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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 e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m . Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
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OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. Cisco and the Cisco Logo are trademarks of Cisco Systems, Inc. and/or its affiliates in the U.S. and other countries. A listing of Cisco's trademarks can be found at www.cisco.com/go/trademarks.
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Static and Dynamic Entries in the ARP Cache Devices that do not use ARP Reverse ARP Proxy ARP Local Proxy ARP Gratuitous ARP ICMP Virtualization Support Licensing Requirements for IPv4 Prerequisites for IPv4 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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Configuring DNS Clients Configuring the DNS Client Configuring Virtualization Verifying the DNS Client Configuration DNS Client Example Configuration Default Settings Additional References Related Documents Standards Feature History for DNS Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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5-13 Standards 5-13 Feature History for WCCPv2 5-13 Routing Configuring OSPFv2 C H A P T E R Information About OSPFv2 Hello Packet Neighbors Adjacency Designated Routers Areas Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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Configuring Stub Areas 6-25 Configuring a Totally Stubby Area 6-26 Configuring NSSA 6-27 Configuring Virtual Links 6-29 Configuring Redistribution 6-31 Limiting the Number of Redistributed Routes 6-33 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x viii OL-20002-02...
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Address Family Support Advanced Features Stub Area Not-So-Stubby Area Virtual Links 7-10 Route Redistribution 7-10 Route Summarization 7-10 High Availability and Graceful Restart 7-11 Multiple OSPFv3 Instances 7-12 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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MIBs 7-43 Feature History for OSPFv3 7-43 Configuring EIGRP C H A P T E R Information About EIGRP EIGRP Components Reliable Transport Protocol Neighbor Discovery and Recovery Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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Adjusting the Interval Between Hello Packets and the Hold Time 8-25 Disabling Split Horizon 8-25 Tuning EIGRP 8-26 Configuring Virtualization for EIGRP 8-28 Verifying EIGRP Configuration 8-30 Displaying EIGRP Statistics 8-30 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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Configuring IS-IS Authentication in an Area 9-13 Configuring IS-IS Authentication on an Interface 9-14 Configuring a Mesh Group 9-16 Configuring a Designated Intermediate System 9-16 Configuring Dynamic Host Exchange 9-16 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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BGP and the Unicast RIB 10-7 BGP Virtualization 10-7 Licensing Requirements for Basic BGP 10-7 Prerequisites for BGP 10-7 Guidelines and Limitations for BGP 10-8 CLI Configuration Modes 10-8 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x xiii OL-20002-02...
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C H A P T E R Layer 3 Virtualization 14-1 Overview of Layer 3 Virtualization 14-1 VRF and Routing 14-2 VRF-Aware Services 14-3 Reachability 14-4 Filtering 14-4 Combining Reachability and Filtering 14-5 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x xvii OL-20002-02...
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Returning the TCAM to Default Settings 15-11 Estimating Memory Requirements for Routes 15-12 Clearing Routes in the Unicast RIB 15-13 Verifying the Unicast RIB and FIB 15-13 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x xviii OL-20002-02...
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Related Documents 16-19 Standards 16-19 Feature History for Route Policy Manager 16-19 Configuring Policy-Based Routing 17-1 C H A P T E R Information About Policy Based Routing 17-1 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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Configuring HSRP Object Tracking 19-12 Configuring the HSRP Priority 19-14 Customizing HSRP 19-15 Configuring Extended Hold Timers for HSRP 19-16 Verifying HSRP Configuration 19-17 HSRP Example Configuration 19-17 Default Settings 19-18 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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Related Documents 20-22 Feature History for VRRP 20-22 Configuring Object Tracking 21-1 C H A P T E R Information About Object Tracking 21-1 Object Tracking Overview 21-2 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x xxii OL-20002-02...
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L O S S A R Y Configuration Limits for Cisco NX-OS Layer 3 Unicast Features, Release 4.x A P P E N D I X N D E X Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x xxiii OL-20002-02...
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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 e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m . Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x. The latest version of this document is available at the following Cisco website: http://www.cisco.com/en/US/docs/switches/datacenter/sw/4_2/nx-os/unicast/configuration/guide/l3_nx os-book.html To check for additional information about Cisco NX-OS Release 4.2 , see the Cisco NX-OS Release Notes available at the following Cisco website: http://www.cisco.com/en/US/docs/switches/datacenter/sw/4_2/nx-os/release/notes/42_nx-os_release_n ote.html...
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Chapter 8, “Configuring EIGRP” VRF. EIGRP Added support for EIGRP4-MIB 4.0(3) Chapter 8, “Configuring EIGRP” EIGRP Modified the default EIGRP maximum paths to 8. 4.0(2) Chapter 8, “Configuring EIGRP” Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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IPv4 and IPv6 networks. Chapter 11, “Configuring Advanced BGP” Describes how to configure advanced features for the BGP routing protocol for IPv4 and IPv6 networks, including route redistribution and route aggregation. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
Optional alternative keywords are grouped in brackets and separated by vertical bars. string A nonquoted set of characters. Do not use quotation marks around the string or the string will include the quotation marks. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
Obtaining Documentation and Submitting a Service Request For information on obtaining documentation, submitting a service request, and gathering additional information, see the monthly What’s New in Cisco Product Documentation, which also lists all new and revised Cisco technical documentation, at: http://www.cisco.com/en/US/docs/general/whatsnew/whatsnew.html...
S e 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 7 k - d o c f e e d b a c k @ c i s c o . c o m . C H A P T E R Overview This chapter introduces the underlying concepts for Layer 3 unicast routing protocols in Cisco NX-OS. This chapter includes the following sections: Information About Layer 3 Unicast Routing, page 1-1 •...
The next hop might be the ultimate destination host or another router that executes the same switching decision process. As the packet moves through the internetwork, its physical address changes, but its protocol address remains constant (see Figure 1-1). Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
For example, the line delay for a private line might be longer than a public line, but you can send packets over your private line rather than through the public lines that cost money for usage time. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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. If loopback0 does not exist, then Cisco •...
The number of paths used is limited by the number of entries that the routing protocol puts in the routing table. Cisco NX-OS supports up to 16 paths to a destination.
In this network topology, the remote router does not need to receive routes that have been learned from other Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
BGP is an example of an exterior gateway protocol. Routing protocols used within an autonomous system are called interior gateway protocols or intradomain protocols. EIGRP and OSPF are examples of interior gateway protocols. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
However, link-state algorithms require more CPU power and memory than distance vector algorithms. Link-state algorithms can be more expensive to implement and support. Link-state protocols are generally more scalable than distance vector protocols. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
VRF. A VRF belongs to one VDC. Each VDC can support multiple VRFs. For more information, Chapter 14, “Configuring Layer 3 Virtualization.” See to the Cisco Nexus 7000 Series NX-OS Virtual Device Context Configuration Guide, Release 4.x for details on VDCs.
• Hardware Forwarding, page 1-12 Software Forwarding, page 1-12 • Unicast RIB The Cisco NX-OS forwarding architecture consists of multiple components, as shown in Figure 1-4. Figure 1-4 Cisco NX-OS Forwarding Architecture The unicast RIB exists on the active supervisor. It maintains the routing table with directly connected routes, static routes, and routes learned from dynamic unicast routing protocols.
Software Forwarding The software forwarding path in Cisco NX-OS is used mainly to handle features that are not supported in hardware or to handle errors encountered during hardware processing. Typically, packets with IP options or packets that need fragmentation are passed to the CPU on the active supervisor. All packets that should be switched in software or terminated go to the supervisor.
Link information consists of the link type, the link metric, and the neighbor router connected to the link. The advertisements that contain this link information are called link-state advertisements. For more information, see Chapter 6, “Configuring OSPFv2.” Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 1-13 OL-20002-02...
The EIGRP protocol is a unicast routing protocol that has the characteristics of both distance vector and link-state routing protocols. It is an improved version of IGRP, which is a Cisco proprietary routing protocol. EIGRP relies on its neighbors to provide the routes, typical to a distance vector routing protocol.
NX-OS supports Virtual Device Contexts (VDCs) which allow you to create separate virtual systems within a Cisco NX-OS system. Each VDC is isolated from the others, which means that a problem in one VDC does not affect any other VDCs. VDCs are also secure from the other. You can assign separate network operators to each VDC and these network operators cannot control or view the configuration of a different VDC.
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Cisco Nexus 7000 Series NX-OS Multicast Routing Configuration Guide, Release 4.x Cisco Nexus 7000 Series NX-OS High Availability and Redundancy Guide • Cisco Nexus 7000 Series NX-OS Virtual Device Context Configuration Guide, Release 4.x • Exploring Autonomous System Numbers: •...
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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 e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m . A R T...
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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 e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m .
Subnet masks are 32-bit values that allow the recipient of IP packets to distinguish the network ID portion of the IP address from the host ID portion of the IP address. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
S e 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 7 k - d o c f e e d b a c k @ c i s c o . c o m . The IP feature in the Cisco NX-OS system is responsible for handling IPv4 packets that terminate in the...
ARP to obtain the MAC address of the destination device and delivers the packet. ARP is enabled by default. In Cisco NX-OS Release 4.1(4) and later, the default system-defined CoPP policy rate-limits ARP broadcast packets bound for the supervisor module. The default system-defined CoPP policy prevents an ARP broadcast storm from affecting the control plane traffic, but does not affect bridged packets.
Each server must be configured with a table of static mappings between the hardware addresses and • IP addresses. Maintenance of the IP addresses is difficult. RARP only provides IP addresses of the hosts and not subnet masks or default gateways. • Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
Gratuitous ARP Gratuitous ARP sends a request with identical source IP address and destination IP address to detect duplicate IP addresses. Cisco NX-OS Release 4.0(3) and later releases support enabling or disabling gratuitous ARP requests or ARP cache updates. ICMP You can use ICMP to provide message packets that report errors and other information that is relevant to IP processing.
License Requirement NX-OS IP 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 NX-OS licensing scheme, see the Cisco NX-OS Licensing Guide.
S e 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 7 k - d o c f e e d b a c k @ c i s c o . c o m . If you are familiar with the Cisco IOS CLI, be aware that the Cisco NX-OS commands for this feature Note might differ from the Cisco IOS commands that you would use.
Configuring IP Packet Verification Cisco NX-OS supports an Intrusion Detection System (IDS) that checks for IP packet verification. You can enable or disable these IDS checks. To enable IDS checks, use the following commands in global configuration mode:...
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 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 2-14 OL-20002-02...
Parameters Default proxy ARP disabled Additional References For additional information related to implementing IP, see the following sections: • Related Documents, page 2-16 Standards, page 2-16 • Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 2-15 OL-20002-02...
Changed plaform ip verify command to hardware ip verify command. 4.0(3) Added support for gratuitous ARP. The following command was added: ip arp gratuitous {request | update} • 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 2-16 OL-20002-02...
(RIP), Integrated Intermediate System-to-Intermediate System (IS-IS), Open Shortest Path First (OSPF) for IPv6, and multiprotocol Border Gateway Protocol (BGP). This section includes the following topics: IPv6 Address Formats, page 3-2 • Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
The hexadecimal letters in IPv6 addresses are not case sensitive. Table 3-1 Compressed IPv6 Address Formats IPv6 Address Type Preferred Format Compressed Format Unicast 2001:0:0:0:0DB8:800:200C:417A 2001::0DB8:800:200C:417A Multicast FF01:0:0:0:0:0:0:101 FF01::101 Loopback 0:0:0:0:0:0:0:0:1 Unspecified 0:0:0:0:0:0:0:0:0 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
ID. The IPv6 global unicast address allocation uses the range of addresses that start with binary value 001 (2000::/3). Figure 3-1 shows the structure of an aggregatable global address. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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(picked randomly and, if necessary, reconstructed) until both identifiers are unique. The first MAC address in the router is used as the identifier for interfaces using PPP. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
IPv4 and IPv6 protocol stacks and are used in automatic tunnels. Figure 3-3 shows the structure of an IPv4-compatible IPv6 address and a few acceptable formats for the address. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
Global ID — 41-bit global identifier used to create a globally unique prefix. • Subnet ID — 16-bit subnet ID is an identifier of a subnet within the site. • • Interface ID — 64-bit IID Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
1, 2, 5, 8, or E, respectively. For example, a multicast address with the prefix FF02::/16 is a permanent multicast address with a link scope. Figure 3-6 shows the format of the IPv6 multicast address. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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Prefix Interface ID 24 bits Solicited-node multicast address FF02 Lower 24 128 bits Note IPv6 has no broadcast addresses. IPv6 multicast addresses are used instead of broadcast addresses. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
Payload Length Similar to the Total Length field in the IPv4 packet header. The Payload Length field indicates the total length of the data portion of the packet. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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Typically, the final extension header has a Next Header field of a transport-layer protocol, such as TCP or UDP. Figure 3-10 shows the IPv6 extension header format. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 3-10 OL-20002-02...
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Upper-layer headers 6 (TCP) Headers that are used inside a packet to transport the data. The two main transport protocols are TCP and 17 (UDP) UDP. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 3-11 OL-20002-02...
IPv6 links. CDP IPv6 Address Support You can use the Cisco Discovery Protocol (CDP) IPv6 address support for neighbor information feature to transfer IPv6 addressing information between two Cisco devices. Cisco Discovery Protocol support for IPv6 addresses provides IPv6 information to network management products and troubleshooting tools.
The destination address is the solicited-node multicast address that corresponds to the IPv6 address of the destination node. The neighbor solicitation message also includes the link-layer address of the source node. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 3-13 OL-20002-02...
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1 are sent only in response to a neighbor solicitation message). Unsolicited messages confirm only the one-way path from the source to the destination node; solicited neighbor advertisement messages indicate that a path is working in both directions. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 3-14 OL-20002-02...
Additional information for hosts, such as the hop limit and MTU that a host should use in packets • that it originates Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 3-15 OL-20002-02...
Routers send neighbor redirect messages to inform hosts of better first-hop nodes on the path to a destination (see Figure 3-14). A value of 137 in the Type field of the ICMP packet header identifies an IPv6 neighbor redirect message. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 3-16 OL-20002-02...
IPv6 supports Virtual Routing and Forwarding instances (VRFs). VRFs exist within virtual device contexts (VDCs). By default, Cisco NX-OS places you in the default VDC and default VRF unless you specifically configure another VDC and VRF. For more information, see the Cisco Nexus 7000 Series NX-OS Virtual Device Context Configuration Guide, Release 4.x and see...
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• Configuring IPv6 Packet Verification, page 3-23 • If you are familiar with the Cisco IOS CLI, be aware that the Cisco NX-OS commands for this feature Note might differ from the Cisco IOS commands that you would use. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
IPv6 is enabled on the interface. Enables IPv6 processing on an interface without configuring an IPv6 address. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 3-19 OL-20002-02...
BEFORE YOU BEGIN Ensure that you are in the correct VDC (or use the switchto vdc command). You must first enable IPv6 on the interface. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 3-20 OL-20002-02...
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Last Neighbor-Solicitation sent: never Last Neighbor-Advertisement sent: never Last Router-Advertisement sent:never Next Router-Advertisement sent in: 0.000000 Router-Advertisement parameters: Periodic interval: 200 to 600 seconds Send "Managed Address Configuration" flag: false Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 3-21 OL-20002-02...
Enables ICMPv6 redirect messages to be sent. ipv6 nd retrans-timer Configures the advertised time between neighbor solicitation messages in router advertisements. ipv6 nd suppress-ra Suppresses IPv6 router advertisement transmissions on a LAN interface. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 3-22 OL-20002-02...
S e 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 7 k - d o c f e e d b a c k @ c i s c o . c o m . Configuring IPv6 Packet Verification Cisco NX-OS supports an Intrusion Detection System (IDS) that checks for IPv6 packet verification. You can enable or disable these IDS checks.
1000 milliseconds Additional References For additional information related to implementing IPv6, see the following sections: Related Documents, page 3-25 • Standards, page 3-25 • Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 3-24 OL-20002-02...
Changed plaform {ip | ipv6} verify command to hardware {ip | ipv6} verify command. IPv6 address 4.0(3) Added tag keyword to ipv6 address command. IPv6 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 3-25 OL-20002-02...
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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 e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m . Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
This allows local control of the segments of the network through a client-server scheme. The DNS system can locate a network device by translating the host name of the device into its associated IP address. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
For example, Cisco is a commercial organization that the Internet identifies by a com domain, so its domain name is cisco.com. A specific host name in this domain, the File Transfer Protocol (FTP) system, for example, is identified as ftp.cisco.com.
• Cisco NX-OS Virtual Device Context Configuration Guide). Configuration Guidelines and Limitations You configure the DNS client in a specific VRF. If you do not specify a VRF, Cisco NX-OS uses the default VRF. Configuring DNS Clients This section describes how to configure DNS clients and includes the following topics: Configuring the DNS Client, page 4-3 •...
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You can optionally define a VRF that Cisco NX-OS Example: uses to reach this name server if it cannot be reached switch(config)# ip name-server in the VRF that you configured this name server under. 192.0.2.22 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
[ se-vrf vrf-name] ip domain-list name [use-vrf vrf-name] ip name-server server-address1 [server-address2... server-address6] [use-vrf vrf-name] ip domain lookup show hosts copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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VRF that you configured this name server under. 192.0.2.22 Step 5 (Optional) Enables DNS-based address translation for ip domain-lookup this VRF. Enabled by default. Example: switch(config-vrf)# ip domain-lookup Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
The example also configures the addresses of the name servers and the default domain name. ip domain lookup ip name-server 192.168.1.111 192.168.1.2 ip domain name cisco.com Default Settings Table 4-1 lists the default settings for DNS Client parameters. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
Feature History for DNS Table 4-2 lists the release history for this feature. Table 4-2 Feature History for DNS Feature Name Releases Feature Information 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
• Information About WCCPv2 WCCPv2 specifies interactions between one or more Cisco NX-OS routers and one or more cache engines. WCCPv2 transparently redirects selected types of traffic through a group of routers. The selected traffic is redirected to a group of cache engines to optimize resource usage and lower response times.
S e 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 7 k - d o c f e e d b a c k @ c i s c o . c o m . WCCPv2 Overview WCCPv2 enables the Cisco NX-OS router to transparently redirect packets to cache engines. WCCPv2 does not interfere with normal router operations. Using WCCPv2, the router can redirect requests on configured interfaces to cache engines rather than to intended host sites.
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You configure each cache engine with a list of routers. Step 1 Each cache engine announces its presence and a list of all routers with which it has established Step 2 communications. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
Cisco NX-OS uses the mask method to assign traffic. The designated cache engine assigns the mask and value sets to the router in the WCCP Redirect Assignment message. The router matches these mask and value sets to the source IP address, destination IP address, source port, and destination port of each packet.
• example, when IP authentication has been turned on. WCCPv2 negotiates the packet return method between the router and the cache engine. Cisco NX-OS uses this traffic return method for all cache engines in a service group. WCCPv2 returns packets using the following forwarding method: Destination MAC rewrite—WCCPv2 replaces the destination MAC address of the packet with the...
• page 5-7). You can only configure WCCPv2 on Layer 3 or VLAN interfaces (see the Cisco Nexus 7000 Series • NX-OS Interfaces Configuration Guide, Release 4.x). If you configure VDCs, install the Advanced Services license and enter the desired VDC (see the •...
• Configuring WCCPv2 in a VRF, page 5-10 • If you are familiar with the Cisco IOS CLI, be aware that the Cisco NX-OS commands for this feature Note might differ from the Cisco IOS commands that you would use.
Ensure that you are in the correct VDC (or use the switchto vdc command). Enable the WCCPv2 feature (see the “Enabling the WCCPv2 Feature” section on page 5-7). Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
Applying WCCPv2 Redirection to an Interface To apply WCCPv2 redirection on an interface, use the following commands in interface configuration mode: Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
1/2 ip wccp web-cache redirect out no shutdown Note See the Cisco Nexus 7000 Series NX-OS Security Configuration Guide, Release 4.x for information about IP access lists. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 5-12...
Feature History for WCCPv2 Table 5-2 lists the release history for this feature. Table 5-2 Feature History for WCCPv2 Feature Name Releases Feature Information WCCPv2 4.2(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 5-13 OL-20002-02...
S e 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 7 k - d o c f e e d b a c k @ c i s c o . c o m . Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
You can divide OSPFv2 networks into areas. Routers send most LSAs only within one area, which reduces the CPU and memory requirements for an OSPF-enabled router. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
The two OSPFv2 interfaces must match the following criteria: Hello interval • Dead interval • Area ID (see the “Areas” section on page 6-4) • Authentication • Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
The routers follow an election procedure based on which routers declare themselves in the DR and BDR fields and the priority field in the Hello packet. As a final tie breaker, OSPFv2 chooses the highest router IDs as the DR and BDR. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
ID of 0. If you have more than one area, then one or more routers become area border routers (ABRs). An ABR connects to both the backbone area and at least one other defined area (see Figure 6-2). Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
By default, LSAs with link-state refresh times within four minutes of each other are grouped together. You should lower this value for large link-state databases or raise it for smaller databases to optimize the OSPFv2 load on your network. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
MaxAge. Routers flood a repeat of the LSA every 30 minutes to prevent accurate link-state information from being aged out. Cisco NX-OS supports the LSA grouping feature to prevent all LSAs from refreshing at the same time. For more information, see the “Flooding and LSA Group Pacing”...
You should use MD5 authentication to authenticate OSPFv2 messages. You configure a password that is shared at the local router and all remote OSPFv2 neighbors. For each OSPFv2 message, Cisco NX-OS creates an MD5 one-way message digest based on the message itself and the encrypted password. The interface sends this digest with the OSPFv2 message.
Virtual links allow you to connect an OSPFv2 area ABR to a backbone area ABR when a direct physical connection is not available. Figure 6-4 shows a virtual link that connects Area 3 to the backbone area through Area 5. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
The two types of summarization are as follows: Inter-area route summarization • External route summarization • Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-10 OL-20002-02...
Summarizing overlapping ranges from two different routers could cause packets to be sent to the wrong destination. Configure external route summarization on ASBRs that are redistributing routes into OSPF. When you configure a summary address, Cisco NX-OS automatically configures a discard route for the summary address to prevent routing black holes and route loops.
OSPFv2 interface. All remote links are marked with the maximum cost (0xFFFF). Multiple OSPFv2 Instances Cisco NX-OS supports multiple instances of the OSPFv2 protocol that run on the same node. You cannot configure multiple instances over the same interface. By default, every instance uses the same system router ID.
Cisco NX-OS displays areas in dotted decimal notation regardless of whether you enter the area in • decimal or dotted decimal notation. If you are familiar with the Cisco IOS CLI, be aware that the Cisco NX-OS commands for this feature Note might differ from the Cisco IOS commands that you would use.
(Optional) Saves this configuration change. copy running-config startup-config Example: switch(config)# copy running-config startup-config Use the no feature ospf command to disable the OSPFv2 feature and remove all associated configuration. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-14 OL-20002-02...
OSPFv2 must be able to obtain a router identifier (for example, a configured loopback address) or you must configure the router ID option. Ensure that you are in the correct VDC (or use the switchto vdc command). Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-16 OL-20002-02...
Ensure that you are in the correct VDC (or use the switchto vdc command). SUMMARY STEPS config t interface interface-type slot/port ip address ip-prefix/length ip router ospf instance-tag area area-id [secondaries none] Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-17 OL-20002-02...
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Configures the OSPFv2 dead interval, in seconds. ip ospf dead-interval seconds The range is from 1 to 65535. The default is four Example: times the hello interval, in seconds. switch(config-if)# ip ospf dead-interval Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-18 OL-20002-02...
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. See the Cisco NX-OS Security Configuration Guide. For OSPFv2, the key identifier in the key key-id command supports values from 0 to 255 only.
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1 to 255. The MD5 option 0 configures switch(config-if)# ip ospf the password in clear text and 3 configures the pass key message-digest-key 21 md5 0 mypass as 3DES encrypted. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-20 OL-20002-02...
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. See the Cisco NX-OS Security Configuration Guide. For OSPFv2, the key identifier in the key key-id command supports values from 0 to 255 only.
Summarization” section on page 6-35. Filter list—Filters the Network Summary (type 3) LSAs on an ABR that are allowed in from an • external area. ASBRs also support filter lists. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-23 OL-20002-02...
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The following example shows how to configure a filter list in area 0.0.0.10: switch# config t switch(config)# router ospf 201 switch(config-router)# area 0.0.0.10 filter-list route-map FilterLSAs in switch(config-router)# copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-24 OL-20002-02...
Ensure that you are in the correct VDC (or use the switchto vdc command). SUMMARY STEPS config t router ospf instance-tag area area-id stub area area-id default-cost cost show ip ospf instance-tag copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-25 OL-20002-02...
You can create a totally stubby area and prevent all summary route updates from going into the stub area. To create a totally stubby area, use the following command in router configuration mode: Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-26...
[no-redistribution] [default-information-originate [route-map map-name]] [no-summary] [translate type7 {always | never} [suppress-fa]] area area-id default-cost cost show ip ospf instance-tag copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-27 OL-20002-02...
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The following example shows how to create an NSSA that filters external routes and blocks all summary route updates: switch# config t switch(config)# router ospf 201 switch(config-router)# area 0.0.0.10 nssa route-map ExternalFilter no-summary switch(config-router)# copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-28 OL-20002-02...
Ensure that you are in the correct VDC (or use the switchto vdc command). SUMMARY STEPS config t router ospf instance-tag area area-id virtual-link router-id show ip ospf virtual-link [brief] copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-29 OL-20002-02...
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50 (Optional) Configures the OSPFv2 hello interval, in hello-interval seconds seconds. The range is from 1 to 65535. The default is 10 Example: seconds. switch(config-router-vlink)# hello-interval 25 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-30 OL-20002-02...
Default information originate ignores match statements in the optional route map. Note Default metric—Sets all redistributed routes to the same cost metric. • If you redistribute static routes, Cisco NX-OS also redistributes the default static route. Note BEFORE YOU BEGIN Ensure that you have enabled the OSPF feature (see the “Enabling the OSPFv2 Feature”...
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0.0.0. even if the route does not exist in the RIB. DefaultRouteFilter route-map—Generate the default route if the • route map returns true. This command ignores match statements in Note the route map. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-32 OL-20002-02...
{bgp id | direct| eigrp id | isis id | ospf id | rip id | static} route-map map-name redistribute maximum-prefix max [threshold] [warning-only | withdraw [num-retries timeout]] show running-config ospf Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-33 OL-20002-02...
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The following example shows how to limit the number of redistributed routes into OSPF: switch# config t switch(config)# router ospf 201 switch(config-router)# redistribute bgp route-map FilterExternalBGP switch(config-router)# redistribute maximum-prefix 1000 75 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-34 OL-20002-02...
[no-advertise | tag tag] addresses and optionally assigns a tag for this summary address that can be used for redistribution Example: with route maps. switch(config-router)# summary-address 10.5.0.0/16 tag 2 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-35 OL-20002-02...
You should not save the running configuration of a router when it is configured for a graceful shutdown Note because the router will continue to advertise a maximum metric after it is reloaded. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-36 OL-20002-02...
At the interface level, you can also control the following timers: Retransmit interval—Sets the estimated time between successive LSAs. • Transmit delay—Sets the estimated time to transmit an LSA to a neighbor. • Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-37 OL-20002-02...
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Sets the LSA arrival time in milliseconds. The range is timers lsa-arrival msec from 10 to 600000. The default is 1000 milliseconds. Example: switch(config-router)# timers lsa-arrival 2000 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-38 OL-20002-02...
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(Optional) Displays information about OSPF. show ip ospf Example: switch(config-if)# show ip ospf Step 13 (Optional) Saves this configuration change. copy running-config startup-config Example: switch(config-if)# copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-39 OL-20002-02...
Ensure that you are in the correct VDC (or use the switchto vdc command). SUMMARY STEPS config t router ospf instance-tag graceful-restart graceful-restart grace-period seconds graceful-restart helper-disable graceful-restart planned-only show ip ospf instance-tag copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-40 OL-20002-02...
120 switch(config-router)# copy running-config startup-config Restarting an OSPFv2 Instance You can restart an OSPv2 instance. This clears all neighbors for the instance. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-41 OL-20002-02...
SPF minimum hold time 1000 milliseconds Additional References For additional information related to implementing OSPF, see the following sections: Related Documents, page 6-47 • MIBs, page 6-47 • Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-46 OL-20002-02...
Feature History for OSPFv2 Table 6-3 lists the release history for this feature. Table 6-3 Feature History for IOSPFv2 Feature Name Releases Feature Information OSPFv2 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 6-47 OL-20002-02...
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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 e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m . Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
Dijkstra’s Shortest Path First (SPF) algorithm to build its route table. You can divide OSPFv3 networks into areas. Routers send most LSAs only within one area, which reduces the CPU and memory requirements for an OSPF-enabled router. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
An OSPFv3 interface that receives these Hello packets determines if the settings are compatible with the receiving interface settings.Compatible interfaces are considered neighbors and are added to the neighbor table (see the “Neighbors” section on page 7-3). Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
(see the “Link-State Database” section on page 7-7). The local router compares these headers with its own link-state database and determines which LSAs are new or Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
Figure 7-1 DR in Multi-Access Network Router A Router B Router C Router D Router E or DR = Multi-access network = Logical connectivity to Designated Router for OSPF Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
For more information, see “Advanced Features” section on page 7-8. Link-State Advertisement OSPFv3 uses link-state advertisements (LSAs) to build its routing table. This section includes the following topics: Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
By default, the reference bandwidth is 40 Gb/s. The link cost is carried in the LSA updates for each link. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
MaxAge. Routers flood a repeat of the LSA every 30 minutes to prevent accurate link-state information from being aged out. Cisco NX-OS supports the LSA grouping feature to prevent all LSAs from refreshing at the same time. For more information, see the “Flooding and LSA Group Pacing”...
Use the address-family ipv6 unicast command to enter the IPv6 unicast address family configuration mode when configuring these features. Advanced Features Cisco NX-OS supports a number of advanced OSPFv3 features that enhance the usability and scalability of OSPFv3 in the network. This section includes the following topics: Stub Area, page 7-9 •...
With NSSA, you can extend OSPFv3 to cover the remote connection by defining the area between the corporate router and remote router as an NSSA (see the “Configuring NSSA” section on page 7-23). The backbone Area 0 cannot be an NSSA. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
Route summarization simplifies route tables by replacing more-specific addresses with an address that represents all the specific addresses. For example, you can replace 2010:11:22:0:1000::1 and 2010:11:22:0:2000:679:1 with one summary address, 2010:11:22::/32. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-10 OL-20002-02...
Summarizing overlapping ranges from two different routers could cause packets to be sent to the wrong destination. Configure external route summarization on ASBRs that are redistributing routes into OSPF When you configure a summary address, Cisco NX-OS automatically configures a discard route for the summary address to prevent routing black holes and route loops.
OSPFv3 supports Virtual Routing and Forwarding instances (VRFs). VRFs exist within virtual device contexts (VDCs). By default, Cisco NX-OS places you in the default VDC and default VRF unless you specifically configure another VDC and VRF. Each OSPFv3 instance can support multiple VRFs, up to the system limit.
(config-router)# timers throttle spf 1 50 50 switch (config-router)# timers lsa-arrival 10 Note 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. Configuring Basic OSPFv3 Configure OSPFv3 after you have designed your OSPFv3 network.
Maximum paths—Sets the maximum number of equal paths that OSPFv3 installs in the route table for a particular destination. Use this parameter for load balancing between multiple paths. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-14...
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(Optional) Configures the OSPFv3 router ID. This ID router-id id uses the dotted decimal notation and identifies this Example: OSPFv3 instance and must exist on a configured switch(config-router)# router-id interface in the system. 192.0.2.1 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-15 OL-20002-02...
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The range Example: is from 1 to 16. The default is 8. Used for load switch(config-router-af)# maximum-paths 4 balancing. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-16 OL-20002-02...
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MTU does not match the local interface MTU. Sets the OSPFv3 network type. ospfv3 network {broadcast | point-point} Example: switch(config-if)# ospfv3 network broadcast Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-18 OL-20002-02...
Ensure that there are no virtual links or ASBRs in the proposed stub area. Ensure that you are in the correct VDC (or use the switchto vdc command). SUMMARY STEPS config t router ospfv3 instance-tag Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-21 OL-20002-02...
You can create a totally stubby area and prevent all summary route updates from going into the stub area. To create a totally stubby area, use the following command in router configuration mode: Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-22...
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The following example shows how to create an NSSA that generates a default route; switch# config t switch(config)# router ospfv3 201 switch(config-router)# area 0.0.0.10 nssa default-info-originate switch(config-router)# copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-24 OL-20002-02...
Hello interval—Sets the time between successive Hello packets. • Retransmit interval—Sets the estimated time between successive LSAs. • Transmit delay—Sets the estimated time to transmit an LSA to a neighbor. • Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-26 OL-20002-02...
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Step 5 (Optional) Saves this configuration change. copy running-config startup-config Example: switch(config-router)# copy running-config startup-config You can configure the following optional commands in virtual link configuration mode: Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-27 OL-20002-02...
Default information originate ignores match statements in the optional route map. • Default metric—Sets all redistributed routes to the same cost metric. If you redistribute static routes, Cisco NX-OS also redistributes the default static route. Note Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
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| rip id | static} route-map map-name through the configured route map. Note If you redistribute static routes, Cisco NX-OS Example: switch(config-router-af)# redistribute also redistributes the default static route. bgp route-map FilterExternalBGP Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-29 OL-20002-02...
You can optionally configure the timeout period. BEFORE YOU BEGIN Ensure that you have enabled the OSPF feature (see the “Enabling the OSPFv3 Feature” section on page 7-13). Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-30 OL-20002-02...
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Optionally tries to retrieve the redistributed routes. The num-retries range is from 1 to 12. The timeout range is from 60 to 600 seconds. The default is 300 seconds. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-31 OL-20002-02...
SUMMARY STEPS config t router ospfv3 instance-tag address-family ipv6 unicast area area-id range ipv6-prefix/length [no-advertise] summary-address ipv6-prefix/length [no-advertise] [tag tag] show ipv6 ospfv3 summary-address copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-32 OL-20002-02...
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The following example shows how to create summary addresses on an ASBR: switch# config t switch(config)# router ospf 201 switch(config-router)# address-family ipv6 unicast switch(config-router)# summary-address 2001:0DB8::/48 switch(config-router)# copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-33 OL-20002-02...
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Sets the estimated time in seconds between LSAs ospfv3 retransmit-interval seconds transmitted from this interface. The range is from 1 to Example: 65535. The default is 5. switch(config-if)# ospfv3 retransmit-interval 30 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-35 OL-20002-02...
Ensure that you are in the correct VDC (or use the switchto vdc command). SUMMARY STEPS config t router ospfv3 instance-tag graceful-restart graceful-restart grace-period seconds graceful-restart helper-disable graceful-restart planned-only show ipv6 ospfv3 instance-tag copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-36 OL-20002-02...
120 switch(config-router)# copy running-config startup-config Restarting an OSPFv3 Instance You can restart an OSPv3 instance. This clears all neighbors for the instance. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-37 OL-20002-02...
OSPFv3 instance. show running-configuration ospfv3 Displays the current running OSPFv3 configuration. Displaying OSPFv3 Statistics To display OSPFv3 statistics, use the following commands: Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-40 OL-20002-02...
SPF calculation initial delay time 0 milliseconds Additional References For additional information related to implementing OSPF, see the following sections: Related Documents, page 7-43 • MIBs, page 7-43 • Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-42 OL-20002-02...
Feature History for OSPFv3 Table 7-3 lists the release history for this feature. Table 7-3 Feature History for IOSPFv3 Feature Name Releases Feature Information OSPFv3 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 7-43 OL-20002-02...
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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 e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m . Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
After this initial full route table update, EIGRP sends incremental updates to only those neighbors affected by the route change. This process speeds convergence and minimizes the bandwidth used by EIGRP. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
EIGRP also uses the Hello messages as a keepalive to its neighbors. As long as Hello messages are received, Cisco NX-OS can determine that a neighbor is alive and functioning. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
Delay—The sum of the delays configured on the interfaces that make up the route to the destination network. Configured in tens of microseconds. • Bandwidth—The calculation from the lowest configured bandwidth on an interface that is part of the route to the destination. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
Key-chain management allows you to control changes to the authentication keys used by MD5 authentication digest. See the Cisco Nexus 7000 Series NX-OS Security Configuration Guide, Release 4.x, for more details about creating key-chains.
Cisco NX-OS supports the Equal Cost Multiple Paths (ECMP) feature with up to 16 equal-cost paths in the EIGRP route table and the unicast RIB. You can configure EIGRP to load balance traffic across some or all of those paths.
If a Cisco NX-OS system experiences a cold reboot, network does not forward traffic to the system and removes the system from the network topology. In this scenario, EIGRP experiences a stateless restart, and all neighbors are removed.
Note You must enable graceful restart to support in-service software upgrades (ISSU) for EIGRP. If you disable graceful restart, Cisco NX-OS issues a warning that ISSU cannot be supported with this configuration. Licensing Requirements for EIGRP...
Autosummarization is not enabled by default. Cisco NX-OS supports only IP. • If you are familiar with the Cisco IOS CLI, be aware that the Cisco NX-OS commands for this feature Note might differ from the Cisco IOS commands that you would use.
1-5). Routes are not advertised or accepted from other autonomous systems unless you enable route redistribution. BEFORE YOU BEGIN Ensure that you have enabled the EIGRP feature (see the “Enabling the EIGRP Feature” section on page 8-9). Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 8-10 OL-20002-02...
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You can configure the time Example: between warning messages, from 1 to 65535, in switch(config-router)# seconds. The default is 10 seconds. This command is log-neighbor-warnings enabled by default. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 8-11 OL-20002-02...
You can restart an EIGRP instance. This clears all neighbors for the instance. To restart an EIGRP instance and remove all associated neighbors, use the following commands: Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 8-12 OL-20002-02...
{ip | ipv6} passive-interface eigrp instance-tag from forming and sending routing updates on an EIGRP interface. The instance tag can be any case-sensitive alphanumeric string up to 20 characters. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 8-13 OL-20002-02...
Ensure that all neighbors for an EIGRP process share the same authentication configuration, including the shared authentication key. Create the key-chain for this authentication configuration. See the Cisco NX-OS Security Configuration Guide. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
EIGRP will advertise the summary address out the interface with a metric equal to the minimum of all more specific routes. See the “Route Summarization” section on page 8-6. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 8-17 OL-20002-02...
{bgp id | direct | eigrp id | isis id | ospf id | rip id | static} route-map map-name redistribute maximum-prefix max [threshold] [warning-only | withdraw [num-retries timeout]] show running-config eigrp copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 8-20 OL-20002-02...
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The following example shows how to limit the number of redistributed routes into EIGRP: switch# config t switch(config)# router eigrp Test1 switch(config-router)# redistribute bgp route-map FilterExternalBGP switch(config-router)# redistribute maximum-prefix 1000 75 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 8-21 OL-20002-02...
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The following example shows how to configure graceful restart for EIGRP over IPv6 using the default timer values: switch# config t switch(config)# router eigrp Test1 switch(config-router)# address-family ipv6 unicast switch(config-router-af)# graceful-restart switch(config-router-af)# copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 8-24 OL-20002-02...
By default, split horizon is enabled on all interfaces. To disable split horizon, use the following command in interface configuration mode: Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 8-25 OL-20002-02...
Routes over this maximum are advertised as Example: unreachable. The range is from 1 to 255. The switch(config-router-af)# metric max-hops default is 100. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 8-26 OL-20002-02...
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{prefix-list name | route-map name} {in | and route map name can be any case-sensitive out} alphanumeric string up to 20 characters. Example: switch(config-if)# ip distribute-list eigrp Test1 route-map EigrpTest in Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 8-27 OL-20002-02...
The following example shows how to configure EIGRP: feature eigrp interface ethernet 1/2 ip address 192.0.2.55/24 ip router eigrp Test1 no shutdown router eigrp Test1 router-id 192.0.2.1 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 8-30 OL-20002-02...
NSF route-hold time NSF signal time Redistribution Disabled Split horizon Enabled Additional References For additional information related to implementing EIGRP, see the following sections: Related Documents, page 8-32 • Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 8-31 OL-20002-02...
EIGRP IPv6 support 4.1(2) Added support for IPv6. Authentication 4.0(3) Added the ability to configure authentication within a VRF for EIGRP. EIGRP 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 8-32 OL-20002-02...
IS-IS is an Interior Gateway Protocol (IGP) based on Standardization (ISO)/International Engineering Consortium (IEC) 10589. Cisco NX-OS supports Internet Protocol version 4 (IPv4). IS-IS is a dynamic link-state routing protocol that can detect changes in the network topology and calculate loop-free routes to other nodes in the network.
Level1/Level2 router that the Level 1 routers use as the default route to the Level 2 area. You can configure which Level1/Level2 router sets the attached bit. See the “Verifying IS-IS Configuration” section on page 9-28. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
S e 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 7 k - d o c f e e d b a c k @ c i s c o . c o m . Each IS-IS instance in Cisco NX-OS supports either a single Level 1 or Level 2 area, or one of each. By default, all IS-IS instances automatically support Level 1 and Level 2 routing.
In addition, IS-IS includes a sequence number in each packet to protect against replay attacks. You can use also keychains for hello and LSP authentication. See Cisco Nexus 7000 Series NX-OS Security Configuration Guide, Release 4.x for information on keychain management.
Cisco NX-OS issues a warning that ISSU cannot be supported with this configuration. Multiple IS-IS Instances Cisco NX-OS supports a maximum of four instances of the IS-IS protocol that run on the same node. You cannot configure multiple instances over the same interface. Every instance uses the same system router ID.
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• You can configure a maximum of four IS-IS instances per VDC. • Because the default reference bandwidth is different for Cisco NX-OS and Cisco IOS, the advertised tunnel IS-IS metric is different for these two operating systems. Configuring IS-IS...
Configuring Virtualization, page 9-23 • Tuning IS-IS, page 9-26 If you are familiar with the Cisco IOS CLI, be aware that the Cisco NX-OS commands for this feature Note might differ from the Cisco IOS commands that you would use.
Ensure that you have enabled the IS-IS feature (see the “Enabling the IS-IS Feature” section on page 9-7). Ensure that you are in the correct VDC (or use the switchto vdc command). Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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Use the no router isis command to remove the IS-IS instance and the associated configuration. Command Purpose Deletes the IS-IS instance and all associated no router isis instance-tag configuration. Example: switch(config)# no router isis Enterprise Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
You can restart an IS-IS instance. This clears all neighbors for the instance. To restart an IS-IS instance and remove all associated neighbors, use the following command: Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 9-10 OL-20002-02...
Ensure that you have enabled the IS-IS feature (see the “Enabling the IS-IS Feature” section on page 9-7). Ensure that you are in the correct VDC (or use the switchto vdc command). Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 9-14 OL-20002-02...
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The following example shows how to configure cleartext authentication on an IS-IS instance: switch# config t switch(config)# interface ethernet 1/2 switch(config-if)# isis authentication-type cleartext level-2 switch(config-if)# isis authentication key-chain ISISKey switch(config-if)# copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 9-15 OL-20002-02...
In addition to setting the overload bit, you might also want to suppress certain types of IP prefix advertisements from LSPs for Level 1 or Level 2 traffic. To set the overload bit, use the following command in router configuration mode: Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 9-16 OL-20002-02...
You can create aggregate addresses that are represented in the routing table by a summary address. One summary address can include multiple groups of addresses for a given level. Cisco NX-OS advertises the smallest metric of all the more-specific routes.
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[vrf vrf-name ] ip summary-address ip-prefix information. [longer-prefixes]] Example: switch(config-if)# show isis ip summary-address Step 6 (Optional) Saves this configuration change. copy running-config startup-config Example: switch(config--if)# copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 9-18 OL-20002-02...
Route redistribution can add many routes to the IS-IS route table. You can configure a maximum limit to the number of routes accepted from external protocols. IS-IS provides the following options to configure redistributed route limits: Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 9-20 OL-20002-02...
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{bgp id | direct | eigrp id | isis id | ospf id | rip id | static} the configured route map. route-map map-name Example: switch(config-router)# redistribute bgp route-map FilterExternalBGP Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 9-21 OL-20002-02...
Create the VDCs and VRFs. Ensure that you are in the correct VDC (or use the switchto vdc command). SUMMARY STEPS config t router isis instance-tag graceful-restart graceful-restart t3 manual time Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 9-22 OL-20002-02...
Configure all other parameters for an interface after you configure the VRF for an interface. Configuring Note a VRF for an interface deletes all the configuration for that interface. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 9-23 OL-20002-02...
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Exits VRF configuration mode. exit Example: switch(config-vrf)# exit switch(config)# Step 4 Creates a new IS-IS instance with the configured router isis instance-tag instance tag. Example: switch(config)# router isis Enterprise switch(config-router)# Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 9-24 OL-20002-02...
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[ interface-type slot/port ] in a VRF. Example: switch(config-if)# show isis Enterprise ethernet 1/2 Step 13 (Optional) Saves this configuration change. copy running-config startup-config Example: switch(config-if)# copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 9-25 OL-20002-02...
Enables IS-IS to generate and accept both narrow metric-style transition metric-style Type Length Value (TLV) objects and Example: wide metric-style TLV objects. The default is switch(config-router)# metric-style disabled. transition Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 9-26 OL-20002-02...
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Sets the interval in milliseconds between LSPs sent isis lsp-interval milliseconds on this interface during flooding. The range is from Example: 10 to 65535. The default is 33. switch(config-if)# isis lsp-interval 20 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 9-27 OL-20002-02...
[detail] Displays the technical support details for IS-IS. For detailed information about the fields in the output from these commands, see the Cisco NX-OS Command Reference. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
[instance-tag] traffic [* | interface] [vrf Clears the IS-IS traffic statistics. vrf-name] IS-IS Example Configuration The following example shows how to configure IS-IS: router isis Enterprise Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 9-29 OL-20002-02...
Metric Reference bandwidth 40 Gbps Additional References For additional information related to implementing IS-IS, see the following sections: Related Documents, page 9-31 • Standards, page 9-31 • Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 9-30 OL-20002-02...
Added support to set or unset the hello padding mode. Attached bit 4.1(2) Added support to set or unset the attached bit. IS-IS 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 9-31 OL-20002-02...
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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 e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m . Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
S e 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 7 k - d o c f e e d b a c k @ c i s c o . c o m . C H A P T E R Configuring Basic BGP This chapter describes how to configure Border Gateway Protocol (BGP) on a Cisco NX-OS device. This chapter includes the following sections: Information About Basic BGP, page 10-1 •...
BGP (iBGP) peering sessions. 4-Byte AS Number Support BGP supports 2-byte or 4-byte AS numbers. Cisco NX-OS displays 4-byte AS numbers in plain-text notation (that is, as 32-bit integers). You can configure 4-byte AS numbers as either plain-text notation (for example, 1 to 4294967295), or AS.dot notation (for example, 1.0).
Dynamis AS Numbers for Prefix Peers Cisco NX-OS accepts a range or list of AS numbers to establish BGP sessions. For example, if you configure BGP to use IPv4 prefix 192.0.2.0/8 and AS numbers 33, 66, and 99, BGP establishes a session with 192.0.2.1 with AS number 66 but rejects a session from 192.0.2.2 with AS number 50.)
A, B, and C. When Cisco NX-OS compares A and B, it chooses A. When Cisco NX-OS compares B and C, it chooses B. But when Cisco NX-OS compares A and C, it might not choose A because some BGP metrics apply only among paths from the same neighboring autonomous system and not among all paths.
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11-9 for more information. 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. If the paths have different IGP metrics to their next-hop addresses, then Cisco NX-OS chooses the path with the lower IGP metric.
If the path includes an originator attribute, then Cisco NX-OS uses that attribute as the router ID to compare to; otherwise, Cisco NX-OS uses the router ID of the peer that sent the path. If the paths have different router IDs, Cisco NX-OS chooses the path with the lower router ID.
BGP supports Virtual Routing and Forwarding instances (VRFs). VRFs exist within virtual device contexts (VDCs). By default, Cisco NX-OS places you in the default VDC and default VRF unless you specifically configure another VDC and VRF. For more information, see the Cisco Nexus 7000 Series NX-OS Virtual Device Context Configuration Guide, Release 4.x and...
For more information, see Chapter 11, “Configuring Advanced BGP.” The following example shows how to enter router configuration mode: switch# configuration switch(config)# router bgp 64496 switch(config-router)# Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 10-8 OL-20002-02...
Neighbor Configuration Mode Cisco NX-OS provides the neighbor configuration mode to configure BGP peers. You can use neighbor configuration mode to configure all parameters for a peer. The following example shows how to enter neighbor configuration mode: switch(config)# router bgp 64496 switch(config-router)# neighbor 192.0.2.1...
Configuring Dynamic AS Numbers for Prefix Peers, page 10-16 • Clearing BGP Information, page 10-18 If you are familiar with the Cisco IOS CLI, be aware that the Cisco NX-OS commands for this feature Note might differ from the Cisco IOS commands that you would use.
Ensure that you have enabled the BGP feature (see the “Enabling the BGP Feature” section on page 10-10). BGP must be able to obtain a router ID (for example, a configured loopback address). Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 10-11 OL-20002-02...
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192.0.2.0 For exterior protocols, the network command controls which networks are advertised. Interior protocols use the network command to determine where to send updates. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 10-12 OL-20002-02...
You can shut down the BGP protoco and gracefully disable BGP and retains the configuration. To shut down BGP, use the following command in router configuration mode: Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 10-13 OL-20002-02...
32-bit integer in the form of a higher 16-bit switch(config)# router bgp 64496 decimal number and a lower 16-bit decimal numbe in switch(config-router)# xx.xx format. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 10-16 OL-20002-02...
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192.0.2.0/8 remote-as route-map BGPPeers switch(config-router-neighbor)# description Peer Router B switch(config-router-neighbor)# address-family ipv4 unicast switch(config-router-neighbor-af)# copy running-config startup-config Chapter 16, “Configuring Route Policy Manager.” for information on route maps. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 10-17 OL-20002-02...
{ip | ipv6} {unicast | multicast} Clears route flap statistics in the selected address flap-statistics [vrf vrf-name] family. The vrf-name can be any case-sensitive alphanumeric string up to 64 characters. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 10-18 OL-20002-02...
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All neighbors in that • VRF are cleared. The name can be any case-sensitive alphanumeric string up to 64 characters. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 10-19 OL-20002-02...
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All neighbors in that • VRF are cleared. The name can be any case-sensitive alphanumeric string up to 64 characters. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 10-20 OL-20002-02...
{ip | ipv6} {unicast | multicast} Displays the BGP routes that match a BGP [ip-address | ipv6-prefix] extcommunity-list extended community list. list-name [exact-match]} [vrf vrf-name] Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 10-21 OL-20002-02...
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Displays the information about BGP peer templates. Use the clear bgp peer-template command to clear all neighbors in a peer template. show bgp process Displays the BGP process information. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 10-22 OL-20002-02...
Always disabled Additional References For additional information related to implementing BGP, see the following sections: Related Documents, page 10-25 • • RFCs, page 10-25 • MIBs, page 10-25 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 10-24 OL-20002-02...
BGP table. Dynamic AS number for prefix peers 4.1(2) Added support for a range of AS numbers for BGP prefix peer configuration. 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 10-25 OL-20002-02...
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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 e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m . Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
BGP is an interdomain routing protocol that provides loop-free routing between organizations or autonomous systems. Cisco NX-OS supports BGP version 4. BGP version 4 includes multiprotocol extensions that allow BGP to carry routing information for IP multicast routes and multiple Layer 3 protocol address families.
A peer-policy template can inherit from a set of peer-policy templates. Cisco NX-OS evaluates these peer-policy templates in the order specified by the preference value in the inherit configuration. The lowest number is preferred over higher numbers.
If you change the inbound route policy, Cisco NX-OS passes these stored routes through the modified inbound route policy to update the route table without tearing down existing peering sessions. Soft reconfiguration inbound can use significant memory resources to store the unfiltered BGP routes.
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Each subautonomous system is fully meshed within itself and has a few connections to other subautonomous systems in the same confederation. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-4...
11-3, router B is the route reflector. When the route reflector receives routes advertised from router A, it advertises (reflects) the routes to routers C and D. Router A no longer has to advertise to both routers C and D. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-5 OL-20002-02...
Capabilities negotiation allows BGP to use only the set of features supported by both BGP peers on a link. If a BGP peer does not support capabilities negotiation, Cisco NX-OS will attempt a new session to the peer without capabilities negotiation if you have configured the address family as IPv4. Any other multiprotocol configuration (such as IPv6) requires capabilities negotiation.
BGP sets the administrative distance of the summary discard to 220 and sets the route type to discard. BGP does not use discard routes for next-hop resolution. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-7...
Non-critical events are related to next hops being added without affecting the best path or changing • the IGP metric to a single next hop. See the “Configuring BGP Next-Hop Address Tracking” section on page 11-23 for more information. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-8 OL-20002-02...
MED attribute and the router ID. Multiprotocol BGP BGP on Cisco NX-OS supports multiple address families. Multiprotocol BGP (MP-BGP) carries different sets of routes depending on the address family. For example, BGP can carry one set of routes for IPv4 unicast routing, one set of routes for IPv4 multicast routing, and one set of routes for IPv6 multicast routing.
If a Cisco NX-OS router experiences a cold reboot, the network does not forward traffic to the router and removes the router from the network topology. In this scenario, BGP experiences a nongraceful restart and removes all routes.
• Keepalive and hold timers must not be smaller than their default values If either of these requirements is not met, Cisco NX-OS issues a warning. You can proceed with the upgrade or downgrade, but service might be disrupted. Note Cisco NX-OS cannot guarantee ISSU for non-default timer values if the negotiated hold time between BGP peers is less than the system switchover time.
License Requirement Cisco NX-OS BGP requires an Enterprise Services license. For a complete explanation of the NX-OS licensing scheme and how to obtain and apply licenses, see the Cisco NX-OS Licensing Guide Prerequisites for BGP BGP has the following prerequisites: You must enable the BGP feature (see the “Enabling the BGP Feature”...
Configuring a Graceful Restart, page 11-39 Configuring Virtualization, page 11-40 • If you are familiar with the Cisco IOS CLI, be aware that the Cisco NX-OS commands for this feature Note might differ from the Cisco IOS commands that you would use.
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Step 2 Enables BGP and assigns the autonomous system router bgp autonomous-system-number number to the local BGP speaker. Example: switch(config)# router bgp 65536 switch(config-router)# Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-14 OL-20002-02...
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Use the show bgp neighbor command to see the template applied. See the Cisco Nexus 7000 Series NX-OS Unicast Routing Command Reference for details on all commands available in the template. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
Cisco NX-OS evaluates multiple peer policies for an address family using the preference value. The lowest preference value is evaluated first. Any attributes configured for the neighbor take priority over any attributes inherited by that neighbor from a BGP template.
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Applies a peer-policy template to the peer address inherit peer-policy template-name preference family configuration and assigns the preference value for this peer policy. Example: switch(config-router-neighbor-af)# inherit peer-policy BasePolicy 1 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-17 OL-20002-02...
Use the show bgp neighbor command to see the template applied. See the Cisco Nexus 7000 Series NX-OS Unicast Routing Command Reference for details on all commands available in the template. This example shows how to configure a BGP peer-session template and apply it to a BGP peer:...
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(Optional) Applies a peer template to the neighbor inherit peer template-name address family configuration. Example: switch(config-router-neighbor-af)# inherit peer BasePolicy Step 7 Exits BGP neighbor address family configuration exit mode. Example: switch(config-router-neighbor-af)# exit switch(config-router-neighbor)# Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-19 OL-20002-02...
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Use the show bgp neighbor command to see the template applied. See the Cisco Nexus 7000 Series NX-OS Unicast Routing Command Reference for details on all commands available in the template. This example shows how to configure a BGP peer template and apply it to a BGP peer:...
When a BGP peer that is part of a prefix peering disconnects, Cisco NX-OS holds its peer structures for a defined prefix peer timeout value. An established peer can reset and reconnect without danger of being blocked because other peers have consumed all slots for that prefix peering.
If you modify a route policy for BGP, you must reset the associated BGP peer sessions. If the BGP peers do not support route refresh, you can configure a soft reconfiguration for inbound policy changes. Cisco NX-OS automatically attempts a soft reset for the session.
BGP marks all next hops that are rejected by the route policy as invalid and does not calculate the best path for the routes that use the invalid next-hop address. To configure BGP next-hop filtering, use the following command in address-family configuration mode: Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-23 OL-20002-02...
Disables checking whether or not a single-hop disable-connected-check eBGP peer is directly connected. You must Example: manually reset the BGP sessions after using this switch(config-router-neighbor)# command. disable-connected-check Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-24 OL-20002-02...
5 Disabling a Fast External Fallover By default, the Cisco Nexus 7000 Series device supports fast external fallover for for neighbors in all VRFs and address-families (IPv4 or IPv6). Typically, when a BGP router loses connectivity to a directly connected eBGP peer, BGP triggers a fast external fallover by resetting the eBGP session to the peer.
1 to 20000. • switch(config-router-af)# dampening route-map bgpDamp suppress-limit—The range is from 1 to 20000. • max-suppress-time—The range is from 1 to • 255. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-28 OL-20002-02...
Enables dynamic capability. This command dynamic-capability triggers an automatic notification and session reset Example: for the BGP neighbor sessions. switch(config-router-neighbor)# dynamic-capability This command is disabled by default. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-29 OL-20002-02...
Ensure that you have enabled the BGP feature (see the “Enabling the BGP Feature” section on page 10-10). Ensure that you are in the correct VDC (or use the switchto vdc command). SUMMARY STEPS config t Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-30 OL-20002-02...
You can configure BGP to accept routing information from another routing protocol and redistribute that information through the BGP network. Optionally, you can assign a default route for redistributed routes. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-32...
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(Optional) Generates a default route into BGP. default-metric value Example: switch(config-router-af)# default-metric Step 6 (Optional) Saves this configuration change. copy running-config startup-config Example: switch(config-router-af)# copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-33 OL-20002-02...
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This example shows how to redistribute EIGRP into BGP: switch# config t switch(config)# router bgp 65536 switch(config-router)# address-family ipv4 unicast switch(config-router-af)# redistribute eigrp 201 route-map Eigrpmap switch(config-router-af)# copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-34 OL-20002-02...
AS number listed in the AS_path attribute for Example: eBGP. switch(config-router)# enforce-first-as Generates a system message when a neighbor log-neighbor-changes changes state. Example: switch(config-router)# log-neighbor-changes Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-36 OL-20002-02...
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To tune BGP, use the following optional commands in neighbor configuration mode: Command Purpose Sets a descriptive string for this BGP peer. The description string string can be up to 80 alphanumeric characters. Example: switch(config-router-neighbor)# description main site Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-37 OL-20002-02...
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{in | out} or outbound route updates. This command triggers Example: an automatic soft clear or refresh of BGP neighbor switch(config-router-neighbor-af)# sessions. prefix-list PrefixFilter in Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-38 OL-20002-02...
Example: switch# config t switch(config)# Step 2 router bgp as-number Creates a new BGP process with the configured autonomous system number. Example: switch(config)# router bgp 65536 switch(config-router)# Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-39 OL-20002-02...
Configuring Virtualization You can configure one BGP process in each VDC. You can create multiple VRFs within each VDC and use the same BGP process in each VRF. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-40 OL-20002-02...
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65536 switch(config-router)# Step 5 Enters the router VRF configuration mode and vrf vrf-name associates this BGP instance with a VRF. Example: switch(config-router)# vrf RemoteOfficeVRF switch(config-router-vrf)# Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-41 OL-20002-02...
{ip | ipv6} {unicast | multicast} Displays the BGP routes that match a BGP [ip-address | ipv6-prefix] extcommunity-list extended community list. list-name [exact-match]} [vrf vrf-name] Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-42 OL-20002-02...
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Displays the information about BGP peer templates. Use the clear bgp peer-template command to clear all neighbors in a peer template. show bgp process Displays the BGP process information. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-43 OL-20002-02...
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.shtml Feature History for BGP Table 11-2 lists the release history for this feature. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-45 OL-20002-02...
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BGP table. Dynamic AS number for prefix peers 4.1(2) Added support for a range of AS numbers for BGP prefix peer configuration. 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 11-46 OL-20002-02...
Key-chain management allows you to control changes to the authentication keys used by an MD5 authentication digest or simple text password authentication. See the Cisco Nexus 7000 Series NX-OS Security Configuration Guide, Release 4.x for more details about creating key-chains.
By default, split horizon is enabled on all interfaces. Route Filtering You can configure a route policy on a RIP-enabled interface to filter the RIP updates. Cisco NX-OS updates the route table with only those routes that the route policy allows.
Virtual Routing and Forwarding instances (VRFs). VRFs exist within virtual device contexts (VDCs). You can configure up to four RIP instances on a VDC. By default, Cisco NX-OS places you in the default VDC and default VRF unless you specifically configure another VDC and VRF. See the Cisco NX-OS Virtual Device Context Configuration Guide and Chapter 14, “Configuring Layer 3 Virtualization.”...
• • Tuning RIP, page 12-15 If you are familiar with the Cisco IOS CLI, be aware that the Cisco NX-OS commands for this feature Note might differ from the Cisco IOS commands that you would use. Enabling the RIP Feature You must enable the RIP feature before you can configure RIP.
Ensure that you are in the correct VDC (or use the switchto vdc command). SUMMARY STEPS config t router rip instance-tag address-family ip unicast show ip rip [instance instance-tag] [vrf vrf-name] copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 12-6 OL-20002-02...
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Configures the maximum number of equal-cost maximum-paths number Example: paths that RIP maintains in the route table. The switch(config-router-af)# maximum-paths 6 range is from 1 to 16. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 12-7 OL-20002-02...
“Enabling the RIP Feature” section on page 12-5). Ensure that you are in the correct VDC (or use the switchto vdc command). Configure a key chain if necessary before enabling authentication. See the Cisco NX-OS Security Configuration Guide for details on implementing key chains. SUMMARY STEPS config t Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
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. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 12-10 OL-20002-02...
Configuring Route Summarization You can create aggregate addresses that are represented in the routing table by a summary address. Cisco NX-OS advertises the summary address metric that is the smallest metric of all the more-specific routes.
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(Optional) Sets the default metric for all redistributed routes. The range is from 1 to 15. The default is 1. Example: switch(config-router-af)# distribute level-1 into level-2 all Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 12-12 OL-20002-02...
You can adjust these timers to tune routing protocol performance to better suit your internetwork needs. You must configure the same values for the RIP timers on all RIP-enabled routers in your network. Note Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 12-15 OL-20002-02...
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Specifies a route map to filter incoming or outgoing ip rip route-filter {prefix-list list-name | route-map map-name | [in | out] RIP updates. Example: switch(config-if)# ip rip route-filter route-map InputMap in Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 12-16 OL-20002-02...
[vrf vrf-name] Use the clear ip rip policy command to clear policy statistics. Use the clear ip rip statistics command to clear RIP statistics. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 12-17 OL-20002-02...
RIP feature Disabled Split horizon Enabled Additional References For additional information related to implementing RIP, see the following sections: Related Documents, page 12-19 • Standards, page 12-19 • Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 12-18 OL-20002-02...
Feature History for RIP Table 12-2 lists the release history for this feature. Table 12-2 Feature History for RIP Feature Name Releases Feature Information 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 12-19 OL-20002-02...
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(a default router to which all unroutable packets are sent). This section includes the following topics: Administrative Distance, page 13-2 • Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 13-1 OL-20002-02...
By default, a router prefers a static route to a dynamic route because a static route has a smaller Note administrative distance than a dynamic route. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 13-2 OL-20002-02...
License Requirement NX-OS Static routing 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 NX-OS...
S e 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 7 k - d o c f e e d b a c k @ c i s c o . c o m . If you are familiar with the Cisco IOS CLI, be aware that the Cisco NX-OS commands for this feature Note might differ from the Cisco IOS commands that you would use.
Displays the configured static routes. Static Routing Example Configuration This example shows how to configure static routing: config t ip route 192.0.2.0/8 192.0.2.10 copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 13-6 OL-20002-02...
Table 13-2 lists the release history for this feature. Table 13-2 Feature History for Static Routing Feature Name Releases Feature Information Static Routing 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 13-7 OL-20002-02...
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(VDCs). Each VDC acts as a standalone device with both Layer 2 and Layer 3 services available. You can configure up to 4 VDCs, including the default VDC. See the Cisco NX-OS Virtu- alization Configuration Guide for more information on VDCs.
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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 e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m . Cisco NX-OS further virtualizes each VDC to support virtual routing and forwarding instances (VRFs). You can configure multiple VRFs in a VDC.
Router C By default, Cisco NX-OS uses the VRF of the incoming interface to select which routing table to use for a route lookup. You can configure a route policy to modify this behavior and set the VRF that Cisco NX-OS uses for incoming packets.
VRRP—See Chapter 20, “Configuring VRRP” for more information. • XML—See the Cisco Nexus 7000 Series NX-OS XML Management Interface User Guide for more • information. See the appropriate configuration guide for each service for more information on configuring VRF support in that service.
For example, you can configure a syslog server to support a particular VRF. Figure 14-4 shows two syslog servers with each server supporting one VRF. syslog server A is configured in VRF Red, so Cisco NX-OS sends only system messages generated in VRF Red to syslog server A. Figure 14-4...
Setting the VRF Scope, page 14-12 Note 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. Creating a VRF You can create a VRF in a VDC.
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The following example shows how to create a VRF and add a static route to the VRF: switch# config t switch(config)# vrf context Enterprise switch(config-vrf)# ip route 192.0.2.0/8 192.0.2.10 switch(config-vrf)# exit switch(config)# copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 14-7 OL-20002-02...
Configures an IP address for this interface. You must ip address ip-prefix/length do this step after you assign this interface to a VRF. Example: switch(config-if)# ip address 192.0.2.1/16 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 14-8 OL-20002-02...
Ensure that you are in the correct VDC (or use the switchto vdc command). SUMMARY STEPS config t router protocol tag vrf vrf-name configure optional parameters for the protocol in the VRF. copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 14-9 OL-20002-02...
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Example: switch(config-if)# ip router ospf 201 area 0 Step 9 (Optional) Saves this configuration change. copy running-config startup-config Example: switch(config)# copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 14-10 OL-20002-02...
VRF that Cisco NX-OS uses to reach the service Use the filter-vrf keyword to filter information from the Example: selected VRF to this server. switch(config)# snmp-server host 192.0.2.1 use-vrf Red switch(config-vrf)# Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 14-11 OL-20002-02...
Default routing context is the default VRF. Example: switch# routing-context vrf red switch%red# To return to the default VRF scope, use the following command in EXEC mode: Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 14-12 OL-20002-02...
Lab vrf Red router ospf Production vrf Blue router-id 1.1.1.1 vrf Green router-id 2.2.2.2 !Configure one interface to use ospf Lab on VRF Red Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 14-13 OL-20002-02...
Related Topics The following topics can give more information on VRFs: Cisco Nexus 7000 Series NX-OS Fundamentals Configuration Guide, Release 4.x • Cisco Nexus 7000 Series NX-OS System Management Configuration Guide, Release 4.x • Default Settings Table 14-1 lists the default settings for VRF parameters.
Feature History for VRF Table 14-2 lists the release history for this feature. Table 14-2 Feature History for VRF Feature Name Releases Feature Information 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 14-15 OL-20002-02...
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• Feature History for Unicast RIB and FIB, page 15-14 Information About the Unicast RIB and FIB The unicast RIB (IPv4 RIB and IPv6 RIB) and FIB are part of the Cisco NX-OS forwarding architecture, as shown in Figure 15-1.
“Clearing Forwarding Information in the FIB” section on page 15-10. Dynamic TCAM Allocation Cisco NX-OS divides the FIB to support multiple address families. The FIB TCAM has 128K physical entries. Table 15-1 describes the default FIB TCAM allocation. Table 15-1...
The unicast RIB and FIB require 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 NX-OS licensing scheme, see the Cisco NX-OS Licensing Guide.
Clearing Routes in the Unicast RIB, page 15-13 • If you are familiar with the Cisco IOS CLI, be aware that the Cisco NX-OS commands for this feature Note might differ from the Cisco IOS commands that you would use.
Universal ID—Sets the random seed for the hash algorithm. You do not need to configure the • Universal ID. Cisco NX-OS chooses the Universal ID if you do not configure it. Note Load sharing uses the same path for all packets in a given flow. A flow is defined by the load-sharing method that you configure.
You can use per-packet load sharing to evenly distribute data traffic in an IP network over multiple equal-cost connections. Per-packet load sharing allows the router to send successive data packets over paths on a packet-by-packet basis rather than on a per-flow basis. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 15-6 OL-20002-02...
You configure per-packet load sharing on the input interface. This configuration determines the output interface that Cisco NX-OS chooses for the packet. For example, if you have ECMP paths on two output interfaces, Cisco NX-OS uses the following load-sharing methods for input packets on Ethernet 1/1: Per-packet load sharing if you configure per-packet load sharing on Ethernet 1/1.
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IP Adjacency Table for context default Total number of entries: 2 Address MAC Address Pref Source Interface Best 10.1.1.1 02:20:54 00e0.b06a.71eb mgmt0 10.1.1.253 00:06:27 0014.5e0b.81d1 mgmt0 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 15-8 OL-20002-02...
{ slot | all}] up to 64 characters. The slot range is from 1 to 10. Example: switch(config)# show forwarding inconsistency Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 15-9 OL-20002-02...
You can disable dynamic TCAM allocation only if the current TCAM usage is below the default Note allocation. See the “Returning the TCAM to Default Settings” section on page 15-11 for more information. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 15-10 OL-20002-02...
TCAM usage below the default allocation limits. Returning the TCAM to Default Settings You must return the TCAM to default settings before you can start a nondisruptive downgrade to Cisco NX-OS release earlier than Cisco NX-OS 4.2(1). If you attempt a nondisruptive downgrade, the downgrade may fail with the following error: TCAM allocation has changed.
1000 to 112000. The num-nexthops range is from 1 to 16. Example: switch# show routing memory estimate routes 5000 next-hops 16 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 15-12 OL-20002-02...
Displays the FIB distribution information. fib-state} show forwarding interfaces module slot Displays the FIB information for a module. show forwarding {ip | ipv4 | ipv6} route Displays routes in the FIB. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 15-13 OL-20002-02...
Added support to load balance per packet on an interface. Unicast RIB and FIB 4.0(3) Added support to clear individual routes in unicast RIB and FIB. Unicast RIB and FIB 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 15-14 OL-20002-02...
S e 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 7 k - d o c f e e d b a c k @ c i s c o . c o m . C H A P T E R Configuring Route Policy Manager This chapter describes how to configure the Route Policy Manager on the Cisco NX-OS device. This chapter includes the following sections: Information About Route Policy Manager, page 16-1 •...
IP packet. When Cisco NX-OS processes a route or packet through a route map, it compares the route or packet to each of the match statements configured. If the route or packet matches the configured criteria, Cisco NX-OS processes it based on the permit or deny configuration for that match entry in the route map and any set criteria configured.
Precedence • • You can use ACLs in a route map for policy-based routing only. See the Cisco Nexus 7000 Series NX-OS Security Configuration Guide, Release 4.x for more information on ACLs. AS Numbers for BGP You can configure a list of AS numbers to match against BGP peers. If a BGP peer matches an AS number in the list and matches the other BGP peer configuration, BGP creates a session.
A regular expression. • See the Cisco Nexus 7000 Series NX-OS Unicast Routing Command Reference for more information on regular expressions. Extended Community Lists for BGP Extended community lists support 4-byte AS numbers. You can configure community attributes in the...
Route Policy Manager 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 NX-OS licensing scheme, see the Cisco NX-OS Licensing Guide.
• Configuring Route Maps, page 16-11 • If you are familiar with the Cisco IOS CLI, be aware that the Cisco NX-OS commands for this feature Note might differ from the Cisco IOS commands that you would use. Configuring IP Prefix Lists IP prefix lists match the IP packet or route against a list of prefixes and prefix lengths.
65536:20 Creates an expanded BGP community list using a ip community-list expanded list-name {deny | permit} expression regular expression. Example: switch(config)# ip community-list expanded BGPComplex deny 50000:[0-9][0-9]_ Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 16-9 OL-20002-02...
Configuring a route map for BGP triggers an automatic soft clear or refresh of BGP neighbor sessions. SUMMARY STEPS config t route-map map-name [permit | deny] [seq] Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 16-11 OL-20002-02...
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You can configure the following optional match parameters for route maps in route-map configuration mode: The default-information originate command ignores match statements in the optional route Note map. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 16-12 OL-20002-02...
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Matches an IPv6 multicast packet based on the [[group ipgroup ] [ rp iprp ]] multicast source, group, or rendezvous point. Example: switch(config-route-map)# match ip multicast source 2001:0DB8::1 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 16-13 OL-20002-02...
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[ tagid... ] filtering or redistribution. Example: switch(config-route-map)# match tag 2 You can configure the following optional set parameters for route maps in route-map configuration mode: Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 16-14 OL-20002-02...
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Example: BGP route update. Use the ip extcommunity-list switch(config-route-map)# set extcomm-list command to create the extended community list. BGPextCommunity delete Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 16-15 OL-20002-02...
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255 (100 percent reliable). metric3—Loading. The range is from 1 to 200 • (100 percent loaded). metric4—MTU of the path. The range is from • 1 to 4294967295. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 16-16 OL-20002-02...
This example shows how to use an address family to configure Route Policy Manager so that any unicast and multicast routes from neighbor 209.0.2.1 are accepted if they match prefix-list AllowPrefix: router bgp 64496 neighbor 209.0.2.1 remote-as 64497 address-family ipv4 unicast Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 16-17 OL-20002-02...
Default Route Policy Manager Enabled Additional References For additional information related to implementing IP, see the following sections: Related Documents, page 16-19 • Standards, page 16-19 • Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 16-18 OL-20002-02...
Added support for generic specific extended community lists. Match AS numbers 4.1(2) Added support to match a range of AS numbers in a route map. Route Policy Manager 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 16-19 OL-20002-02...
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If the statement is marked as permit and the packets do not match any route map statements, the packets are sent back through the normal forwarding channels and destination-based routing is performed. See the “Route Maps” section on page 16-2. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 17-1 OL-20002-02...
You can optionally configure the set criteria for next-hop addresses to load balance traffic across Note up to 16 IP addresses. In this case, Cisco NX-OS sends all traffic for each IP flow to a particular IP next-hop address. List of default next-hop IP addresses—Route to the interface or the next-hop address specified by this set statement only if there is no explicit route for the destination address of the packet in the routing table.
NX-OS Policy-based routing requires an Enterprise Services license. For a complete explanation of the NX-OS licensing scheme and how to obtain and apply licenses, see the Cisco NX-OS Licensing Guide. Prerequisites for Policy-Based Routing Policy-Based Routing has the following prerequisites: Install the correct license.
S e 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 7 k - d o c f e e d b a c k @ c i s c o . c o m . If you are familiar with the Cisco IOS CLI, be aware that the Cisco NX-OS commands for this feature Note might differ from the Cisco IOS commands that you would use.
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192.0.2.2 Use the optional load-share keyword to load balance traffic across up to 16 next-hop addresses. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 17-6 OL-20002-02...
Example: switch(config-route-map)# set vrf MainVRF Cisco NX-OS routes the packet as soon as it finds a next hop and an interface. Verifying Policy-Based Routing Configuration To display policy-based routing configuration information, perform one of the following tasks:...
Parameters Default Policy-based routing disabled Additional References For additional information related to implementing IP, see the following sections: Related Documents, page 17-9 • • Standards, page 17-9 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 17-8 OL-20002-02...
Table 17-2 Feature History for Policy-Based Routing Feature Name Releases Feature Information IPv6 policies 4.2(1) Added support for IPv6 policies. policy-based routing 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 17-9 OL-20002-02...
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The AVG also answers Address Resolution Protocol (ARP) requests for the virtual IP address. Load sharing is achieved when the AVG replies to the ARP requests with different virtual MAC addresses. In Cisco NX-OS Release 4.1(2) and later, packets received on a routed port destined for the GLBP virtual Note IP address will terminate on the local router, regardless of whether that router is the active GLBP router or a redundant GLBP router.
0007.b400.0101 that points to router A. Client 2 shares the same default gateway IP address but receives the gateway MAC address 0007.b400.0102 because router B is sharing the traffic load with router A. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 18-3 OL-20002-02...
The authentication schemes differ on the router and in the incoming packet. MD5 digests differ on the router and in the incoming packet. • • Text authentication strings differ on the router and in the incoming packet. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 18-4 OL-20002-02...
License Requirement NX-OS GLBP 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 NX-OS licensing scheme, see the Cisco NX-OS Licensing Guide.
Enabling a GLBP Group, page 18-14 • Note 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. Enabling the GLBP Feature You must enable the GLBP feature before you can configure and enable any GLBP groups.
Configuring GLBP Authentication You can configure GLBP to authenticate the protocol using cleartext or an MD5 digest. MD5 authentication uses a key chain (see the Cisco Nexus 7000 Series NX-OS Security Configuration Guide, Release 4.x). BEFORE YOU BEGIN Ensure that you are in the correct VDC (or use the switchto vdc command).
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Example: switch(config-if-glbp)# copy running-config startup-config The following example shows how to configure MD5 authentication for GLBP on Ethernet 1/2 after creating the key chain: switch# config t Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 18-9 OL-20002-02...
AVG takes place. The seconds range is from 0 to 3600 seconds. The minimum delay default is 3600 seconds. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 18-13 OL-20002-02...
Configures the IPv4 address for the interface. ip ip-address /length Example: switch(config-if)# ip 192.0.2.1/8 Step 4 Creates a GLBP group and enters GLBP configuration glbp group-number mode. Example: switch(config-if)# glbp 1 switch(config-if-glbp)# Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 18-14 OL-20002-02...
[listen] [standby] brief selected state. GLBP Example Configuration The following example enables GLBP on an interface, with MD5 authentication, interface tracking, and weighted load balancing: Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 18-15 OL-20002-02...
Redirect timer 600 seconds Weighting Additional References For additional information related to implementing GLBP, see the following sections: Related Documents, page 18-17 • Standards, page 18-17 • Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 18-16 OL-20002-02...
Feature History for GLBP Feature Name Releases Feature Information Extended hold timers 4.2(1) Added support for extended hold timers for extended NSF support. GLBP 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 18-17 OL-20002-02...
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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 e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m . C H A P T E R Configuring HSRP This chapter describes how to configure the Hot Standby Router Protocol (HSRP) on the Cisco NX-OS device. This chapter includes the following sections: Information About HSRP, page 19-1 •...
HSRP. By sharing a virtual MAC address and a virtual IP address, two or more interfaces can act as a single virtual router. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 19-2 OL-20002-02...
From the host perspective, the virtual router remains the same. In Cisco NX-OS Release 4.1(2) and later, packets received on a routed port destined for the HSRP virtual Note IP address will terminate on the local router, regardless of whether that router is the active HSRP router or the standby HSRP router.
HSRP groups to load share traffic from the connected hosts while providing the default router redundancy expected from HSRP. Figure 19-2 shows an example of a load-sharing HSRP configuration. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 19-4 OL-20002-02...
HSRP interoperates with virtual port channels (vPCs). vPCs allow links that are physically connected to two different Cisco Nexus 7000 series devices to appear as a single port channel by a third device. See the Cisco Nexus 7000 Series NX-OS Layer 2 Switching Configuration Guide, Release 4.x for more information on vPCs.
License Requirement 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. For a complete explanation of the NX-OS licensing scheme, see the Cisco NX-OS Licensing Guide.
Configuring Extended Hold Timers for HSRP, page 19-16 • If you are familiar with the Cisco IOS CLI, be aware that the Cisco NX-OS commands for this feature Note might differ from the Cisco IOS commands that you would use.
“Enabling the HSRP Feature” section on page 19-8). Cisco NX-OS enables an HSRP group once you configure the virtual IP address on any member interface in the group. You should configure HSRP attributes such as authentication, timers, and priority before you enable the HSRP group.
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(Optional) Displays HSRP information. show hsrp [group group-number ] Example: switch(config-if)# show hsrp group 2 Step 9 (Optional) Saves this configuration change. copy running-config startup-config Example: switch(config-if)# copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 19-9 OL-20002-02...
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.
Authenticating HSRP You can configure HSRP to authenticate the protocol using cleartext or MD5 digest authentication. MD5 authentication uses a key chain (see the Cisco Nexus 7000 Series NX-OS Security Configuration Guide, Release 4.x). BEFORE YOU BEGIN Ensure that you have enabled the HSRP feature (see the “Enabling the HSRP Feature”...
HSRP interface for preemption. HSRP supports tracked objects and track lists. See Chapter 21, “Configuring Object Tracking” for more information on track lists. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 19-12 OL-20002-02...
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{ip | ipv6} route ip-prefix/length reachability configuration mode. The object-id range is from 1 to 500. Example: switch(config)# track 2 ip route 192.0.2.0/8 reachability switch(config-track# Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 19-13 OL-20002-02...
If you configure HSRP on a vPC-enabled interface, you can optionally configure the upper and lower threshold values to control when to fail over to the vPC trunk Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 19-14...
Specifies the IP redundancy name for an HSRP group. name string The string is from 1 to 255 characters. The default string Example: has the following format: switch(config-if-hsrp)# name HSRP-1 hsrp-<interface-short-name>-<group-id>. For example, hsrp-Eth2/1-1. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 19-15 OL-20002-02...
You must configure extended hold timers on all HSRP routers if you configure extended hold timers. If you configure a non-default hold timer, you should configure the same value on all HSRP routers when you configure HSRP extended hold timers. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 19-16 OL-20002-02...
Derived from HSRP group number Additional References For additional information related to implementing HSRP, see the following sections: Related Documents, page 19-19 • • MIBs, page 19-19 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 19-18 OL-20002-02...
Added support for extended hold timers for extended NSF support. CISCO-HSRP-MIB 4.2(1) Added support for CISCO-HSRP-MIB. Priority thresholds 4.1(3) Added support for vPC threshold values on HSRP priority. HSRP 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 19-19 OL-20002-02...
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Router Priority and Preemption” section. In Cisco NX-OS Release 4.1(2) and later, packets received on a routed port destined for the VRRP virtual Note IP address will terminate on the local router, regardless of whether that router is the master VRRP router or a backup VRRP router.
Router C as the new master, even though Router B has not failed. If you disable preemption, VRRP will only switch if the original master recovers or the new master fails. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 20-4...
VRRP interoperates with virtual port channels (vPCs). vPCs allow links that are physically connected to two different Cisco Nexus 7000 series devices to appear as a single port channel by a third device. See the Cisco Nexus 7000 Series NX-OS Layer 2 Switching Configuration Guide, Release 4.x for more information on vPCs.
License Requirement 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. For a complete explanation of the NX-OS licensing scheme, see the Cisco NX-OS Licensing Guide.
• Configuring VRRP Interface State Tracking, page 20-17 • If you are familiar with the Cisco IOS CLI, be aware that the Cisco NX-OS commands for this feature Note might differ from the Cisco IOS commands that you would use.
IP address because the VRRP master is only intended as a next-hop router to forward packets. Some applications require that Cisco NX-OS accept packets addressed to the virtual router IP. Use the secondary option to the virtual IP address to accept these packets when the local router is the VRRP master.
The default priority value for backups is 100. For devices whose interface IP address is the same as the primary virtual IP address (the master), the default value is 255. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 20-9...
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Ensure that you are in the correct VDC (or use the switchto vdc command). SUMMARY STEPS config t interface interface-type slot/port vrrp number shutdown priority level [forwarding-threshold lower lower-value upper upper-value] no shutdown show vrrp copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 20-10 OL-20002-02...
(Optional) Saves this configuration change. copy running-config startup-config Example: switch(config-if-vrrp)# copy running-config startup-config Configuring VRRP Authentication You can configure simple text authentication for a VRRP group. BEFORE YOU BEGIN Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 20-11 OL-20002-02...
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Ensure that you are in the correct VDC (or use the switchto vdc command). SUMMARY STEPS config t interface interface-type slot/port vrrp number shutdown authentication text password no shutdown show vrrp copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 20-12 OL-20002-02...
You can configure the time intervals for advertisement packets. BEFORE YOU BEGIN Ensure that you have enabled the VRRP feature (see the “Configuring VRRP” section on page 20-7). Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 20-13 OL-20002-02...
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Ensure that you are in the correct VDC (or use the switchto vdc command). SUMMARY STEPS config t interface interface-type slot/port vrrp number shutdown advertisement-interval seconds no shutdown show vrrp copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 20-14 OL-20002-02...
Preemption is enabled by default. BEFORE YOU BEGIN Ensure that you have enabled the VRRP feature (see the “Configuring VRRP” section on page 20-7). Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 20-15 OL-20002-02...
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Ensure that you are in the correct VDC (or use the switchto vdc command). SUMMARY STEPS config t interface interface-type slot/port vrrp number shutdown no preempt no shutdown show vrrp copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 20-16 OL-20002-02...
Interface state tracking changes the priority of the virtual router based on the state of another interface in the device. When the tracked interface goes down or the IP address is removed, Cisco NX-OS assigns the tracking priority value to the virtual router. When the tracked interface comes up and an IP address is configured on this interface, Cisco NX-OS restores the configured priority to the virtual router (see the“Configuring VRRP Priority”...
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Ensure that you are in the correct VDC (or use the switchto vdc command). SUMMARY STEPS config t interface interface-type slot/port vrrp number shutdown track interface type number priority value no shutdown show vrrp copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 20-18 OL-20002-02...
To verify VRRP configuration information, use the following commands: Command Purpose show vrrp Displays the VRRP status for all groups. show vrrp vr group-number Displays the VRRP status for a VRRP group. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 20-19 OL-20002-02...
Router A will become the master for this group first because it has a higher IP address (10.1.0.2). Advertising interval is the default 1 second. – Preemption is disabled. – Router A interface ethernet 1/0 ip address 10.1.0.2/16 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 20-20 OL-20002-02...
4.2(1) Added support for priority thresholds and vPC. VRRP object tracking 4.2(1) Added support for tracking multiple object types in VRRP. VRRP 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 20-22 OL-20002-02...
S e 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 7 k - d o c f e e d b a c k @ c i s c o . c o m . C H A P T E R Configuring Object Tracking This chapter describes how to configure object tracking on Cisco NX-OS devices. This chapter includes the following sections: Information About Object Tracking, page 21-1 •...
Other entities, such as virtual Port Channels (vPCs) can use an object track list to modify the state of a vPC based on the state of the multiple peer links that create the vPC. See the Cisco Nexus 7000 Series NX-OS Interfaces Configuration Guide, Release 4.x for more information on vPCs.
License Requirement NX-OS Object tracking 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 NX-OS licensing scheme, see the Cisco NX-OS Licensing Guide.
Configuring Object Tracking for a Nondefault VRF, page 21-12 Note 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.
Configuring Object Tracking for Route Reachability You can configure Cisco NX-OS to track the existence and reachability of an IP route. BEFORE YOU BEGIN Ensure that you are in the correct VDC (or use the switchto vdc command).
BEFORE YOU BEGIN Ensure that you are in the correct VDC (or use the switchto vdc command). Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 21-6 OL-20002-02...
Configures the threshold percent for the tracked list. threshold percentage up up-value down down-value The range from 0 to 100 percent. Example: switch(config-track)# threshold percentage up 70 down 30 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 21-8 OL-20002-02...
Ensure that you are in the correct VDC (or use the switchto vdc command). SUMMARY STEPS config t track track-number list threshold weight threshold weight up up-value down down-value object object-number weight value show track copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 21-9 OL-20002-02...
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In this example, the track list is up if object 10 and object 20 are up, and the track list goes to the down state if all three objects are down. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 21-10...
The tracked object or track list starts the delay timer when a state change occurs but does recognize a state change until the delay timer reaches zero. At that point, Cisco NX-OS checks the object state again and records a state change only if the object or list currently has a changed state.
20 down 30 Configuring Object Tracking for a Nondefault VRF You can configure Cisco NX-OS to track an object in a specific VRF. BEFORE YOU BEGIN Ensure that you are in the correct VDC (or use the switchto vdc command).
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This example shows how to modify tracked object 2 to use VRF Blue instead of VRF RED to look up reachability information for this object: switch# config t switch(config)# track 2 switch(config-track)# vrf member Blue switch(config-track)# copy running-config startup-config Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 21-13 OL-20002-02...
Default Tracked Object VRF Member of default VRF Additional References For additional information related to implementing object tracking, see the following sections: Related Documents, page 21-15 • Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 21-14 OL-20002-02...
Object track list 4.2(1) Added support for object track lists and Boolean expressions. IPv6 support 4.1(2) Added support for IPv6. Object tracking 4.0(1) This feature was introduced. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x 21-15 OL-20002-02...
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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 e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m . Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
S e 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 7 k - d o c f e e d b a c k @ c i s c o . c o m . A P P E N D I X IETF RFCs supported by Cisco NX-OS Unicast Features, Release 4.x This appendix lists the IETF RFCs supported in Cisco NX-OS Release 4.x. BGP RFCs RFCs Title...
RADIUS and IPv6 RFC 3513 Internet Protocol Version 6 (IPv6) Addressing Architecture RFC 3596 DNS Extensions to Support IP version 6 RFC 4193 Unique Local IPv6 Unicast Addresses Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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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 e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m . Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
Active virtual gateway. One virtual gateway within a GLBP group is elected as the active virtual gateway and is responsible for the operation of the protocol. See BDR. backup designated router Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x GL-1 OL-20002-02...
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All neighbors establish adjacency with only the designated router and the backup designated router. Diffusing Update Algorithm. EIGRP algorithm used to select optimal routes to a destination. DUAL Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x GL-2 OL-20002-02...
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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 e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m . External Border Gateway Protocol (BGP). Operates between external systems. eBGP Enhanced Interior Gateway Protocol. A Cisco routing protocol that uses the Diffusing Update EIGRP Algorithm to provide fast convergence and minimized bandwidth utilization.
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IS-IS A special message sent between routing peers to verify and maintain communications between the pair. keepalive A method of controlling authentication keys. See the Cisco NX-OS Security Configuration Guide. key-chain management An arbitrary number configured on an OSPF interface which is in shortest path first calculations.
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Sum of all link costs or the hop count that a packet experiences when routed from the source to the path length destination. The method of using route maps to alter the route selected for a packet. policy-based routing Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x GL-5 OL-20002-02...
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A router that has no direct connection to the main network and which routes to that network using a stub router known remote router. Switched Virtual Interface. Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x GL-6 OL-20002-02...
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A method of making a physical entity act as multiple, independent logical entities. virtualization Virtual Routing and Forwarding. A method used to create separate, independent Layer 3 entities within a system. Virtual Router Redundancy Protocol. VRRP Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x GL-7 OL-20002-02...
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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 e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m . Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...
S e 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 7 k - d o c f e e d b a c k @ c i s c o . c o m . Table 2-1 Cisco NX-OS Release 4.x Configuration Limits (continued) Feature Verified Limit Maximum Limit VRFs 200 per VDC VRRP 255 groups Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x OL-20002-02...
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Web Cache Communication Protocol. See WCCP example configuration 14-12 VRRP benefits 20-3 clearing statistics 20-20 configuring time intervals for advertisement packets 20-13 default settings 20-21 description 20-1 to 20-6 Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x IN-13 OL-20002-02...
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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 e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m . Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x...