use the following command in router configuration mode: Command Purpose shutdown Gracefully shuts down BGP.
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Chapter 5 Configuring Basic BGP Configuring Basic BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 router bgp autonomous-system-number Example: switch(config)# router bgp 64496 switch(config-router)# Step 3 neighbor ip-address remote-as as-number Example: switch(config-router)# neighbor 209.165.201.
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Chapter 5 Configuring Basic BGP Configuring Basic BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . This example shows how to configure a BGP peer: switch# configure terminal switch(config)# router bgp 64496 switch(config-router)# neighbor 192.0.2.
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Chapter 5 Configuring Basic BGP Configuring Basic BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 3 Command Purpose neighbor prefix remote-as route-map map-name Configures the IPv 4 prefix and a route map for the list of accepted AS numbers for the remote BGP peers. The prefix format for IPv4 is x.x.x.x/length. The length range is from 1 to 32. Example: switch(config-router)# neighbor 192.0.2.
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Chapter 5 Configuring Basic BGP Configuring Basic BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Clearing BGP Information To clear BGP information, use the following commands: Command Purpose clear bgp all {neighbor | * | as-number | peer-template name | prefix} [vrf vrf-name] Clears one or more neighbors from all address families. * clears all neighbors in all address families.
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Chapter 5 Configuring Basic BGP Configuring Basic BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose clear bgp ip {unicast | multicast} {neighbor | * Clears one or more neighbors from the selected | as-number | peer-template name | prefix} [vrf address family. * clears all neighbors in the vrf-name] address family. The arguments are as follows: • neighbor—IPv4 address of a neighbor. • as-number— Autonomous system number.
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Chapter 5 Configuring Basic BGP Configuring Basic BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose clear ip bgp flap-statistics [ip-neighbor | ip-prefix] [vrf vrf-name] Clears route flap statistics in one or more networks. The arguments are as follows: • ip-neighbor—IPv4 address of a neighbor. • ip-prefix—IPv4. All neighbors within that prefix are cleared. • vrf-name—VRF name. All neighbors in that VRF are cleared.
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Chapter 5 Configuring Basic BGP Verifying the Basic BGP Configuration S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose clear ip mbgp dampening [ip-neighbor | ip-prefix] [vrf vrf-name] Clears route flap dampening in one or more networks. The arguments are as follows: clear ip mbgp flap-statistics [ip-neighbor | ip-prefix] [vrf vrf-name] • ip-neighbor—IPv4 address of a neighbor. • ip-prefix—IPv4.
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Chapter 5 Configuring Basic BGP Verifying the Basic BGP Configuration Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose show bgp ip {unicast | multicast} [ip-address] {dampening dampened-paths [regexp expression]} [vrf vrf-name] Displays the information for BGP route dampening. Use the clear bgp dampening command to clear the route flap dampening information.
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Chapter 5 Configuring Basic BGP Displaying BGP Statistics S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Displaying BGP Statistics To display BGP statistics, use the following commands: Command Purpose show bgp ip {unicast | multicast} [ip-address] flap-statistics [vrf vrf-name] Displays the BGP route flap statistics. Use the clear bgp flap-statistics command to clear these statistics.
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Chapter 5 Configuring Basic BGP Feature History for BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Related Documents Related Topic Document Title BGP CLI commands Cisco Nexus 3000 Series Command Reference, MIBs MIBs MIBs Link BGP4-MIB To locate and download MIBs, go to the following URL: CISCO-BGP4-MIB http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . CH A P T E R 6 Configuring Advanced BGP This chapter describes how to configure advanced features of the Border Gateway Protocol (BGP) on the Cisco NX-OS switch.
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Chapter 6 Configuring Advanced BGP Information About Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 6 Configuring Advanced BGP Information About Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Route Policies and Resetting BGP Sessions You can associate a route policy to a BGP peer. Route policies use route maps to control or modify the routes that BGP recognizes. You can configure a route policy for inbound or outbound route updates.
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Chapter 6 Configuring Advanced BGP Information About Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Figure 6-1 iBGP Network AS10 Z A C eBGP iBGP iBGP iBGP iBGP B iBGP 185055 AS20 D iBGP networks are fully meshed. Each iBGP peer has a direct connection to all other iBGP peers to prevent network loops. Note You should configure a separate interior gateway protocol in the iBGP network.
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Chapter 6 Configuring Advanced BGP Information About Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . In this example, AS10 is split into two subautonomous systems, AS1 and AS2. Each subautonomous system is fully meshed, but there is only one link between the subautonomous systems. By using AS confederations, you can reduce the number of links compared to the fully meshed autonomous system in Figure 6-1.
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Chapter 6 Configuring Advanced BGP Information About Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Route Dampening Route dampening is a BGP feature that minimizes the propagation of flapping routes across an internetwork. A route flaps when it alternates between the available and unavailable states in rapid succession. For example, consider a network with three BGP autonomous systems: AS1, AS2, and AS3.
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Chapter 6 Configuring Advanced BGP Information About Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Route Aggregation You can configure aggregate addresses. Route aggregation simplifies route tables by replacing a number of more specific addresses with an address that represents all the specific addresses. For example, you can replace these three more specific addresses, 10.1.1.0/24, 10.1.2.0/24, and 10.1.3.
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Chapter 6 Configuring Advanced BGP Information About Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . • Note Next hop becomes a nonlocal address. Reachability and recursed metric events trigger a best-path recalculation. Event notifications from the RIB are classified as critical and noncritical. Notifications for critical and noncritical events are sent in separate batches.
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Chapter 6 Configuring Advanced BGP Licensing Requirements for Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . BGP Timers BGP uses different types of timers for neighbor session and global protocol events. Each established session has a minimum of two timers for sending periodic keepalive messages and for timing out sessions when peer keepalives do not arrive within the expected time.
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Chapter 6 Configuring Advanced BGP Prerequisites for BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Product License Requirement Cisco NX-OS BGP requires an LAN Enterprise Services license. For a complete explanation of the Cisco NX-OS licensing scheme and how to obtain and apply licenses, see the Cisco NX-OS Licensing Guide. Make sure the LAN Base Services license is installed on the switch to enable Layer 3 interfaces.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring BGP Session Templates You can use BGP session templates to simplify BGP configuration for multiple BGP peers with similar configuration needs. BGP templates allow you to reuse common configuration blocks. You configure BGP templates first, and then apply these templates to BGP peers.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 10 Command Purpose show bgp peer-session template-name (Optional) Displays the peer-policy template. Example: switch(config-router-neighbor)# show bgp peer-session BaseSession Step 11 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . 2. router bgp autonomous-system-number 3. template peer-policy template-name 4. advertise-active-only 5. maximum-prefix number 6. exit 7. neighbor ip-address remote-as as-number 8. address-family ipv4 {multicast | unicast} 9. inherit peer-policy template-name preference 10. (Optional) show bgp peer-policy template-name 11.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 8 Command Purpose address-family ipv4 {multicast | unicast} Enters global address family configuration mode for the IPv4 address family.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . BEFORE YOU BEGIN Ensure that you have enabled the BGP feature (see the “Enabling the BGP Feature” section on page 5-11). Note When editing a template, you can use the no form of a command at either the peer or template level to explicitly override a setting in a template.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 4 Command Purpose inherit peer-session template-name (Optional) Inherits a peer-session template in the peer template.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Use the show bgp neighbor command to see the template applied. See the Cisco Nexus 3000 Series Command Reference,, for details on all commands available in the template.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Modifying the Next-Hop Address You can modify the next-hop address used in a route advertisement in the following ways: • Disable the next-hop calculation and use the local BGP speaker address as the next-hop address. • Set the next-hop address as a third-party address.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring Next-Hop Filtering BGP next-hop filtering allows you to specify that when a next-hop address is checked with the RIB, the underlying route for that next-hop address is passed through the route map. If the route map rejects the route, the next-hop address is treated as unreachable.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . To disable checking whether or not a single-hop eBGP peer is directly connected, use the following command in neighbor configuration mode: Command Purpose disable-connected-check Disables checking whether or not a single-hop eBGP peer is directly connected. You must manually reset the BGP sessions after using this command.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Limiting the AS-path Attribute You can configure eBGP to discard routes that have a high number of AS numbers in the AS-path attribute.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring AS Confederations To configure an AS confederation, you must specify a confederation identifier. To the outside world, the group of autonomous systems within the AS confederation look like a single autonomous system with the confederation identifier as the autonomous system number.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . 7. neighbor ip-address remote-as as-number 8. address-family ipv4 {unicast | multicast} 9. route-reflector-client 10. show bgp ip {unicast | multicast} neighbors 11. (Optional) copy running-config startup-config DETAILED STEPS Step 1 Command or Action Purpose configure terminal Enters configuration mode.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 8 Command or Action Purpose address-family ipv4 {unicast | multicast} Enters neighbor address family configuration mode for the unicast IPv4 address family.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring Load Sharing and ECMP You can configure the maximum number of paths that BGP adds to the route table for equal-cost multipath load balancing.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring Aggregate Addresses You can configure aggregate address entries in the BGP route table.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . 3. neighbor ipaddress remote-as as-number 4. address-family ipv4 {unicast | multicast} 5. advertise-map adv-map {exist-map exist-rmap | non-exist-map nonexist-rmap} 6. (Optional) show ip bgp neighbor 7. (Optional) copy running-config startup-config DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 5 Command Purpose advertise-map adv-map {exist-map exist-rmap | non-exist-map nonexist-rmap} Configures BGP to conditionally advertise routes based on the two configured route maps: • adv-map—Specifies a route map with match statements that the route must pass before BGP passes the route to the next route map.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . BEFORE YOU BEGIN Ensure that you have enabled the BGP feature (see the “Enabling the BGP Feature” section on page 5-11). SUMMARY STEPS 1. configure terminal 2. router bgp as-number 3. address-family ipv4 {unicast | multicast} 4. redistribute {direct | {eigrp | ospf | ospfv3 | rip} instance-tag | static} route-map map-name 5.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 4 Command Purpose address-family ipv4 {unicast | multicast} Enters address family configuration mode. Example: switch(config-router-neighbor)# address-family ipv4 multicast switch(config-router-neighbor-af)# Step 5 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose bestpath [always-compare-med | compare-routerid | med {missing-as-worst | non-deterministic}| as-path multipath-relax] Modifies the best-path algorithm.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . To tune BGP, use the following optional command in router address-family configuration mode: Command Purpose distance ebgp-distance ibgp distance local-distance Sets the administrative distance for BGP. The range is from 1 to 255. The defaults are as follows: Example: switch(config-router-af)# distance 20 100 200 • eBGP distance—20.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose suppress-inactive Advertises the best (active) routes only to the BGP peer. This command triggers an automatic soft clear or refresh of BGP neighbor sessions. Example: switch(config-router-neighbor-af)# suppress-inactive default-originate [route-map map-name] Generates a default route to the BGP peer.
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Chapter 6 Configuring Advanced BGP Configuring Advanced BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . 8. (Optional) copy running-config startup-config DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode.
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Chapter 6 Configuring Advanced BGP Verifying the Advanced BGP Configuration S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . switch(config-router-vrf)# neighbor 209.165.201.
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Chapter 6 Configuring Advanced BGP Displaying BGP Statistics Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose show bgp ip {unicast | multicast} [ip-address] prefix-list list-name [vrf vrf-name] Displays the BGP routes that match the prefix list. show bgp ip {unicast | multicast} [ip-address] received-paths [vrf vrf-name] Displays the BGP paths stored for soft reconfiguration.
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Chapter 6 Configuring Advanced BGP Additional References S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 6 Configuring Advanced BGP Feature History for BGP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . CH A P T E R 7 Configuring Bidirectional Forwarding Detection for BGP This chapter describes how to configure Bidirectional Forwarding Detection (BFD) for BGP.
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Chapter 7 Configuring Bidirectional Forwarding Detection for BGP Information About BFD Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Asynchronous Mode Cisco NX-OS supports the BFD asynchronous mode, which sends BFD control packets between two adjacent devices to activate and maintain BFD neighbor sessions between the devices. You configure BFD on both devices (or BFD neighbors).
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Chapter 7 Configuring Bidirectional Forwarding Detection for BGP Licensing Requirements for BFD S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Security Cisco NX-OS uses the packet Time to Live (TTL) value to verify that the BFD packets came from an adjacent BFD peer. For all asynchronous and echo request packets, the BFD neighbor sets the TTL value to 255 and the local BFD process verifies the TTL value as 255 before processing the incoming packet.
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Chapter 7 Configuring Bidirectional Forwarding Detection for BGP Default Settings Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . • BFD depends on a Layer 3 adjacency information to discover topology changes, including Layer 2 topology changes. A BFD session on a VLAN interface (SVI) may not be up after the convergence of the Layer 2 topology if there is no Layer 3 adjacency information available.
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Chapter 7 Configuring Bidirectional Forwarding Detection for BGP Configuring BFD S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 7 Configuring Bidirectional Forwarding Detection for BGP Configuring BFD Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Enabling the BFD Feature You must enable the BFD feature before you can configure BFD on an interface and protocol within a device (VDC). BEFORE YOU BEGIN Ensure that you are in the correct VDC (or use the switchto vdc command). SUMMARY STEPS 1. configure terminal 2. feature bfd 3.
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Chapter 7 Configuring Bidirectional Forwarding Detection for BGP Configuring BFD S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . BEFORE YOU BEGIN Ensure that you are in the correct VDC (or use the switchto vdc command). Enable the BFD feature. See the “Enabling the BFD Feature” section on page 7-6. SUMMARY STEPS 1. configure terminal 2. bfd interval mintx min_rx msec multiplier value 3. bfd slow-timer [interval] 4.
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Chapter 7 Configuring Bidirectional Forwarding Detection for BGP Configuring BFD Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring BFD on an Interface You can configure the BFD session parameters for all BFD sessions on an interface. The BFD session parameters are negotiated between the BFD peers in a three-way handshake. This configuration overrides the global session parameters for the configured interface.
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Chapter 7 Configuring Bidirectional Forwarding Detection for BGP Configuring BFD S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring BFD on a Port Channel You can configure the BFD session parameters for all BFD sessions on a port channel. For example, if the BFD session for one link on a port channel is up, BFD informs client protocols, such as BGP, that the port channel is up.
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Chapter 7 Configuring Bidirectional Forwarding Detection for BGP Configuring BFD Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 4 Command Purpose show running-config bfd (Optional) Displays the BFD running configuration. Example: switch(config-if)# show running-config bfd Step 5 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 7 Configuring Bidirectional Forwarding Detection for BGP Configuring BFD S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 bfd slow-timer echo-interval Example: switch(config)# bfd slow-timer 2000 Configures the slow timer used in the echo function.
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Chapter 7 Configuring Bidirectional Forwarding Detection for BGP Configuring BFD Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configure the BFD session parameters. See the “Configuring Global BFD Parameters” section on page 7-6 or the “Configuring BFD on an Interface” section on page 7-8. Ensure that these subinterfaces connect to another Cisco NX-OS device. This feature is supported on Cisco NX-OS only. SUMMARY STEPS 1. configure terminal 2.
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Chapter 7 Configuring Bidirectional Forwarding Detection for BGP Configuring BFD S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring BFD on BGP You can configure BFD for the Border Gateway Protocol (BGP). BEFORE YOU BEGIN Ensure that you are in the correct VDC (or use the switchto vdc command). Enable the BFD feature. See the “Enabling the BFD Feature” section on page 7-6. Configure the BFD session parameters.
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Chapter 7 Configuring Bidirectional Forwarding Detection for BGP Verifying the BFD Configuration Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 5 Command Purpose show running-config bgp (Optional) Displays the BGP running configuration. Example: switch(config-router-neighbor)# show running-config bgp Step 6 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 7 Configuring Bidirectional Forwarding Detection for BGP Feature History for BFD S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Feature History for BFD Table 7-2 lists the release history for this feature. Table 7-2 Feature History for BGP Feature Name Releases Feature Information BFD for BGP 5.0(3)U2(2) Added support for BFD for BGP. See Chapter 7, “Configuring Bidirectional Forwarding Detection for BGP” for more information.
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Chapter 7 Configuring Bidirectional Forwarding Detection for BGP Feature History for BFD Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . CH A P T E R 8 Configuring ECMP for Host Routes This chapter describes how to configure the equal-cost multipathing (ECMP) protocol for host routes on the Cisco NX-OS switch.
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Chapter 8 Configuring ECMP for Host Routes Prerequisites for ECMP for Host Routes Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Product License Requirement Cisco NX-OS ECMP for host routes requires no license. Any feature not included in a license package is bundled with the Cisco NX-OS system images and is provided at no extra charge to you. For a complete explanation of the Cisco NX-OS licensing scheme, see the Cisco NX-OS Licensing Guide.
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Chapter 8 Configuring ECMP for Host Routes Configuring ECMP for Host Routes S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 system urpf disable (Optional) Disables URPT globally on the switch.
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Chapter 8 Configuring ECMP for Host Routes Verifying the ECMP for Host Routes Configuration Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 2 Command Purpose no hardware profile unicast enable-host-ecmp Disables ECMP for host routes globally on the switch and removes all associated configuration. Example: switch(config)# no hardware profile unicast enable-host-ecmp Step 3 copy running-config startup-config Saves this configuration change.
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Chapter 8 Configuring ECMP for Host Routes Additional References S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Related Documents Related Topic Document Title ECMP for host routes CLI commands Cisco Nexus 3000 Series Command Reference, Feature History for ECMP for Host Routes Table 8-1 lists the release history for this feature.
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Chapter 8 Configuring ECMP for Host Routes Additional References Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . CH A P T E R 9 Configuring RIP This chapter describes how to configure the Routing Information Protocol (RIP).
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Chapter 9 Configuring RIP Information About RIP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . RIP Overview RIP uses User Datagram Protocol (UDP) data packets to exchange routing information in small internetworks. RIPv2 supports IPv4. RIPv2 uses an optional authentication feature supported by the RIPv2 protocol (see the “RIPv2 Authentication” section on page 9-2).
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Chapter 9 Configuring RIP Information About RIP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Figure 9-1 RIP with Split Horizon Poison Reverse route x route x route x 185058 route x unreachable route x unreachable Router A Router B Router C Router C learns about route X and advertises that route to router B. Router B in turn advertises route X to router A, but sends a route X unreachable update back to router C.
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Chapter 9 Configuring RIP Licensing Requirements for RIP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Cisco NX-OS supports the Equal Cost Multiple Paths (ECMP) feature with up to 16 equal-cost paths in the RIP route table and the unicast RIB. You can configure RIP to load balance traffic across some or all of those paths. Virtualization Support Cisco NX-OS supports multiple instances of the RIP protocol that runs on the same system.
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Chapter 9 Configuring RIP Configuring RIP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 9 Configuring RIP Configuring RIP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 feature rip Enables the RIP feature. Example: switch(config)# feature rip Step 3 show feature (Optional) Displays enabled and disabled features.
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Chapter 9 Configuring RIP Configuring RIP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 router rip instance-tag Example: switch(config)# router RIP Enterprise switch(config-router)# Creates a new RIP instance with the configured instance-tag.
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Chapter 9 Configuring RIP Configuring RIP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 9 Configuring RIP Configuring RIP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 interface interface-type slot/port Enters interface configuration mode. Example: switch(config)# interface ethernet 1/2 switch(config-if)# Step 3 Configures the interface as a Layer 3 routed interface.
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Chapter 9 Configuring RIP Configuring RIP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . SUMMARY STEPS 1. configure terminal 2. interface interface-type slot/port 3. no switchport 4. ip rip authentication mode{text | md5} 5. ip rip authentication key-chain key 6. (Optional) copy running-config startup-config DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode.
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Chapter 9 Configuring RIP Configuring RIP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring a Passive Interface You can configure a RIP interface to receive routes but not send route updates by setting the interface to passive mode. To configure a RIP interface in passive mode, use the following command in interface configuration mode: Command Purpose ip rip passive-interface Sets the interface into passive mode.
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Chapter 9 Configuring RIP Configuring RIP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring Route Redistribution You can configure RIP to accept routing information from another routing protocol and redistribute that information through the RIP network. Redistributed routes can optionally be assigned a default route. BEFORE YOU BEGIN Ensure that you have enabled the RIP feature (see the “Enabling the RIP Feature” section on page 9-5).
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Chapter 9 Configuring RIP Configuring RIP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 5 Command Purpose default-information originate [always] [route-map map-name] (Optional) Generates a default route into RIP, optionally controlled by a route map.
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Chapter 9 Configuring RIP Configuring RIP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . 5. vrf context vrf_name 6. (Optional) address-family ipv4 unicast 7. (Optional) redistribute {bgp as | direct | {eigrp | ospf | ospfv3 | rip} instance-tag | static} route-map map-name 8. interface ethernet slot/port 9. no switchport 10. vrf member vrf-name 11. ip-address ip-prefix/length 12. ip router rip instance-tag 13.
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Chapter 9 Configuring RIP Configuring RIP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 7 Command Purpose redistribute {bgp as | direct | {eigrp | ospf | ospfv3 | rip} instance-tag | static} route-map map-name (Optional) Redistributes routes from other protocols into RIP. See the “Configuring Route Maps” section on page 13-12 for more information about route maps.
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Chapter 9 Configuring RIP Configuring RIP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 9 Configuring RIP Verifying the RIP Configuration S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose ip rip metric-offset value Adds a value to the metric for every router received on this interface. The range is from 1 to 15. The default is 1.
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Chapter 9 Configuring RIP Configuration Examples for RIP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuration Examples for RIP This example creates the Enterprise RIP instance in a VRF and adds Ethernet interface 1/2 to this RIP instance. The example also configures authentication for Ethernet interface 1/2 and redistributes EIGRP into this RIP domain.
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Chapter 9 Configuring RIP Feature History for RIP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Related Documents Related Topic Document Title RIP CLI commands Cisco Nexus 3000 Series Command Reference, Standards Standards Title No new or modified standards are supported by this — feature, and support for existing standards has not been modified by this feature. Feature History for RIP Table 9-2 lists the release history for this feature.
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Chapter 9 Configuring RIP Feature History for RIP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . CH A P T E R 10 Configuring Static Routing This chapter describes how to configure static routing on the switch.
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Chapter 10 Configuring Static Routing Information About Static Routing Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 10 Configuring Static Routing Licensing Requirements for Static Routing S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Remote Next Hops for Static Routes You can specify the next-hop address of a neighboring router which is not directly connected to the router for static routes with remote (non-directly attached) next-hops.
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Chapter 10 Configuring Static Routing Configuring Static Routing Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 10 Configuring Static Routing Configuring Static Routing S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 3 Command Purpose show ip static-route (Optional) Displays information about static routes. Example: switch(config)# show ip static-route Step 4 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 10 Configuring Static Routing Verifying the Static Routing Configuration Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 4 Command Purpose show ip static-route vrf vrf-name (Optional) Displays information on static routes. Example: switch(config-vrf)# show ip static-route Step 5 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 10 Configuring Static Routing Feature History for Static Routing S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Related Documents Related Topic Document Title Static Routing CLI Cisco Nexus 3000 Series Command Reference, Feature History for Static Routing Table 10-2 lists the release history for this feature. Table 10-2 Feature History for Static Routing Feature Name Releases Feature Information Static Routing 5.
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Chapter 10 Configuring Static Routing Feature History for Static Routing Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . CH A P T E R 11 Configuring Layer 3 Virtualization This chapter describes how to configure Layer 3 virtualization.
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Chapter 11 Configuring Layer 3 Virtualization Layer 3 Virtualization Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Each router has a default VRF and a management VRF. All Layer 3 interfaces and routing protocols exist in the default VRF until you assign them to another VRF. The mgmt0 interface exists in the management VRF.With the VRF-lite feature, the switch supports multiple VRFs in customer edge (CE) switches.
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Chapter 11 Configuring Layer 3 Virtualization Layer 3 Virtualization S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . VRF-Aware Services A fundamental feature of the Cisco NX-OS architecture is that every IP-based feature is VRF aware.
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Chapter 11 Configuring Layer 3 Virtualization Layer 3 Virtualization Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Figure 11-2 shows an SNMP server that is reachable over the management VRF. You configure router A to use the management VRF for SNMP server host 192.0.2.1. Figure 11-2 Service VRF Reachability SNMP Server 192.0.2.
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Chapter 11 Configuring Layer 3 Virtualization Licensing Requirements for VRFs S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Figure 11-4 shows an SNMP server that is reachable on the management VRF. You can configure the SNMP server to support only the SNMP notifications from VRF Red, for example.
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Chapter 11 Configuring Layer 3 Virtualization Default Settings Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . • VRF-lite does not support all MPLS-VRF functionality; it does not support label exchange, LDP adjacency, or labeled packets. • Multiple virtual Layer 3 interfaces can be connected to a VRF-lite switch. • The switch supports configuring a VRF by using physical ports, VLAN SVIs, or a combination of both.
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Chapter 11 Configuring Layer 3 Virtualization Configuring VRFs S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . SUMMARY STEPS 1. configure terminal 2. vrf context name 3. ip route {ip-prefix | ip-addr ip-mask} {[next-hop | nh-prefix] | [interface next-hop | nh-prefix]} [tag tag-value [pref] 4. (Optional) show vrf [vrf-name] 5.
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Chapter 11 Configuring Layer 3 Virtualization Configuring VRFs Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . This example shows how to create a VRF and add a static route to the VRF: switch# configure terminal switch(config)# vrf context Enterprise switch(config-vrf)# ip route 192.0.2.
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Chapter 11 Configuring Layer 3 Virtualization Configuring VRFs S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 5 Command Purpose show vrf vrf-name interface interface-type number (Optional) Displays VRF information. Example: switch(config-vrf)# show vrf Enterprise interface ethernet 1/2 Step 6 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 11 Configuring Layer 3 Virtualization Configuring VRFs Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 router ospf instance-tag Example: switch(config-vrf)# router ospf 201 switch(config-router)# Step 3 vrf vrf-name Creates a new OSPFv2 instance with the configured instance tag.
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Chapter 11 Configuring Layer 3 Virtualization Configuring VRFs S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 11 Configuring Layer 3 Virtualization Configuring VRFs Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 4 Command Purpose ip domain-list domain-name [all-vrfs][use-vrf vrf-name] Configures the domain list in the VRF and optionally configures the VRF that Cisco NX-OS uses to reach the domain name listed.
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Chapter 11 Configuring Layer 3 Virtualization Verifying the VRF Configuration S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Verifying the VRF Configuration To display the VRF configuration information, perform one of the following tasks: Command Purpose show vrf [vrf-name] Displays the information for all or one VRF. show vrf [vrf-name] detail Displays detailed information for all or one VRF.
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Chapter 11 Configuring Layer 3 Virtualization Related Topics Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Use the SNMP context lab to access the OSPF-MIB values for the OSPF instance Lab in VRF Red in this example. Related Topics The following topics can give more information on VRFs: • Cisco Nexus 7000 Series NX-OS Fundamentals Configuration Guide, Release 5.x • Cisco Nexus 7000 Series NX-OS System Management Configuration Guide, Release 5.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . CH A P T E R 12 Managing the Unicast RIB and FIB This chapter describes how to manage routes in the unicast Routing Information Base (RIB) and the Forwarding Information Base (FIB) on the Cisco NX-OS switch.
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Chapter 12 Managing the Unicast RIB and FIB Information About the Unicast RIB and FIB Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . The unicast RIB maintains the routing table with directly connected routes, static routes, and routes learned from dynamic unicast routing protocols. The unicast RIB also collects adjacency information from sources such as the Address Resolution Protocol (ARP).
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Chapter 12 Managing the Unicast RIB and FIB Licensing Requirements for the Unicast RIB and FIB S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Licensing Requirements for the Unicast RIB and FIB The following table shows the licensing requirements for this feature: Product License Requirement Cisco NX-OS The unicast RIB and FIB require no license.
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Chapter 12 Managing the Unicast RIB and FIB Managing the Unicast RIB and FIB Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose show ip fib interfaces Displays the FIB interface information for IPv4. Example: switch# show ip fib interfaces show ip fib route Displays the route table for IPv4. Example: switch# show ip fib route show forwarding ipv4 route Displays the route table for IPv4.
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Chapter 12 Managing the Unicast RIB and FIB Managing the Unicast RIB and FIB S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose ip load-sharing address {destination port destination | source-destination [port source-destination]} [universal-id seed] Configures the unicast FIB load-sharing algorithm for data traffic. The universal-id range is from 1 to 4294967295.
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Chapter 12 Managing the Unicast RIB and FIB Managing the Unicast RIB and FIB Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Note Using per-packet load sharing can result in out-of-order packets. Packets for a given pair of source-destination hosts might take different paths and arrive at the destination out of order. Make sure you understand the implications of out-of-order packets to your network and applications.
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Chapter 12 Managing the Unicast RIB and FIB Managing the Unicast RIB and FIB S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose show ip route [route-type | interface int-type number | next-hop] Displays the unicast route table. The route-type argument can be a single route prefix, direct, static, or a dynamic route protocol. Use the ? command to see the supported interfaces.
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Chapter 12 Managing the Unicast RIB and FIB Managing the Unicast RIB and FIB Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose test [ipv4] [unicast] forwarding inconsistency [vrf vrf-name] [module {slot| all}] Starts a Layer 3 consistency check. The vrf-name can be any case-sensitive, alphanumeric string up to 32 characters. The slot range is from 1 to 10.
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Chapter 12 Managing the Unicast RIB and FIB Managing the Unicast RIB and FIB S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Estimating Memory Requirements for Routes You can estimate the memory that a number of routes and next-hop addresses will use.
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Chapter 12 Managing the Unicast RIB and FIB Verifying the Unicast RIB and FIB Configuration Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Verifying the Unicast RIB and FIB Configuration To display the unicast RIB and FIB configuration information, perform one of the following tasks: Command Purpose show forwarding adjacency Displays the adjacency table on a module.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . CH A P T E R 13 Configuring Route Policy Manager This chapter describes how to configure the Route Policy Manager on the Cisco NX-OS switch.
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Chapter 13 Configuring Route Policy Manager Information About Route Policy Manager Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Prefix Lists You can use prefix lists to permit or deny an address or range of addresses. Filtering by a prefix list involves matching the prefixes of routes or packets with the prefixes listed in the prefix list. An implicit deny is assumed if a given prefix does not match any entries in a prefix list.
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Chapter 13 Configuring Route Policy Manager Information About Route Policy Manager S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Match Criteria You can use a variety of criteria to match a route or IP packet in a route map. Some criteria, such as BGP community lists, are applicable only to a specific routing protocol, while other criteria, such as the IP source or the destination address, can be used for any route or IP packet.
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Chapter 13 Configuring Route Policy Manager Information About Route Policy Manager Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . AS-path Lists for BGP You can configure an AS-path list to filter inbound or outbound BGP route updates. If the route update contains an AS-path attribute that matches an entry in the AS-path list, the router processes the route based on the permit or deny condition configured.
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Chapter 13 Configuring Route Policy Manager Licensing Requirements for Route Policy Manager S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Route Redistribution and Route Maps You can use route maps to control the redistribution of routes between routing domains. Route maps match on the attributes of the routes to redistribute only those routes that pass the match criteria.
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Chapter 13 Configuring Route Policy Manager Configuring Route Policy Manager Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 13 Configuring Route Policy Manager Configuring Route Policy Manager S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode.
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Chapter 13 Configuring Route Policy Manager Configuring Route Policy Manager Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . 3. (Optional) show mac-list name 4. (Optional) copy running-config startup-config DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 Step 3 Example: switch(config)# mac-list AllowMac seq 1 permit 0022.5579.a4c1 ffff.ffff.
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Chapter 13 Configuring Route Policy Manager Configuring Route Policy Manager S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 ip as-path access-list name {deny | permit} expression Creates a BGP AS-path list using a regular expression.
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Chapter 13 Configuring Route Policy Manager Configuring Route Policy Manager Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . 2. ip community-list standard list-name {deny | permit} [community-list ] [internet] [local-AS] [no-advertise] [no-export] or ip community-list expanded list-name {deny | permit} expression 3. (Optional) show ip community-list name 4.
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Chapter 13 Configuring Route Policy Manager Configuring Route Policy Manager S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring Extended Community Lists You can use extended community lists to filter BGP routes based on the community attribute. The community number consists of a 6-byte value in the aa4:nn format. The first four bytes represent the autonomous system number, and the last two bytes represent a user-defined network number.
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Chapter 13 Configuring Route Policy Manager Configuring Route Policy Manager Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 3 Command Purpose show ip community-list name (Optional) Displays information about extended community lists. Example: switch(config)# show ip community-list BGPCommunity Step 4 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 13 Configuring Route Policy Manager Configuring Route Policy Manager S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 4 Command Purpose exit (Optional) Exits route-map configuration mode. Example: switch(config-route-map)# exit Step 5 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 13 Configuring Route Policy Manager Configuring Route Policy Manager Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose match ip multicast [source ipsource] [[group ipgroup] [rp iprp]] Matches an IPv4 multicast packet based on the multicast source, group, or rendezvous point. Example: switch(config-route-map)# match ip multicast rp 192.0.2.1 match ip next-hop prefix-list name [name...
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Chapter 13 Configuring Route Policy Manager Configuring Route Policy Manager S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose set as-path {tag | prepend {last-as number | as-1 [as-2...]}} Modifies an AS-path attribute for a BGP route. You can prepend the configured number of last AS numbers or a string of particular AS-path values (as-1 as-2...as-n).
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Chapter 13 Configuring Route Policy Manager Configuring Route Policy Manager Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose set extcommunity generic {transitive | nontransitive} {none | additive] community-1 [community-2...]} Sets the extended community attribute for a BGP route update.
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Chapter 13 Configuring Route Policy Manager Verifying the Route Policy Manager Configuration S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose set metric-type {external | internal | type-1 | type-2} Sets the metric type for the destination routing protocol.
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Chapter 13 Configuring Route Policy Manager Related Topics Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . route-map filterBGP match ip next-hop prefix-list AllowPrefix ip prefix-list AllowPrefix 10 permit 192.0.2.0 eq 24 ip prefix-list AllowPrefix 20 permit 209.165.201.
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Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . CH A P T E R 14 Configuring HSRP This chapter describes how to configure the Hot Standby Router Protocol (HSRP) on the Cisco NX-OS switch.
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Chapter 14 Configuring HSRP Information About HSRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . • HSRP Messages, page 14-4 • HSRP Load Sharing, page 14-4 • Object Tracking and HSRP, page 14-5 • Virtualization Support, page 14-5 HSRP Overview When you use HSRP, you configure the HSRP virtual IP address as the host’s default router (instead of the IP address of the actual router).
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Chapter 14 Configuring HSRP Information About HSRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Figure 14-1 HSRP Topology With Two Enabled Routers Internet or ISP backbone Active router 192.0.2.1 Virtual router 192.0.2.2 Standby router 192.0.2.3 Host A Host B Host C Host D 185061 LAN The virtual router does not physically exist but represents the common default router for interfaces that are configured to provide backup to each other.
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Chapter 14 Configuring HSRP Information About HSRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . HSRP version 2 uses the new IP multicast address 224.0.0.102 to send hello packets instead of the multicast address of 224.0.0.2, which is used by version 1. HSRP version 2 permits an expanded group number range of 0 to 4095 and uses a new MAC address range of 0000.0C9F.F000 to 0000.0C9F.FFFF. HSRP Versions Cisco NX-OS supports HSRP version 1 by default.
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Chapter 14 Configuring HSRP Information About HSRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Figure 14-2 HSRP Load Sharing User Group A Default Gateway = 192.0.2.1 Active Router A Standby Standby Router B Active User Group B Default Gateway = 192.0.2.2 Group B = 192.0.2.2 185059 Group A = 192.0.2.1 Figure 14-2 shows two routers A and B and two HSRP groups. Router A is the active router for group A but is the standby router for group B.
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Chapter 14 Configuring HSRP Licensing Requirements for HSRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Licensing Requirements for HSRP The following table shows the licensing requirements for this feature: Product License Requirement Cisco NX-OS HSRP requires no license. Any feature not included in a license package is bundled with the Cisco NX-OS system images and is provided at no extra charge to you.
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Chapter 14 Configuring HSRP Configuring HSRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 14 Configuring HSRP Configuring HSRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Command Purpose no feature hsrp Disables HSRP. Example: switch(config)# no feature hsrp Configuring the HSRP Version You can configure the HSRP version. If you change the version for existing groups, Cisco NX-OS reinitializes HSRP for those groups because the virtual MAC address changes. The HSRP version applies to all groups on the interface.
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Chapter 14 Configuring HSRP Configuring HSRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 interface type number Enters interface configuration mode. Example: switch(config)# interface ethernet 1/2 switch(config-if)# Step 3 Configures the interface as a Layer 3 routed interface.
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Chapter 14 Configuring HSRP Configuring HSRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . switch(config-if)# no switchport switch(config-if)# ip 192.0.2.2/8 switch(config-if)# hsrp 2 switch(config-if-hsrp)# ip 192.0.2.
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Chapter 14 Configuring HSRP Configuring HSRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . 2. interface interface-type slot/port 3. no switchport 4. hsrp group-number [ipv4] 5. authentication text string or authentication md5 {key-chain key-chain | key-string {0 | 7} text [timeout seconds]} 6. (Optional) show hsrp [group group-number] 7.
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Chapter 14 Configuring HSRP Configuring HSRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 14 Configuring HSRP Configuring HSRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode.
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Chapter 14 Configuring HSRP Configuring HSRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 8 Command Purpose preempt [delay [minimum seconds] [reload seconds] [sync seconds]] Configures the router to take over as the active router for an HSRP group if it has a higher priority than the current active router. This command is disabled by default. The range is from 0 to 3600 seconds.
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Chapter 14 Configuring HSRP Configuring HSRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . To customize HSRP, use the following commands in hsrp configuration mode: Command Purpose name string Specifies the IP redundancy name for an HSRP group. The string is from 1 to 255 characters. The default string has the following format: Example: switch(config-if-hsrp)# name HSRP-1 hsrp--. For example, hsrp-Eth2/1-1.
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Chapter 14 Configuring HSRP Verifying the HSRP Configuration Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Verifying the HSRP Configuration To display the HSRP configuration information, perform one of the following tasks: Command Purpose show hsrp [group group-number] Displays the HSRP status for all groups or one group. show hsrp delay [interface interface-type slot/port] Displays the HSRP delay value for all interfaces or one interface.
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Chapter 14 Configuring HSRP Feature History for HSRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . • MIBs, page 14-17 Related Documents Related Topic Document Title Configuring the Virtual Router Redundancy protocol Chapter 15, “Configuring VRRP” HSRP CLI commands Cisco Nexus 3000 Series Command Reference, MIBs MIBs MIBs Link CISCO-HSRP-MIB To locate and download MIBs, go to the following URL: http://www.cisco.
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Chapter 14 Configuring HSRP Feature History for HSRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 15 Configuring VRRP Information About VRRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . VRRP Operation A LAN client can determine which router should be the first hop to a particular remote destination by using a dynamic process or static configuration.
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Chapter 15 Configuring VRRP Information About VRRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Routers B and C function as backups. If the master fails, the backup router with the highest priority becomes the master and takes over the virtual IP address to provide uninterrupted service for the LAN hosts. When router A recovers, it becomes the r master again. For more information, see the “VRRP Router Priority and Preemption” section.
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Chapter 15 Configuring VRRP Information About VRRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Figure 15-2 Load Sharing and Redundancy VRRP Topology Router A Master for virtual router 1 Backup for virtual router 2 10.0.0.2 129284 10.0.0.1 Router B Backup for virtual router 1 Master for virtual router 2 Client 1 Default gateway = 10.0.0.1 Client 2 Default gateway = 10.0.0.1 Client 3 Default gateway = 10.0.0.2 Client 4 Default gateway = 10.
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Chapter 15 Configuring VRRP Information About VRRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . VRRP Advertisements The VRRP master sends VRRP advertisements to other VRRP routers in the same group. The advertisements communicate the priority and state of the master. Cisco NX-OS encapsulates the VRRP advertisements in IP packets and sends them to the IP multicast address assigned to the VRRP group.
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Chapter 15 Configuring VRRP Licensing Requirements for VRRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Licensing Requirements for VRRP The following table shows the licensing requirements for this feature: Product License Requirement Cisco NX-OS VRRP requires no license. Any feature not included in a license package is bundled with the Cisco NX-OS system images and is provided at no extra charge to you.
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Chapter 15 Configuring VRRP Configuring VRRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 15 Configuring VRRP Configuring VRRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring VRRP Groups You can create a VRRP group, assign the virtual IP address, and enable the group. You can configure one virtual IPv4 address for a VRRP group. By default, the master VRRP router drops the packets addressed directly to the virtual IP address because the VRRP master is only intended as a next-hop router to forward packets.
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Chapter 15 Configuring VRRP Configuring VRRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 interface interface-type slot/port Enters interface configuration mode.
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Chapter 15 Configuring VRRP Configuring VRRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . BEFORE YOU BEGIN Ensure that you have enabled the VRRP feature (see the “Configuring VRRP” section on page 15-7). Ensure that you have configured an IP address on the interface (see the “Configuring IPv4 Addressing” section on page 2-7. SUMMARY STEPS 1. configure terminal 2. interface interface-type slot/port 3. no switchport 4. vrrp number 5.
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Chapter 15 Configuring VRRP Configuring VRRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 6 Step 7 Command Purpose priority level [forwarding-threshold lower lower-value upper upper-value] Example: switch(config-if-vrrp)# priority 60 forwarding-threshold lower 40 upper 50 Sets the priority level used to select the active router in an VRRP group. The level range is from 1 to 254.
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Chapter 15 Configuring VRRP Configuring VRRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 interface interface-type slot/port Enters interface configuration mode.
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Chapter 15 Configuring VRRP Configuring VRRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Ensure that you have configured an IP address on the interface (see the “Configuring IPv4 Addressing” section on page 2-7. SUMMARY STEPS 1. configure terminal 2. interface interface-type slot/port 3. no switchport 4. vrrp number 5. shutdown 6. advertisement-interval seconds 7. no shutdown 8. (Optional) show vrrp 9.
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Chapter 15 Configuring VRRP Configuring VRRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 7 Command Purpose no shutdown Enables the VRRP group. Disabled by default.
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Chapter 15 Configuring VRRP Configuring VRRP S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode. Example: switch# configure terminal switch(config)# Step 2 interface interface-type slot/port Enters interface configuration mode. Example: switch(config)# interface ethernet 2/1 switch(config-if)# Step 3 Configures the interface as a Layer 3 routed interface.
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Chapter 15 Configuring VRRP Configuring VRRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Note For interface state tracking to function, you must enable preemption on the interface. Note VRRP does not support Layer 2 interface tracking. BEFORE YOU BEGIN Ensure that you have enabled the VRRP feature (see the “Configuring VRRP” section on page 15-7).
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Chapter 15 Configuring VRRP Verifying the VRRP Configuration S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 5 Command Purpose shutdown Disables the VRRP group. Disabled by default. Example: switch(config-if-vrrp)# shutdown switch(config-if-vrrp)# Step 6 track interface type number priority value Enables interface priority tracking for a VRRP group. The priority range is from 1 to 254.
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Chapter 15 Configuring VRRP Configuration Examples for VRRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Use the clear vrrp vr command to clear the IPv4 VRRP statistics for a specified interface. Configuration Examples for VRRP In this example, Router A and Router B each belong to three VRRP groups. In the configuration, each group has the following properties: • Group 1: – Virtual IP address is 10.1.0.10.
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Chapter 15 Configuring VRRP Additional References S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . no shutdown vrrp 5 priority 200 advertisement-interval 30 address 10.2.0.50 no shutdown vrrp 100 no preempt address 10.2.0.
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Chapter 15 Configuring VRRP Feature History for VRRP Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . CH A P T E R 16 Configuring Object Tracking This chapter describes how to configure object tracking on Cisco NX-OS switches.
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Chapter 16 Configuring Object Tracking Information About Object Tracking Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . • Hot Standby Redundancy Protocol (HSRP) • Virtual Router Redundancy Protocol (VRRP) The object tracking monitors the status of the tracked objects and communicates any changes made to interested clients.
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Chapter 16 Configuring Object Tracking Licensing Requirements for Object Tracking S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Licensing Requirements for Object Tracking The following table shows the licensing requirements for this feature: Product License Requirement Cisco NX-OS Object tracking requires no license.
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Chapter 16 Configuring Object Tracking Configuring Object Tracking Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring Object Tracking for an Interface You can configure Cisco NX-OS to track the line protocol or IPv4 routing state of an interface. SUMMARY STEPS 1. configure terminal 2. track object-id interface interface-type number {ip routing | line-protocol} 3. (Optional) show track [object-id] 4.
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Chapter 16 Configuring Object Tracking Configuring Object Tracking S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring Object Tracking for Route Reachability You can configure Cisco NX-OS to track the existence and reachability of an IP route. SUMMARY STEPS 1. configure terminal 2. track object-id ip route prefix/length reachability 3. (Optional) show track [object-id] 4.
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Chapter 16 Configuring Object Tracking Configuring Object Tracking Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring an Object Track List with a Boolean Expression You can configure an object track list that contains multiple tracked objects. A tracked list contains one or more objects. The Boolean expression enables two types of calculation by using either "and" or "or" operators.
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Chapter 16 Configuring Object Tracking Configuring Object Tracking S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 4 Command Purpose show track (Optional) Displays object tracking information. Example: switch(config-track)# show track Step 5 copy running-config startup-config (Optional) Saves this configuration change.
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Chapter 16 Configuring Object Tracking Configuring Object Tracking Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 3 Command Purpose threshold percentage up up-value down down-value Configures the threshold percent for the tracked list. The range from 0 to 100 percent.
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Chapter 16 Configuring Object Tracking Configuring Object Tracking S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . DETAILED STEPS Step 1 Command Purpose configure terminal Enters configuration mode.
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Chapter 16 Configuring Object Tracking Configuring Object Tracking Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring an Object Tracking Delay You can configure a delay for a tracked object or an object track list that delays when the object or list triggers a stage change. The tracked object or track list starts the delay timer when a state change occurs but does not recognize a state change until the delay timer expires.
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Chapter 16 Configuring Object Tracking Configuring Object Tracking S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Step 4 Command Purpose delay {up up-time [down down-time] | down down-time [up up-time]} Configures the object delay timers. The range is from 0 to 180 seconds. Example: switch(config-track)# delay up 20 down 30 Step 5 (Optional) Displays object tracking information.
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Chapter 16 Configuring Object Tracking Configuring Object Tracking Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Configuring Object Tracking for a Nondefault VRF You can configure Cisco NX-OS to track an object in a specific VRF. SUMMARY STEPS 1. configure terminal 2. track object-id ip route prefix/length reachability 3. vrf member vrf-name 4. (Optional) show track [object-id] 5.
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Chapter 16 Configuring Object Tracking Verifying the Object Tracking Configuration S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Chapter 16 Configuring Object Tracking Feature History for Object Tracking Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Related Documents Related Topic Document Title Object Tracking CLI commands Cisco Nexus 3000 Series Command Reference, Standards Standards Title No new or modified standards are supported by this — feature, and support for existing standards has not been modified by this feature.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . A P P E N D I X A IETF RFCs This appendix lists the IETF RFCs supported in Cisco NX-OS Release 5.0(3)U1(1) and NX-OS Release 5.0(3)U1(2).
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Appendix A IETF RFCs Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . GLOSSARY A ABR See area border router. address family A specific type of network addressing supported by a routing protocol. Examples include IPv4 unicast and IPv4 multicast. adjacency Two OSPF routers that have compatible configurations and have synchronized their link-state databases. administrative distance A rating of the trustworthiness of a routing information source.
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Glossary Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . bandwidth The available traffic capacity of a link. BDR Backup designated router. An elected router in a multi-access OSPF network that acts as the backup if the designated router fails. All neighbors form adjacencies with the backup designated router (BDR) as well as the designated router. BGP Border Gateway Protocol. BGP is an interdomain or exterior gateway protocol.
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Glossary S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . E eBGP External Border Gateway Protocol (BGP). Operates between external systems. EIGRP Enhanced Interior Gateway Protocol. A Cisco routing protocol that uses the Diffusing Update Algorithm to provide fast convergence and minimized bandwidth utilization. F feasible distance The lowest calculated distance to a network destination in EIGRP.
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Glossary Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . IGP Interior gateway protocol. Used between routers within the same autonomous system. instance An independent, configurable entity, typically a protocol. IP tunnels Internet Protocol version 4. IPv4 K A special message sent between routing peers to verify and maintain communications between the pair.
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Glossary S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . N network layer reachability information BGP network layer reachability information (NRLI). Contains the a list of network IP addresses and network masks for networks that are reachable from the advertising BGP peer. next hop The next router that a packet is sent to on its way to the destination address. NSSA Not-So-Stubby-Area. Limits AS external LSAs in an OSPF area.
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Glossary Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . S SPF algorithm Shortest Path First algorithm. Dijkstra’s algorithm used by OSPF to determine the shortest route through a network to a particular destination. split horizon Routes learned from an interface are not advertised back along the interface they were learned on, preventing the router from seeing its own route updates.
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S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . INDEX description A ABR 3-4 B address formats IPv4 2-2 bandwidth address resolution protocol.
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Index Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Index S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . C communication cost 1-4 community lists disabling fast external failover 6-23 disabling single-hop checking 6-22 limiting the AS-path attribute 6-24 eBGP AS confederations. See AS confederations configuring 13-9, 13-11 ECMP.
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Index Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Index S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Index Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . track list M 16-2 verifying configuration MAC lists 16-13 virtualization support description 13-2 Open Shortest Path First.
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Index S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Index Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .
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Index S e n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m . Routing Information Protocol. See RIP U routing metrics description uRIB 1-2 clearing routes routing protocols administrative distance description 1-7 12-9 12-1 comparing link-state algorithms to distance vector algorithms 1-9 displaying displaying (example) 12-7 convergence.
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Index Se n d d o c u m e n t c o m m e n t s t o n ex u s 3 k - d o c f e e d b a ck @ c i s c o . c o m .