Cisco IOS XR Routing Configuration Guide Cisco IOS XR Software Release 3.2 Corporate Headquarters Cisco Systems, Inc. 170 West Tasman Drive San Jose, CA 95134-1706 USA http://www.cisco.
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C O N T E N T S Preface xi Document Revision History xi Obtaining Documentation xii Cisco.
Contents How to Implement BGP on Cisco IOS XR Software RC-27 Enabling BGP Routing RC-28 Configuring a Routing Domain Confederation for BGP RC-31 Resetting eBGP Session Immediately Upon Link Failure RC-33 Logging Neighbor Changes RC-34 Adjusting BGP Timers RC-34 Changing the BGP Default Local Preference Value RC-35 Configuring the MED Metric for BGP RC-36 Configuring BGP Weights RC-38 Tuning the BGP Best Path Calculation RC-39 Indicating BGP Backdoor Routes RC-41 Configuring Aggregate Addresses RC-43 Redist
Contents Related Documents RC-80 Standards RC-80 MIBs RC-80 RFCs RC-80 Technical Assistance RC-81 Implementing IS-IS on Cisco IOS XR Software Contents RC-83 RC-83 Prerequisites for Implementing IS-IS on Cisco IOS XR Software Restrictions for Implementing IS-IS on Cisco IOS XR Software RC-84 RC-84 Information About Implementing IS-IS on Cisco IOS XR Software RC-84 IS-IS Functional Overview RC-85 Key Features Supported in the Cisco IOS XR IS-IS Implementation RC-85 IS-IS Configuration Grouping RC-85 IS-
Contents Customizing Routes for IS-IS RC-119 Configuration Examples for Implementing IS-IS on Cisco IOS XR Software RC-122 Configuring Single-Topology IS-IS for IPv6: Example RC-122 Configuring Multitopology IS-IS for IPv6: Example RC-123 Redistributing IS-IS Routes Between Multiple Instances: Example RC-123 Where to Go Next RC-124 Additional References RC-124 Related Documents RC-124 Standards RC-124 MIBs RC-124 RFCs RC-125 Technical Assistance RC-125 Implementing OSPF on Cisco IOS XR Software Content
Contents Enabling OSPF RC-145 Configuring Stub and Not-so-Stubby Area Types RC-147 Configuring Neighbors for Nonbroadcast Networks RC-150 Configuring Authentication at Different Hierarchical Levels for OSPF Version 2 RC-155 Controlling the Frequency that the Same LSA Is Originated or Accepted for OSPF RC-158 Creating a Virtual Link with MD5 Authentication to Area 0 for OSPF RC-160 Summarizing Subnetwork LSAs on an OSPF ABR RC-164 Redistributing Routes from One IGP into OSPF RC-166 Configuring OSPF Shortest
Contents RIB Support for IPv4 and IPv6 RC-197 How to Deploy and Monitor RIB RC-198 Verifying RIB Configuration Using the Routing Table RC-198 Verifying Networking and Routing Problems RC-198 Configuration Examples for RIB Monitoring RC-200 Output of show route Command: Example RC-200 Output of show route backup Command: Example RC-201 Output of show route best-local Command: Example RC-201 Output of show route connected Command: Example RC-201 Output of show route local Command: Example RC-201 Output of
Contents Simple Inbound Policy: Example RC-242 Modular Inbound Policy: Example RC-243 Translating Cisco IOS Route Maps to Cisco IOS XR Routing Policy Language: Example RC-244 Additional References RC-244 Related Documents RC-244 Standards RC-244 MIBs RC-245 RFCs RC-245 Technical Assistance RC-245 Implementing Static Routes on Cisco IOS XR Software Contents RC-247 RC-247 Prerequisites for Implementing Static Routes on Cisco IOS XR Software Information About Implementing Static Routes on Cisco IOS XR So
Contents Cisco IOS XR Routing Configuration Guide RC-x
Preface This is the preface for the Cisco IOS XR Routing Configuration Guide. The preface contains the following sections: • Document Revision History, page xi • Obtaining Documentation, page xii • Documentation Feedback, page xiii • Cisco Product Security Overview, page xiii • Obtaining Technical Assistance, page xiv • Obtaining Additional Publications and Information, page xv Document Revision History The Document Revision History table records technical changes to this document.
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Preface Obtaining Additional Publications and Information • Cisco Press publishes a wide range of general networking, training and certification titles. Both new and experienced users will benefit from these publications. For current Cisco Press titles and other information, go to Cisco Press at this URL: http://www.ciscopress.com • Packet magazine is the Cisco Systems technical user magazine for maximizing Internet and networking investments.
Implementing BGP on Cisco IOS XR Software The Border Gateway Protocol (BGP) is an Exterior Gateway Protocol (EGP) that allows you to create loop-free interdomain routing between autonomous systems. An autonomous system is a set of routers under a single technical administration. Routers in an autonomous system can use multiple Interior Gateway Protocols (IGP) to exchange routing information inside the autonomous system and an EGP to route packets outside the autonomous system.
Implementing BGP on Cisco IOS XR Software Prerequisites for Implementing BGP on Cisco IOS XR Software Prerequisites for Implementing BGP on Cisco IOS XR Software To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software BGP Router Identifier For BGP sessions between neighbors to be established, BGP must be assigned a router ID. The router ID is sent to BGP peers in the OPEN message when a BGP session is established. BGP attempts to obtain a router ID in the following ways (in order of preference): Note • By means of the address configured using the bgp router-id command in router configuration mode.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software – 512K (524,288) prefixes for IPv4 unicast. – 128K (131,072) prefixes for IPv4 multicast. – 128K (131,072) prefixes for IPv6 unicast.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software Router Configuration Mode The following example shows how to enter router configuration mode: RP/0/RP0/CPU0:router# configuration RP/0/RP0/CPU0:router(config)# router bgp 140 RP/0/RP0/CPU0:router(config-bgp)# Global Address Family Configuration Mode The following example shows how to enter global address family configuration mode: RP/0/RP0/CPU0:router(config)# router bgp 140 RP/0/RP0/CPU0:router(config-bg
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software Router(config-bgp-nbr)# remote-as 1 Router(config-bgp-nbr)# address-family ipv4 unicast Router(config-bgp-nbr-af)# maximum-prefix 1000 Configuration Templates The af-group, session-group, and neighbor-group configuration commands provide template support for the neighbor configuration in Cisco IOS XR software: The af-group command is used to group address family-specific neighbor commands within an IPv4 o
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software • Commands entered at the session group level define address family-independent commands (the same commands as in the neighbor submode). • Commands entered at the address family group level define address family-dependent commands for a specified address family (the same commands as in the neighbor-address family configuration submode).
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software Update group: 0.1 eBGP neighbor with no inbound or outbound policy; defaults to 'drop' Route refresh request: received 0, sent 0 0 accepted prefixes Prefix advertised 0, suppressed 0, withdrawn 0, maximum limit 524288 Threshold for warning message 75% Connections established 0; dropped 0 Last reset 00:00:14, due to BGP neighbor initialized External BGP neighbor not directly connected. 2.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software RP/0/RP0/CPU0:router(config)# router bgp 150 RP/0/RP0/CPU0:router(config-bgp)# session-group AS_2 RP/0/RP0/CPU0:router(config-bgp-sngrp)# advertisement-interval 20 RP/0/RP0/CPU0:router(config-bgp-sngrp)# exit RP/0/RP0/CPU0:router(config-bgp)# neighbor-group AS_1 RP/0/RP0/CPU0:router(config-bgp-nbrgrp)# advertisement-interval 15 RP/0/RP0/CPU0:router(config-bgp-nbrgrp)# exit RP/0/RP0/CPU0:router(config-bgp)#
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software RP/0/RP0/CPU0:router# show bgp neighbors 192.168.2.2 BGP neighbor is 192.168.2.2, remote AS 1, local AS 140, external link Remote router ID 0.0.0.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software Last reset 00:00:25, due to BGP neighbor initialized External BGP neighbor not directly connected. The inheritance rules used when groups are inheriting configuration from other groups are the same as the rules given for neighbors inheriting from groups.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software The following example displays sample output from the show bgp neighbors command using the inheritance keyword. The example shows that the neighbor inherits session parameters from neighbor group GROUP_1, which in turn inherits from session group GROUP_2.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software The following example displays sample output from the show bgp af-group command using the configuration keyword. This example shows from where each configuration item was inherited. The default-originate command was configured directly on this address family group (indicated by [ ]).
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software RP/0/RP0/CPU0:router# show bgp session-group GROUP_1 configuration session-group GROUP_1 ebgp-multihop 2 [s:GROUP_2] update-source Loopback0 [] dmz-link-bandwidth [s:GROUP_2 s:GROUP_3] The following is sample output from the show bgp session-group command with the inheritance keyword showing that the GROUP_1 session group inherits session parameters from the GROUP_3 and GROUP_2 session groups: RP/0/RP0/CP
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software The following is sample output from the show bgp neighbor-group command with the configuration keyword. The configuration setting source is shown to the right of each command.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software Routing Policy Enforcement External BGP (eBGP) neighbors must have an inbound and outbound policy configured. If no policy is configured, no routes are accepted from the neighbor, nor are any routes advertised to it. This added security measure ensures that routes cannot accidentally be accepted or advertised in the case of a configuration omission error.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software BGP scan interval 60 secs BGP is operating in STANDALONE mode. Process Speaker RecvTblVer 1 bRIB/RIB 1 SendTblVer 1 Some configured eBGP neighbors do not have both inbound and outbound policies configured for IPv4 Multicast address family. These neighbors will default to sending and/or receiving no routes and are marked with ’!’ in the output below.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software Table Policy The table policy feature in BGP allows you to configure traffic index values on routes as they are installed in the global routing table. This feature is enabled using the table-policy command and supports the BGP policy accounting feature. BGP policy accounting uses traffic indices that are set on BGP routes to track various counters.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software The BGP best path algorithm implementation is in three parts: Note • Part 1—Compares two paths to determine which is better. • Part 2—Iterates over all paths and determines which order to compare the paths to select the overall best path. • Part 3—Determines whether the old and new best paths differ enough so that the new best path should be used.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software If the bgp bestpath med always command is configured, then the MED comparison is always performed, regardless of neighbor AS in the paths. Otherwise, MED comparison depends on the AS paths of the two paths being compared, as follows: a. If a path has no AS path or the AS path starts with an AS_SET, then the path is considered to be internal, and the MED is compared with other internal paths b.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software 2. The best path in each group is determined. Determining the best path is achieved by iterating through all paths in the group and keeping track of the best one seen so far. Each path is compared with the best-so-far, and if it is better, it becomes the new best-so-far and is compared with the next path in the group. 3.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software Multiprotocol BGP is useful when you want a link dedicated to multicast traffic, perhaps to limit which resources are used for which traffic. Multiprotocol BGP allows you to have a unicast routing topology different from a multicast routing topology providing more control over your network and resources.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software A multicast routing protocol, such as PIM, uses the multicast BGP database to perform Reverse Path Forwarding (RPF) lookups for multicast-capable sources. Thus, packets can be sent and accepted on the multicast topology but not on the unicast topology.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software Note No penalty is applied to a BGP peer reset when route dampening is enabled. Although the reset withdraws the route, no penalty is applied in this instance, even if route flap dampening is enabled. Minimizing Flapping The route dampening feature minimizes the flapping problem as follows. Suppose again that the route to network A flaps.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software Figure 3 Three Fully Meshed iBGP Speakers Fully meshed autonomous system Router C Routes Router A Routes advertised External BGP speaker Routes not advertised Router A Routes S4217 Router B With route reflectors, all iBGP speakers need not be fully meshed because there is a method to pass learned routes to neighbors.
Implementing BGP on Cisco IOS XR Software Information About Implementing BGP on Cisco IOS XR Software Figure 5 More Complex BGP Route Reflector Model Partially meshed autonomous system Nonclient Router G Route reflector Router A Routes advertised Nonclient Router F Router A External BGP speaker Nonclient Cluster S4218 Router E Router B Client Router C Client Router D Client Figure 5 illustrates a more complex route reflector scheme.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software cluster ID so that a route reflector can recognize updates from route reflectors in the same cluster. All route reflectors serving a cluster should be fully meshed and all of them should have identical sets of client and nonclient peers. By default, the clients of a route reflector are not required to be fully meshed and the routes from a client are reflected to other clients.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software • Tuning the BGP Best Path Calculation, page RC-39 (optional) • Indicating BGP Backdoor Routes, page RC-41 (optional) • Configuring Aggregate Addresses, page RC-43 (optional) • Redistributing iBGP Routes into IGP, page RC-44 (optional) • Redistributing Prefixes into Multiprotocol BGP, page RC-46 (optional) • Configuring BGP Route Dampening, page RC-48 (optional) • Applying Policy When Updating the Routing T
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Restrictions If the neighbor is configured as an external BGP (eBGP) peer, you must configure an inbound and outbound route policy on the neighbor using the route-policy command. SUMMARY STEPS 1. configure 2. route-policy name 3. end-policy 4. end or commit 5. configure 6. router bgp autonomous-system-number 7. bgp router-id {ip-address | interface-type interface-instance} 8. neighbor ip-address 9.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 3 Command or Action Purpose end-policy (Optional) Ends the definition of a route policy and exits route policy configuration mode. Example: RP/0/RP0/CPU0:router(config-rpl)# end-policy Step 4 Saves configuration changes.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 9 Command or Action Purpose remote-as autonomous-system-number Creates a neighbor and assigns it a remote autonomous system number of 2002. Example: RP/0/RP0/CPU0:router(config-bgp-nbr)# remote-as 2002 Step 10 address-family {ipv4 unicast | ipv4 multicast | ipv6 unicast | ipv6 multicast} Enters global address family configuration mode for the IPv4 address family.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software SUMMARY STEPS 1. configure 2. router bgp autonomous-system-number 3. bgp confederation identifier autonomous-system-number 4. bgp confederation peers autonomous-system-number 5. end or commit DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 4 Command or Action Purpose bgp confederation peers autonomous-system-number Specifies that the BGP autonomous systems 1091, 1092, 1093, 1094, 1095, and 1096 belong to BGP confederation identifier 5.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Logging Neighbor Changes Logging neighbor changes is enabled by default. Use the log neighbor changes disable command to turn off logging. The log neighbor changes disable command can also be used to turn logging back on if it has been disabled. Adjusting BGP Timers Perform this task to set the timers for BGP neighbors.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 4 Command or Action Purpose neighbor ip-address Places the router in neighbor configuration mode for BGP routing and configures the neighbor IP address 172.168.40.24 as a BGP peer. Example: RP/0/RP0/CPU0:router(config-bgp)# neighbor 172.168.40.24 Step 5 timers keepalive hold-time Example: (Optional) Sets the keepalive timer to 60 seconds and the hold-time timer to 220 seconds for BGP neighbor 172.168.40.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router bgp autonomous-system-number Enters BGP configuration mode allowing you to configure the BGP routing process.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software 4. end or commit DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router bgp autonomous-system-number Enters BGP configuration mode allowing you to configure the BGP routing process.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Configuring BGP Weights Perform this task to assign a weight to routes received from a neighbor. A weight is a number that you can assign to a path so that you can control the best path selection process. If you have particular neighbors that you want to prefer for most of your traffic, you can use the weight command to assign a higher weight to all routes learned from that neighbor.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 5 Command or Action Purpose address-family {ipv4 unicast | ipv4 multicast | ipv6 unicast | ipv6 multicast} Enters neighbor address family configuration mode for the IPv4 address family. Example: RP/0/RP0/CPU0:router(config-bgp-nbr)# address-family ipv4 unicast Step 6 weight weight-value Assigns a weight of 41150 to all IPv4 unicast routes learned through 172.168.40.24.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software 8. end or commit DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router bgp autonomous-system-number Enters BGP configuration mode allowing you to configure the BGP routing process.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 7 Command or Action Purpose bgp bestpath compare-routerid Configure the BGP speaker in autonomous system 120 to compare the router IDs of similar paths. Example: RP/0/RP0/CPU0:router(config-bgp)# bgp bestpath compare-routerid Step 8 Saves configuration changes.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router bgp autonomous-system-number Enters BGP configuration mode allowing you to configure the BGP routing process.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Configuring Aggregate Addresses Perform this task to create aggregate entries in a BGP routing table. SUMMARY STEPS 1. configure 2. router bgp autonomous-system-number 3. address-family {ipv4 unicast | ipv4 multicast | ipv6 unicast | ipv6 multicast} 4. aggregate-address address/mask-length [as-set] [as-confed-set] [summary-only] [route-policy route-policy-name] 5.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 4 Command or Action Purpose aggregate-address address/mask-length [as-set] [as-confed-set] [summary-only] [route-policy route-policy-name] Creates an aggregate address. The path advertised for this route is an autonomous system set consisting of all elements contained in all paths that are being summarized.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software SUMMARY STEPS 1. configure 2. router bgp autonomous-system-number 3. bgp redistribute-internal 4. end or commit DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router bgp autonomous-system-number Enters BGP configuration mode allowing you to configure the BGP routing process.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Redistributing Prefixes into Multiprotocol BGP Perform this task to redistribute prefixes from another protocol into multiprotocol BGP. Redistribution is the process of injecting prefixes from one routing protocol into another routing protocol. This task shows how to inject prefixes from another routing protocol into multiprotocol BGP.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 4 Command or Action Purpose redistribute connected [metric metric-value] [route-policy route-policy-name] Causes IPv4 unicast OSPF routes from OSPF instance 110 to be redistributed into BGP.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Configuring BGP Route Dampening Perform this task to configure and monitor BGP route dampening. SUMMARY STEPS 1. configure 2. router bgp autonomous-system-number 3. address-family {ipv4 unicast | ipv4 multicast | ipv6 unicast | ipv6 multicast} 4. bgp dampening [half-life [reuse suppress max-suppress-time] | route-policy route-policy-name] 5. end or commit 6.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router bgp autonomous-system-number Enters BGP configuration mode allowing you to configure the BGP routing process.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 6 Command or Action Purpose show bgp [ipv4 {unicast | multicast | all} | ipv6 {unicast | all} | all {unicast | multicast | all}] flap-statistics Displays BGP flap statistics for all paths.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 12 Command or Action Purpose clear bgp {ipv4 {unicast | multicast | all} | ipv6 {unicast | all} | all {unicast | multicast | all}} flap-statistics regexp regular-expression Clears BGP flap statistics for all paths that match the regular expression _1$.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Applying Policy When Updating the Routing Table Perform this task to apply a routing policy to routes being installed into the routing table. Prerequisites See the Implementing Routing Policy on Cisco IOS XR Software module of the Cisco IOS XR Routing Configuration Guide for a list of the supported attributes and operations that are valid for table policy filtering. SUMMARY STEPS 1. configure 2.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 4 Command or Action Purpose table-policy policy-name Applies the tbl-plcy-A policy to IPv4 unicast routes being installed into the routing table. Example: RP/0/RP0/CPU0:router(config-bgp-af)# table-policy tbl-plcy-A Step 5 Saves configuration changes.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router bgp autonomous-system-number Enters BGP configuration mode allowing you to configure the BGP routing process.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Configuring a BGP Neighbor Group Perform this task to configure BGP neighbor groups and apply the neighbor group configuration to a neighbor. After a neighbor group is configured, each neighbor can inherit the configuration through the use command.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router bgp autonomous-system-number Enters BGP configuration mode allowing you to configure the BGP routing process. Example: RP/0/RP0/CPU0:router(config)# router bgp 120 Step 3 neighbor-group name Places the router in neighbor group configuration mode.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 10 Command or Action Purpose password {clear | encrypted} password (Optional) Configures neighbor group nbr-grp-A to use MD5 authentication with the password pswd123. Example: RP/0/RP0/CPU0:router(config-bgp-nbrgrp)# password clear pswd123 Step 11 password-disable (Optional) Overrides any inherited password configuration from the neighbor group.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 19 Command or Action Purpose use neighbor-group group-name (Optional) Specifies that BGP neighbor 172.168.40.24 inherit configuration from neighbor group nbr-grp-A. Example: RP/0/RP0/CPU0:router(config-bgp-nbr)# use neighbor-group nbr-grp-A Step 20 Saves configuration changes.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router bgp autonomous-system-number Enters BGP configuration mode allowing you to configure the BGP routing process.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Configuring a Route Reflector for BGP Perform this task to configure a route reflector for BGP. All the neighbors configured with the route-reflector-client command are members of the client group, and the remaining iBGP peers are members of the nonclient group for the local route reflector. Together, a route reflector and its clients form a cluster. A cluster of clients usually has a single route reflector.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 4 Command or Action Purpose neighbor ip-address Places the router in neighbor configuration mode for BGP routing and configures the neighbor IP address 172.168.40.24 as a BGP peer. Example: RP/0/RP0/CPU0:router(config-bgp)# neighbor 172.168.40.24 Step 5 remote-as autonomous-system-number Creates a neighbor and assigns it a remote autonomous system number of 2002.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Configuring BGP Route Filtering by Route Policy Perform this task to configure BGP routing filtering by route policy. Prerequisites See the Implementing Routing Policy on Cisco IOS XR Software module of the Cisco IOS XR Routing Configuration Guide for a list of the supported attributes and operations that are valid for inbound and outbound neighbor policy filtering. SUMMARY STEPS 1. configure 2.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 4 Command or Action Purpose router bgp autonomous-system-number Enters BGP configuration mode allowing you to configure the BGP routing process. Example: RP/0/RP0/CPU0:router(config)# router bgp 120 Step 5 neighbor ip-address Example: Places the router in neighbor configuration mode for BGP routing and configures the neighbor IP address 172.168.40.24 as a BGP peer.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Disabling Next Hop Processing on BGP Updates Perform this task to disable next hop calculation for a neighbor and insert your own address in the next hop field of BGP updates. Disabling the calculation of the best next hop to use when advertising a route causes all routes to be advertised with the network device as the next hop.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 5 Command or Action Purpose address-family {ipv4 unicast | ipv4 multicast | ipv6 unicast | ipv6 multicast} Enters neighbor address family configuration mode for the IPv4 address family. Example: RP/0/RP0/CPU0:router(config-bgp-nbr)# address-family ipv4 unicast Step 6 RP/0/RP0/CPU0:router(config-bgp-nbr-af)# next-hop-self Sets the next hop attribute for all IPv4 unicast routes advertised to neighbor 172.168.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software SUMMARY STEPS 1. configure 2. router bgp autonomous-system-number 3. neighbor ip-address 4. remote-as autonomous-system-number 5. address-family {ipv4 unicast | ipv4 multicast | ipv6 unicast | ipv6 multicast} 6. send-community-ebgp 7. end or commit DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 6 Command or Action Purpose send-community-ebgp Specifies that the router send community attributes (which are disabled by default for eBGP neighbors) to eBGP neighbor 172.168.40.24 for IPv4 multicast routes. Example: RP/0/RP0/CPU0:router(config-bgp-nbr-af)# send-community-ebgp Step 7 Saves configuration changes.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software 4. address-family {ipv4 unicast | ipv4 multicast | ipv6 unicast | ipv6 multicast} 5. soft-reconfiguration inbound always 6. end or commit DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router bgp autonomous-system-number Enters BGP configuration mode allowing you to configure the BGP routing process.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 5 Command or Action Purpose soft-reconfiguration inbound always Configures the software to store updates received from neighbor 172.168.40.24. Soft reconfiguration inbound causes the software to store the original unmodified route in addition to a route that is modified or filtered. This allows a “soft clear” to be performed after the inbound policy is changed.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router bgp autonomous-system-number Enters BGP configuration mode allowing you to configure the BGP routing process.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Resetting Neighbors Using BGP Dynamic Inbound Soft Reset Perform this task to trigger an inbound soft reset of the specified address families for the specified group or neighbors. Resetting neighbors is useful if you change the inbound policy for the neighbors or any other configuration that affects the sending or receiving of routing updates.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software SUMMARY STEPS 1. show bgp neighbors 2. clear bgp {ipv4 | ipv6 | all} {unicast | multicast | all} {* | ip-address | as-number | external} soft out DETAILED STEPS Step 1 Command or Action Purpose show bgp neighbors Verifies that received route refresh capability from the neighbor is enabled.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Clearing Caches, Tables and Databases Perform this task to remove all contents of a particular cache, table, or database. Clearing a cache, table, or database can become necessary when the contents of the particular structure have become, or are suspected to be, invalid. SUMMARY STEPS 1. clear bgp ip-address 2. clear bgp external 3.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software 8. show bgp neighbor-group group-name configuration 9. show bgp summary DETAILED STEPS Step 1 Command or Action Purpose show bgp cidr-only Displays routes with nonnatural network masks (classless interdomain routing [CIDR]) routes. Example: RP/0/RP0/CPU0:router# show bgp cidr-only Step 2 show bgp count-only Displays the number of paths.
Implementing BGP on Cisco IOS XR Software How to Implement BGP on Cisco IOS XR Software Step 7 Command or Action Purpose show bgp paths Displays all BGP paths in the database. Example: RP/0/RP0/CPU0:router# show bgp paths Step 8 show bgp neighbor-group group-name configuration Displays the effective configuration for neighbor group group_1, including any configuration inherited by this neighbor group.
Implementing BGP on Cisco IOS XR Software Configuration Examples for Implementing BGP on Cisco IOS XR Software Configuration Examples for Implementing BGP on Cisco IOS XR Software This section provides the following configuration examples: • Enabling BGP: Example, page RC-76 • Displaying BGP Update Groups: Example, page RC-77 • BGP Neighbor Configuration: Example, page RC-78 • BGP Confederation: Example, page RC-78 • BGP Route Reflector: Example, page RC-79 Enabling BGP: Example The following sho
Implementing BGP on Cisco IOS XR Software Configuration Examples for Implementing BGP on Cisco IOS XR Software address-family ipv4 multicast aggregate-address 10.2.0.0/24 route-policy set_next_hop_agg_v4 aggregate-address 10.3.0.
Implementing BGP on Cisco IOS XR Software Configuration Examples for Implementing BGP on Cisco IOS XR Software BGP Neighbor Configuration: Example The following example shows how BGP neighbors on an autonomous system are configured to share information. In the example, a BGP router is assigned to autonomous system 109, and two networks are listed as originating in the autonomous system. Then the addresses of three remote routers (and their autonomous systems) are listed.
Implementing BGP on Cisco IOS XR Software Where to Go Next neighbor 199.99.99.2 remote-as 700 In a BGP speaker in autonomous system 6003, the peers from autonomous systems 6001 and 6002 are configured as special eBGP peers. Peer 200.200.200.200 is a normal eBGP peer from autonomous system 701. router bgp 6003 bgp confederation identifier 666 bgp confederation peers 6001 6002 neighbor 171.69.232.57 remote-as 6001 neighbor 171.69.232.55 remote-as 6002 neighbor 200.200.200.
Implementing BGP on Cisco IOS XR Software Additional References Additional References The following sections provide references related to implementing BGP for Cisco IOS XR software. Related Documents Related Topic Document Title BGP commands: complete command syntax, command Cisco IOS XR Routing Command Reference, Release 3.2 modes, command history, defaults, usage guidelines, and examples Standards Standards Title draft-ietf-idr-bgp4-26.txt A Border Gateway Protocol 4, by Y. Rekhter, T.Li, S.
Implementing BGP on Cisco IOS XR Software Additional References RFCs Title RFC 3065 Autonomous System Confederations for BGP RFC 3392 Capabilities Advertisement with BGP-4 Technical Assistance Description Link http://www.cisco.com/techsupport The Cisco Technical Support website contains thousands of pages of searchable technical content, including links to products, technologies, solutions, technical tips, and tools. Registered Cisco.com users can log in from this page to access even more content.
Implementing BGP on Cisco IOS XR Software Additional References Cisco IOS XR Routing Configuration Guide RC-82
Implementing IS-IS on Cisco IOS XR Software Integrated Intermediate System-to-Intermediate System (IS-IS), Internet Protocol Version 4 (IPv4), is a standards-based Interior Gateway Protocol (IGP). Cisco IOS XR implements the IP routing capabilities described in International Organization for Standardization (ISO)/International Engineering Consortium (IEC) 10589 and RFC 1995, and adds the standard extensions for single topology and multitopology IS-IS for IP Version 6 (IPv6).
Implementing IS-IS on Cisco IOS XR Software Prerequisites for Implementing IS-IS on Cisco IOS XR Software Prerequisites for Implementing IS-IS on Cisco IOS XR Software The following are prerequisites for implementing IS-IS on Cisco IOS XR software: • You must be in a user group associated with a task group that includes the proper task IDs for IS-IS commands. Task IDs for commands are listed in the Cisco IOS XR Task ID Reference Guide.
Implementing IS-IS on Cisco IOS XR Software Information About Implementing IS-IS on Cisco IOS XR Software IS-IS Functional Overview Small IS-IS networks are typically built as a single area that includes all routers in the network. As the network grows larger, it may be reorganized into a backbone area made up of the connected set of all Level 2 routers from all areas, which is in turn connected to local areas. Within a local area, routers know how to reach all system IDs.
Implementing IS-IS on Cisco IOS XR Software Information About Implementing IS-IS on Cisco IOS XR Software IS-IS Interfaces IS-IS interfaces can be configured as one of the following types: • active—advertises connected prefixes and forms adjacencies. This is the default for interfaces. • passive—advertises connected prefixes but does not form adjacencies. The passive command is used to configure interfaces as passive.
Implementing IS-IS on Cisco IOS XR Software Information About Implementing IS-IS on Cisco IOS XR Software Flood Blocking on Specific Interfaces With this technique, certain interfaces are blocked from being used for flooding LSPs, but the remaining interfaces operate normally for flooding. This technique is simple to understand and configure, but may be more difficult to maintain and more error prone than mesh groups in the long run.
Implementing IS-IS on Cisco IOS XR Software Information About Implementing IS-IS on Cisco IOS XR Software When single-topology support for IPv6 is used, only narrow link metrics, also known as old-style type, length, and value (TLV) arguments, may be employed. During single-topology operation, one shortest path first (SPF) computation for each level is used to compute both IPv4 and IPv6 routes.
Implementing IS-IS on Cisco IOS XR Software Information About Implementing IS-IS on Cisco IOS XR Software Note If you configure IETF NSF on the Cisco IOS XR router and a neighbor router does not support IETF NSF, the affected adjacencies flap, but nonstop forwarding is maintained to all neighbors that do support IETF NSF. A restart reverts to a cold start if no neighbors support IETF NSF. Multi-Instance IS-IS You may configure as many IS-IS instances as system resources (memory and interfaces) allow.
Implementing IS-IS on Cisco IOS XR Software Information About Implementing IS-IS on Cisco IOS XR Software Default Routes You can force a default route into an IS-IS routing domain. Whenever you specifically configure redistribution of routes into an IS-IS routing domain, the Cisco IOS XR software does not, by default, redistribute the default route into the IS-IS routing domain. The default-information originate command generates a default route into IS-IS, which can be controlled by a route map.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software This section contains the following procedures: Note • Enabling IS-IS and Configuring Level 1 or Level 2 Routing, page RC-91 (required) • Configuring Single Topology for IS-IS, page RC-93 (required) • Configuring Multitopology for IS-IS, page RC-98 (optional) • Controlling LSP Flooding for IS-IS, page RC-102 (optional) • Configuring Nonstop Forwarding for IS
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router isis instance-id Example: Enables IS-IS routing for the specified routing instance, and places the router in router configuration mode.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Step 5 Command or Action Purpose end Saves configuration changes.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software The default metric style for single topology is narrow metrics. However, you can use either wide metrics or narrow metrics. How to configure them depends on how single topology is configured. If both IPv4 and IPv6 are enabled and single topology is configured, the metric style is configured in the address-family ipv4 stanza.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 interface type number Enters interface configuration mode. Example: RP/0/RP0/CPU0:router(config)# interface POS 0/1/0/3 Step 3 ipv6 address ipv6-prefix/prefix-length [eui-64] Defines the IPv4 address for the interface.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Step 4 Command or Action Purpose exit Exits interface configuration mode, and returns the router to global configuration mode. Example: RP/0/RP0/CPU0:router(config-if)# exit Step 5 router isis instance-id Example: Enables IS-IS routing for the specified routing instance, and places the router in router configuration mode.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Step 11 Command or Action Purpose circuit-type {level-1 | level-1-2 | level-2-only} (Optional) Configures the type of adjacency. Example: RP/0/RP0/CPU0:router(config-isis-if)# circuit-type level-1-2 Step 12 address-family {ipv4 | ipv6} [unicast] Example: • The default circuit type is the configured system type (configured through the is-type command).
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Configuring Multitopology for IS-IS This task explains how to configure multitopology IS-IS. This task is optional. Multitopology is configured in much the same way as the single topology for IPv4 and IPv6 address families. The singletopology command is omitted, invoking the default multitopology behavior. SUMMARY STEPS 1. configure 2. interface type instance 3.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 interface type instance Enters interface configuration mode. Example: RP/0/RP0/CPU0:router(config)# interface POS 0/1/0/3 Step 3 ipv4 address address mask or Defines the IPv4 address for the interface.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Step 4 Command or Action Purpose exit Exits interface configuration mode, and returns the router to global configuration mode. Example: RP/0/RP0/CPU0:router(config-if)# exit Step 5 router isis instance-id Example: Enables IS-IS routing for the specified routing instance, and places the router in router configuration mode.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Step 11 Command or Action Purpose end Saves configuration changes.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Controlling LSP Flooding for IS-IS Flooding of LSPs can limit network scalability. You can control LSP flooding by tuning your LSP database parameters on the router globally or on the interface. This task is optional. Many of the commands to control LSP flooding contain an option to specify the level to which they apply. Without the option, the command applies to both levels.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 Enables IS-IS routing for the specified routing instance, and places the router in router configuration mode.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Step 8 Command or Action Purpose ignore-lsp-errors disable (Optional) Sets the router to purge LSPs received with checksum errors. Example: RP/0/RP0/CPU0:router(config-isis)# ignore-lsp-errors disable Step 9 interface type instance Enters interface configuration mode.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Step 15 Command or Action Purpose end Saves configuration changes.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Configuring Nonstop Forwarding for IS-IS This task explains how to configure your router with NSF that allows the Cisco IOS XR software to resynchronize the IS-IS link-state database with its IS-IS neighbors after a process restart.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Step 4 Command or Action Purpose nsf interface-expires number Configures the number of resends of an acknowledged NSF-restart acknowledgment. Example: • RP/0/RP0/CPU0:router(config-isis)# nsf interface-expires 1 Step 5 nsf interface-timer seconds If the resend limit is reached during the NSF restart, the restart falls back to a cold restart.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Configuring Authentication for IS-IS This task explains how to configure authentication for IS-IS. This task is optional. Authentication is available to limit the establishment of adjacencies by using the hello-password configuration, and to limit the exchange of LSPs by using the LSP password. IS-IS supports plain-text authentication, which does not provide security against hackers or other unauthorized users.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Step 3 Command or Action Purpose lsp-password {hmac-md5 | text} {clear | encrypted} password [level {1 | 2}] [send-only] [snp send-only] Configures the LSP authentication password. Example: RP/0/RP0/CPU0:router(config-isis)# lsp-password hmac-md5 encrypted password1 level 1 Step 4 interface type instance • The hmac-md5 keyword specifies that the password is used in HMAC-MD5 authentication.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Step 5 Command or Action Purpose hello-password {hmac-md5 | text} {clear | encrypted} password [level {1 | 2}] [send-only] Configures the authentication password for an IS-IS interface. Example: RP/0/RP0/CPU1:router(config-isis-if)# hello-password text clear mypassword Step 6 Saves configuration changes.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Restrictions MPLS traffic engineering currently supports only a single IS-IS level and does not support routing and signaling of LSPs over unnumbered IP links. Therefore, do not configure the feature over those links. SUMMARY STEPS 1. configure 2. router isis instance-id 3. address-family {ipv4 | ipv6} [unicast] 4. mpls traffic-eng level {1 | 2} 5.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Step 5 Command or Action Purpose mpls traffic-eng router-id {ip-address | interface-name} Specifies that the MPLS TE router identifier for the node is the IP address and or name associated with a given interface.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Tuning Adjacencies for IS-IS on Point-to-Point Interfaces This task explains how to enable logging of adjacency state changes, alter the timers for IS-IS adjacency packets, and display various aspects of adjacency state. Tuning your IS-IS adjacencies increases network stability when links are congested. This task is optional.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router isis instance-id Example: Enables IS-IS routing for the specified routing instance, and places the router in router configuration mode.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Step 8 Command or Action Purpose hello-password {hmac-md5 | text} {clear | encrypted} password [level {1 | 2}] [send-only] Specifies that this system include authentication in the hello packets and requires successful authentication of the hello packet from the neighbor to establish an adjacency.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Step 12 Command or Action Purpose show isis [instance instance-id] interface [type instance] [brief | detail] [level {1 | 2}] (Optional) Displays information about the IS-IS interface.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router isis instance-id Example: Enables IS-IS routing for the specified routing instance, and places the router in router configuration mode.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Step 7 Command or Action Purpose end Saves configuration changes.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router isis instance-id Example: Enables IS-IS routing for the specified routing process, and places the router in router configuration mode. In this example, the IS-IS instance is called isp.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software SUMMARY STEPS 1. configure 2. router isis instance-id 3. set-overload-bit [on-startup {delay | wait-for-bgp}] [level {1 | 2}] 4. address-family {ipv4 | ipv6} [unicast] 5. default-information originate [route-map map-name] 6. redistribute isis instance [level-1 | level-2 | level-1-2] [metric metric] [metric-type {internal | external}] policy policy-name] 7.
Implementing IS-IS on Cisco IOS XR Software How to Implement IS-IS on Cisco IOS XR Software Step 5 Command or Action Purpose default-information originate [route-map map-name] (Optional) Injects a default IPv4 or IPv6 route into an IS-IS routing domain. • The route-map keyword and map-name argument specify the conditions under which the IPv4 or IPv6 default route is advertised. • If the route-map keyword is omitted, then the IPv4 or IPv6 default route is unconditionally advertised at Level 2.
Implementing IS-IS on Cisco IOS XR Software Configuration Examples for Implementing IS-IS on Cisco IOS XR Software Step 10 Command or Action Purpose set-attached-bit (Optional) Configures an IS-IS instance with an attached bit in the Level 1 LSP. Example: RP/0/RP0/CPU0:router(config-isis-af)# set-attached-bit Step 11 Saves configuration changes.
Implementing IS-IS on Cisco IOS XR Software Configuration Examples for Implementing IS-IS on Cisco IOS XR Software address-family ipv4 unicast ! address-family ipv6 unicast ! exit ! interface POS0/3/0/0 ipv4 address 10.0.1.3 255.255.255.0 ipv6 address 2001::1/64 Configuring Multitopology IS-IS for IPv6: Example The following example shows multitopology IS-IS being configured in IPv6. You need not enable IS-IS for IPv6 globally on the router. router isis isp net 49.0000.0000.0001.
Implementing IS-IS on Cisco IOS XR Software Where to Go Next Where to Go Next To implement more IP routing protocols, see the following document modules: • Implementing OSPF on Cisco IOS XR Software • Implementing BGP on Cisco IOS XR Software Additional References The following sections provide references related to implementing IS-IS on Cisco IOS XR software.
Implementing IS-IS on Cisco IOS XR Software Additional References RFCs RFCs Title RFC 1142 OSI IS-IS Intra-domain Routing Protocol RFC 1195 Use of OSI IS-IS for Routing in TCP/IP and Dual Environments RFC 2763 Dynamic Hostname Exchange Mechanism for IS-IS RFC 2966 Domain-wide Prefix Distribution with Two-Level IS-IS RFC 2973 IS-IS Mesh Groups RFC 3277 IS-IS Transient Blackhole Avoidance RFC 3373 Three-Way Handshake for IS-IS Point-to-Point Adjacencies RFC 3567 IS-IS Cryptographic Authentic
Implementing IS-IS on Cisco IOS XR Software Additional References Cisco IOS XR Routing Configuration Guide RC-126
Implementing OSPF on Cisco IOS XR Software Open Shortest Path First (OSPF) is an Interior Gateway Protocol (IGP) developed by the OSPF working group of the Internet Engineering Task Force (IETF). Designed expressly for IP networks, OSPF supports IP subnetting and tagging of externally derived routing information. OSPF also allows packet authentication and uses IP multicast when sending and receiving packets.
Implementing OSPF on Cisco IOS XR Software Prerequisites for Implementing OSPF on Cisco IOS XR Software Prerequisites for Implementing OSPF on Cisco IOS XR Software The following are prerequisites for implementing OSPF on Cisco IOS XR Software: • You must be in a user group associated with a task group that includes the proper task IDs for OSPF commands. Task IDs for commands are listed in the Cisco IOS XR Task ID Reference Guide.
Implementing OSPF on Cisco IOS XR Software Information About Implementing OSPF on Cisco IOS XR Software • Nonstop Forwarding for OSPF Version 2, page RC-140 • Load Balancing in OSPF Version 2 and OSPFv3, page RC-141 OSPF Functional Overview OSPF is a routing protocol for IP. It is a link-state protocol, as opposed to a distance-vector protocol. A link-state protocol makes its routing decisions based on the states of the links that connect source and destination machines.
Implementing OSPF on Cisco IOS XR Software Information About Implementing OSPF on Cisco IOS XR Software OSPF typically requires coordination among many internal routers: Area Border Routers (ABRs), which are routers attached to multiple areas, and Autonomous System Border Routers (ASBRs) that export reroutes from other sources (for example, IS-IS, BGP, or static routes) into the OSPF topology.
Implementing OSPF on Cisco IOS XR Software Information About Implementing OSPF on Cisco IOS XR Software Comparison of Cisco IOS XR OSPFv3 and OSPFv2 Much of the OSPFv3 protocol is the same as in OSPFv2. OSPFv3 is described in RFC 2740. The key differences between the Cisco IOS XR OSPFv3 and OSPFv2 protocols are as follows: • OSPFv3 expands on OSPFv2 to provide support for IPv6 routing prefixes and the larger size of IPv6 addresses.
Implementing OSPF on Cisco IOS XR Software Information About Implementing OSPF on Cisco IOS XR Software Tip Understanding hierarchical CLI and CLI inheritance saves you considerable configuration time. See the “Configuring Authentication at Different Hierarchical Levels for OSPF Version 2” section on page RC-155 to understand how to implement these fundamentals.
Implementing OSPF on Cisco IOS XR Software Information About Implementing OSPF on Cisco IOS XR Software Areas Areas allow the subdivision of an autonomous system into smaller, more manageable networks or sets of adjacent networks. As shown in Figure 6, autonomous system A consists of three areas: Area 0, Area 1, and Area 2. OSPF hides the topology of an area from the rest of the autonomous system. The network topology for an area is visible only to routers inside that area.
Implementing OSPF on Cisco IOS XR Software Information About Implementing OSPF on Cisco IOS XR Software Routers The OSPF network is composed of ABRs, ASBRs, and interior routers. Area Border Routers (ABR) ABRs are routers with multiple interfaces that connect directly to networks in two or more areas. An ABR runs a separate copy of the OSPF algorithm and maintains separate routing data for each area that is attached to, including the backbone area.
Implementing OSPF on Cisco IOS XR Software Information About Implementing OSPF on Cisco IOS XR Software • The primary IPv4 address of the interface specified by the OSPF router-id command. • The 32-bit numeric value specified by the router-id command in global configuration mode. (This value must be an IPv4 address assigned to an interface on this router.) • By using the highest IPv4 address on a loopback interface in the system if the router is booted with saved loopback address configuration.
Implementing OSPF on Cisco IOS XR Software Information About Implementing OSPF on Cisco IOS XR Software Note MD5 authentication supports multiple keys, requiring that a key number be associated with a key. Authentication Strategies Authentication can be specified for an entire process or area, or on an interface or a virtual link. An interface or virtual link can be configured for only one type of authentication, not both.
Implementing OSPF on Cisco IOS XR Software Information About Implementing OSPF on Cisco IOS XR Software The software looks at the priority of the routers on the segment to determine which routers are the DR and BDR. The router with the highest priority is elected the DR. If there is a tie, then the router with the higher router ID takes precedence. After the DR is elected, the BDR is elected the same way. A router with a router priority set to zero is ineligible to become the DR or BDR.
Implementing OSPF on Cisco IOS XR Software Information About Implementing OSPF on Cisco IOS XR Software • Network LSA (Type 2)—Describes the link state and cost information for all routers attached to a multiaccess network segment. This LSA lists all OSPF routers that have interfaces attached to the network segment. Only the elected designated router for the network segment can generate and track the network LSA for the segment.
Implementing OSPF on Cisco IOS XR Software Information About Implementing OSPF on Cisco IOS XR Software In the case in which an area cannot be connected to Area 0, you must configure a virtual link between that area and Area 0. The two endpoints of a virtual link are ABRs, and the virtual link must be configured in both routers. The common nonbackbone area to which the two routers belong is called a transit area.
Implementing OSPF on Cisco IOS XR Software Information About Implementing OSPF on Cisco IOS XR Software The interval at which the SPF calculations occur is chosen dynamically and based on the frequency of topology changes in the network. The chosen interval is within the boundary of the user-specified value ranges. If network topology is unstable, SPF throttling calculates SPF scheduling intervals to be longer until topology becomes stable.
Implementing OSPF on Cisco IOS XR Software Information About Implementing OSPF on Cisco IOS XR Software through intelligent line cards while the standby Route Processor (RP) assumes control from the failed RP. The ability of line cards to remain up through a failover and to be kept current with the Forwarding Information Base (FIB) on the active RP is key to Cisco IOS XR NSF operation. Routing protocols, such as OSPF, run only on the active RP or DRP and receive routing updates from their neighbor routers.
Implementing OSPF on Cisco IOS XR Software Information About Implementing OSPF on Cisco IOS XR Software Modes of Graceful Restart Operation The two operational modes that a router can be in for this feature are restart mode and helper mode. Restart mode occurs when the OSPFv3 process is doing a graceful restart. Helper mode refers to the neighbor routers that continue to forward traffic on established OSPFv3 routes while OSPFv3 is restarting on a neighboring router.
Implementing OSPF on Cisco IOS XR Software Information About Implementing OSPF on Cisco IOS XR Software • Upon entering helper mode, a router performs its helper function for a specific period of time. This time period is the lifetime value from the router that is in restart mode—minus the value of lsage in the received grace LSA. If the graceful restart succeeds in time, the helper’s timer is stopped before it expires.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software • If graceful restart is enabled, the adjacency creation time of all the neighbors is saved in the system database (SysDB). The purpose for saving the creation time is so that OSPFv3 can use the original adjacency creation time to display the uptime for that neighbor after the restart.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software • Verifying OSPF Configuration and Operation, page RC-180 (optional) • Configuring OSPFv3 Graceful Restart, page RC-181 (optional) • Enabling Multicast-Intact for OSPFv2, page RC-186 (optional) Enabling OSPF This task explains how to perform the minimum OSPF configuration on your router that is to enable an OSPF process with a router ID, configure a backbone or nonbackbone area, and then assign one or more inter
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router ospf process-name or router ospfv3 process-name Example: Enables OSPF routing for the specified routing process, and places the router in router configuration mode.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 7 Command or Action Purpose log adjacency changes [detail] [enable | disable] (Optional) Requests notification of neighbor changes. Example: • By default, this feature is enabled. • The messages generated by neighbor changes are considered notifications, which are categorized as severity Level 5 in the logging console command.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software 6. stub or nssa 7. default-cost cost 8. end or commit 9. Repeat this task on all other routers in the stub area or NSSA. DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 5 Command or Action Purpose stub [no-summary] Defines the nonbackbone area as a stub area. or • See the “Configuring Stub and Not-so-Stubby Area Types” section on page RC-147. • Specify the no-summary keyword to further reduce the number of LSAs sent into a stub area. This keyword prevents the ABR from sending summary link-state advertisements (Type 3) in the stub area.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 8 Command or Action Purpose end Saves configuration changes.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software 9. neighbor ip-address [priority number] [poll-interval seconds] [cost number] or neighbor ipv6-link-local-address [priority number] [poll-interval seconds] [cost number] [database-filter [all]] 10. Repeat Step 9 for all neighbors on the interface. 11. exit 12. interface type instance 13.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 5 Command or Action Purpose network {broadcast | non-broadcast | {point-to-multipoint [non-broadcast] | point-to-point}} Configures the OSPF network type to a type other than the default for a given medium. • The example sets the network type to NBMA.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 9 Command or Action Purpose neighbor ip-address [priority number] [poll-interval seconds][cost number] Configures the IPv4 address of OSPF neighbors interconnecting to nonbroadcast networks. or neighbor ipv6-link-local-address [priority number] [poll-interval seconds][cost number] [database-filter [all]] or Configures the link-local IPv6 address of OSPFv3 neighbors.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 13 Command or Action Purpose neighbor ip-address [priority number] [poll-interval seconds][cost number] [database-filter [all]] Configures the IPv4 address of OSPF neighbors interconnecting to nonbroadcast networks. or or neighbor ipv6-link-local-address [priority number] [poll-interval seconds][cost number] [database-filter [all]] Configures the link-local IPv6 address of OSPFv3 neighbors.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Command or Action Purpose Step 14 Repeat Step 13 for all neighbors on the interface. — Step 15 end Saves configuration changes.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software 5. message-digest-key key-id md5 {key | clear key | encrypted key} 6. area area-id 7. interface type instance 8. Repeat Step 7 for each interface that must communicate, using the same authentication. 9. exit 10. area area-id 11. authentication [message-digest | null] 12. interface type instance 13. Repeat Step 7 for each interface that must communicate, using the same authentication. 14.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 6 Command or Action Purpose area area-id Enters area configuration mode and configures a backbone area for the OSPF process. Example: RP/0/RP0/CPU0:router(config-ospf)# area 0 Step 7 interface type instance Example: Enters interface configuration mode and associates one or more interfaces to the backbone area.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 15 Command or Action Purpose authentication [message-digest | null] Specifies no authentication on POS interface 0/3/0/0, overriding the plain text authentication specified for area 1. • Example: RP/0/RP0/CPU0:router(config-ospf-ar-if)# authentication null Step 16 By default, all of the interfaces configured in the same area inherit the same authentication values of the area. Saves configuration changes.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router ospf process-name or router ospfv3 process-name Example: Enables OSPF routing for the specified routing process, and places the router in router configuration mode.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 7 Command or Action Purpose timers lsa group-pacing seconds Changes the interval at which OSPF link-state LSAs are collected into a group for flooding. The default is 240 seconds. Example: RP/0/RP0/CPU0:router(config-ospf)# timers lsa group-pacing 1000 Step 8 Saves configuration changes.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software • For a virtual link to be successful, you need a stable router ID at each end of the virtual link. You do not want them to be subject to change, which could happen if they are assigned by default (See the “OSPF Process and Router ID” section on page RC-134 for an explanation of how the router ID is determined.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose show ospf [process-name] (Optional) Displays general information about OSPF routing processes. or show ospfv3 [process-name] • Example: The output displays the router ID of the local router. You need this router ID to configure the other end of the link.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 8 Command or Action Purpose message-digest-key key-id md5 {key | clear key | encrypted key} Defines an OSPF virtual link. Example: RP/0/RP0/CPU0:router(config-ospf-ar-vl)# message-digest-key 4 md5 yourkey • See the “Virtual Link and Transit Area for OSPF” section on page RC-138 to understand a virtual link. • The key-id argument is a number in the range from 1 to 255.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Examples In the following example, the show ospfv3 virtual links EXEC command verifies that the OSPF_VL0 virtual link to the OSPFv3 neighbor is up, the ID of the virtual link interface is 2, and the IPv6 address of the virtual link endpoint is 2003:3000::1. RP/0/RP0/CPU0:router# show ospfv3 virtual-links Virtual Links for OSPFv3 1 Virtual Link OSPF_VL0 to router 10.0.0.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software 7. end or commit DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router ospf process-name or router ospfv3 process-name Example: Enables OSPF routing for the specified routing process, and places the router in router configuration mode.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 6 Command or Action Purpose interface type instance Enters interface configuration mode and associates one or more interfaces to the area. Example: RP/0/RP0/CPU0:router(config-ospf-ar)# interface POS 0/2/0/3 Step 7 Saves configuration changes.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software 5. summary-prefix address mask [not-advertise] [tag tag] or summary-prefix ipv6-prefix/prefix-length [not-advertise] [tag tag] 6. end or commit DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 4 Command or Action Purpose redistribute protocol [process-id] {level-1 | level-1-2 | level-2} [metric metric-value] [metric-type type-value] [match {internal | external [1 | 2} | nssa-external [1 | 2}] [tag tag-value] [route-map map-tag | policy policy-tag] Redistributes OSPF routes from one routing domain to another routing domain.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 5 Command or Action Purpose summary-prefix address mask [not-advertise] [tag tag] (Optional) Creates aggregate addresses for OSPF. or or summary-prefix ipv6-prefix/prefix-length [not-advertise] [tag tag] (Optional) Creates aggregate addresses for OSPFv3. Example: • This command provides external route summarization of the non-OSPF routes.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Configuring OSPF Shortest Path First Throttling This task explains how to configure SPF scheduling in millisecond intervals and potentially delay SPF calculations during times of network instability. This task is optional. Prerequisites See the “OSPF Shortest Path First Throttling” section on page RC-139 for information about OSPF SPF throttling. SUMMARY STEPS 1. configure 2.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 3 Command or Action Purpose router-id {ipv4-address | interface-type interface-instance} Configures a router ID for the OSPF process. Note We recommend using a stable IPv4 address as the router ID. Example: RP/0/RP0/CPU0:router(config-ospf)# router-id 192.168.4.3 Step 4 timers throttle spf spf-start spf-hold spf-max-wait Sets SPF throttling timers.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 7 Command or Action Purpose end Saves configuration changes.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Non-Stop Forwarding enabled Note For a description of each output display field, see the show ospf command in the OSPF Commands on Cisco IOS XR Software module in the Cisco IOS XR Routing Command Reference document. Configuring Nonstop Forwarding for OSPF Version 2 This task explains how to configure OSPF NSF on your NSF-capable router. This task is optional.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router ospf process-name Enables OSPF routing for the specified routing process, and places the router in router configuration mode.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 5 Command or Action Purpose nsf interval seconds Sets the minimum time between NSF restart attempts. Note Example: RP/0/RP0/CPU0:router(config-ospf)# nsf interval 120 Step 6 When you use this command, the OSPF process must be up for at least 90 seconds before OSPF attempts to perform an NSF restart. Saves configuration changes.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Restrictions MPLS traffic engineering currently supports only a single OSPF area. SUMMARY STEPS 1. configure 2. router ospf process-name 3. router-id {ipv4-address | interface-type interface-instance} 4. mpls traffic-eng area area-id 5. mpls traffic-eng router-id {ip-address | interface-type interface-instance} 6. area area-id 7. interface type instance 8. end or commit 9.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 5 Step 6 Command or Action Purpose mpls traffic-eng router-id {ip-address | interface-type interface-instance} (Optional) Specifies that the traffic engineering router identifier for the node is the IP address associated with a given interface. Example: • This IP address is flooded to all nodes in TE LSAs.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 8 Command or Action Purpose end Saves configuration changes.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Sample Output for the show ospf mpls traffic-eng Command In the following example, the show ospf mpls traffic-eng EXEC command verifies that the MPLS TE fragments are configured correctly: RP/0/RP0/CPU0:router# show ospf 1 mpls traffic-eng fragment OSPF Router with ID (192.168.4.3) (Process ID 1) Area 0 has 1 MPLS TE fragment. Area instance is 3. MPLS router address is 192.168.4.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Priority Priority Priority Priority Affinity 0 : 3125000 2 : 3125000 4 : 3125000 6 : 3125000 Bit :0 Priority Priority Priority Priority 1 3 5 7 : : : : 3125000 3125000 3125000 3125000 Sample Output for the show ospf Command After Configuring MPLS TE In the following example, the show route ospf EXEC command verifies that the MPLS TE tunnels replaced POS interface 0/3/0/0 and that configuration was performed cor
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Step 3 Command or Action Purpose show ospf [process-name] database (Optional) Displays the lists of information related to the OSPF database for a specific router. • Example: RP/0/RP0/CPU0:router# show ospf group2 database Step 4 show ospf [process-name] [area-id] flood-list interface type instance The various forms of this command deliver information about different OSPF LSAs.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Enabling Graceful Restart This section describes how to enable an OSPFv3 graceful restart on the current router. By default, this feature is disabled. SUMMARY STEPS 1. configuration 2. router ospfv3 3. graceful-restart DETAILED STEPS Step 1 Command or Action Purpose config Enters global configuration mode.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose config Enters global configuration mode. Example: RP/0/RP0/CPU0:single10-hfr#config RP/0/RP0/CPU0:single10-hfr(config) Step 2 router ospfv3 Example: RP/0/RP0/CPU0:single10-hfr(config)# router ospfv3 test Step 3 graceful-restart lifetime Enters router configuration mode for OSPFv3.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose config Enters global configuration mode. Example: RP/0/RP0/CPU0:single10-hfr#config RP/0/RP0/CPU0:single10-hfr(config) Step 2 router ospfv3 Example: RP/0/RP0/CPU0:single10-hfr(config)# router ospfv3 test Step 3 graceful-restart interval Enters router configuration mode for OSPFv3.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose config Enters global configuration mode. Example: RP/0/RP0/CPU0:single10-hfr#config RP/0/RP0/CPU0:single10-hfr(config) Step 2 router ospfv3 Example: RP/0/RP0/CPU0:single10-hfr(config)# router ospfv3 test Step 3 graceful-restart helper Enters router configuration mode for OSPFv3.
Implementing OSPF on Cisco IOS XR Software How to Implement OSPF on Cisco IOS XR Software Displaying Graceful Restart Information for an OSPFv3 Instance The following screen output shows the link state for the instance of OSPFv3 called test: RP/0/0/CPU0:LA#show ospfv3 test database grace OSPFv3 Router with ID (2.2.2.2) (Process ID test) ADV Router 1.1.1.1 2.2.2.2 Router Link States (Area 0) Age Seq# Fragment ID 1949 0x8000000e 0 2007 0x80000011 0 ADV Router 1.1.1.1 s2.2.2.
Implementing OSPF on Cisco IOS XR Software Configuration Examples for Implementing OSPF on Cisco IOS XR Software Step 3 Command or Action Purpose mpls traffic-eng multicast-intact Enables multicast-intact. Example: RP/0/RP0/CPU0:router(config-isis)# mpls traffic-eng multicast-intact Step 4 Saves configuration changes.
Implementing OSPF on Cisco IOS XR Software Configuration Examples for Implementing OSPF on Cisco IOS XR Software Cisco IOS XR for OSPF Version 2 Configuration: Example The following example shows how an OSPF interface is configured for an area in Cisco IOS XR software. In Cisco IOS XR software, area 0 must be explicitly configured with the area command and all interfaces that are in the range from 10.1.2.0 to 10.1.2.255 are bound to area 0.
Implementing OSPF on Cisco IOS XR Software Configuration Examples for Implementing OSPF on Cisco IOS XR Software router ospf 1 router-id 10.2.3.4 area 0 interface POS 0/3/0/0 ! area 1 interface POS 0/3/0/1 ! ! CLI Inheritance and Precedence for OSPF Version 2: Example The following example configures the cost parameter at different hierarchical levels of the OSPF topology, and illustrates how the parameter is inherited and how only one setting takes precedence.
Implementing OSPF on Cisco IOS XR Software Configuration Examples for Implementing OSPF on Cisco IOS XR Software interface POS 0/2/0/3 ! interface POS 0/3/0/3 cost 1 ! ! MPLS TE for OSPF Version 2: Example The following example shows how to configure the OSPF portion of MPLS TE. However, you still need to build an MPLS TE topology and create an MPLS TE tunnel. See the Cisco IOS XR MPLS Configuration Guide for information.
Implementing OSPF on Cisco IOS XR Software Configuration Examples for Implementing OSPF on Cisco IOS XR Software ABR Totally Stub Area for OSPFv3: Example The following example shows that area 1 is configured as a totally stub area: router ospfv3 1 router-id 10.0.0.217 area 0 interface POS 0/2/0/1 area 1 stub no-summary interface POS 0/2/0/0 Route Redistribution for OSPFv3: Example The following example uses prefix lists to limit the routes redistributed from other protocols.
Implementing OSPF on Cisco IOS XR Software Where to Go Next Virtual Link Configured with MD5 Authentication for OSPF Version 2: Example The following examples show how to configure a virtual link to your backbone and apply MD5 authentication. You must perform the steps described on both ABRs at each end of the virtual link.
Implementing OSPF on Cisco IOS XR Software Additional References Additional References The following sections provide references related to implementing OSPF on Cisco IOS XR software.
Implementing OSPF on Cisco IOS XR Software Additional References Technical Assistance Description Link http://www.cisco.com/techsupport The Cisco Technical Support website contains thousands of pages of searchable technical content, including links to products, technologies, solutions, technical tips, and tools. Registered Cisco.com users can log in from this page to access even more content.
Implementing and Monitoring RIB on Cisco IOS XR Software Routing Information Base (RIB) is a distributed collection of information about routing connectivity among all nodes of a network. Each router maintains a RIB containing the routing information for that router. RIB stores the best routes from all routing protocols that are running on the system. This module describes the tasks you need to perform to implement and monitor RIB on your Cisco IOS XR network.
Implementing and Monitoring RIB on Cisco IOS XR Software Prerequisites for Implementing RIB on Cisco IOS XR Software Prerequisites for Implementing RIB on Cisco IOS XR Software • To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.
Implementing and Monitoring RIB on Cisco IOS XR Software Information About RIB Configuration RIB Administrative Distance Forwarding is done based on the longest prefix match. If you are forwarding a packet destined to 10.0.2.1, you prefer 10.0.2.0/24 over 10.0.0.0/16 because the mask /24 is longer (and more specific) than a /16. Routes from different protocols that have the same prefix and length are chosen based on administrative distance.
Implementing and Monitoring RIB on Cisco IOS XR Software How to Deploy and Monitor RIB How to Deploy and Monitor RIB To deploy and monitor RIB, you must understand the following concepts: • Verifying RIB Configuration Using the Routing Table, page RC-198 (required) • Verifying Networking and Routing Problems, page RC-198 (required) Verifying RIB Configuration Using the Routing Table This task verifies the RIB configuration to ensure that RIB is running on the RP and functioning properly by checking the
Implementing and Monitoring RIB on Cisco IOS XR Software How to Deploy and Monitor RIB 5. show route [afi-all | ipv4 | ipv6] [unicast | multicast | safi-all] local [interface] 6. show route [afi-all | ipv4 | ipv6] [unicast | multicast | safi-all] ip-address mask longer-prefixes 7.
Implementing and Monitoring RIB on Cisco IOS XR Software Configuration Examples for RIB Monitoring Step 6 Command or Action Purpose show route [afi-all | ipv4 | ipv6] [unicast | multicast | safi-all] ip-address mask longer-prefixes Displays the current routes in RIB that share a given number of bits with a given network. Example: RP/0/RP0/CPU0:router# show route ipv4 unicast 192.168.
Implementing and Monitoring RIB on Cisco IOS XR Software Configuration Examples for RIB Monitoring L C L S 172.20.16.1/32 is directly connected, 1d21h, ATM4/0.1 10.6.100.0/24 is directly connected, 1d21h, Loopback1 10.6.200.21/32 is directly connected, 1d21h, Loopback0 192.168.40.0/24 [1/0] via 172.20.16.
Implementing and Monitoring RIB on Cisco IOS XR Software Where to Go Next L L 192.168.20.2/32 is directly connected, 00:13:27, GigabitEthernet2/0 10.254.254.1/32 is directly connected, 00:13:26, GigabitEthernet2/2 Output of show route longer-prefixes Command: Example The following is sample output from the show route longer-prefixes command: RP/0/RP0/CPU0:router# show route ipv4 172.16.0.
Implementing and Monitoring RIB on Cisco IOS XR Software Additional References Additional References The following sections provide references related to implementing RIB on Cisco IOS XR software: Related Documents Related Topic Document Title Routing Information Base commands: complete RIB Commands on Cisco IOS XR Software in the Cisco IOS XR command syntax, command modes, command history, Routing Command Reference, Release 3.
Implementing and Monitoring RIB on Cisco IOS XR Software Additional References RFCs RFCs Title No new or modified RFCs are supported by this feature, and support for existing RFCs has not been modified by this feature. — Technical Assistance Description Link http://www.cisco.com/techsupport The Cisco Technical Support website contains thousands of pages of searchable technical content, including links to products, technologies, solutions, technical tips, and tools. Registered Cisco.
Implementing Routing Policy on Cisco IOS XR Software A routing policy instructs the router to inspect routes, filter them, and potentially modify their attributes as they are accepted from a peer, advertised to a peer, or redistributed from one routing protocol to another. Routing protocols make decisions to advertise, aggregate, discard, distribute, export, hold, import, redistribute and otherwise modify routes based on configured routing policy.
Implementing Routing Policy on Cisco IOS XR Software Prerequisites for Implementing Routing Policy Prerequisites for Implementing Routing Policy The following are prerequisites for implementing Routing Policy on Cisco IOS XR Software: • To use this command, you must be in a user group associated with a task group that includes the proper task IDs.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy policy. For example, three policies that are identical in every way except for the local preference value they set can be represented as one common parameterized policy that takes the varying local preference value as a parameter to the policy. The policy language introduces the notion of sets. Sets are containers of similar data that can be used in route attribute matching and setting operations.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy surrounded by parentheses as follows: (,,, ...), where is an entry of an item appropriate to the type of usage such as a prefix or a community value. The following is an example using an inline community set: route-policy sample-inline if community matches-any ([10..
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy This set matches the same AS paths as the previously named set, but does not require the extra effort of creating a named set separate from the policy that uses it. community-set A community-set holds community values for matching against the BGP community attribute. A community is a 32-bit quantity.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy Inline Form (RT:1.2.3.4:666, RT:1234:6667, SoO:1.2.3.4:777, SoO:45678:777) (RT:$ipaddr:666, RT:1234:$tag, SoO:1.2.3.4:777, SoO:$tag2:777) As with community sets, the inline form supports parameterization within parameterized policies. Either portion of the extended community value can be parameterized. Every extended community-set must contain at least one extended community value.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy The following prefix-set consists entirely of invalid prefix match specifications: prefix-set ILLEGAL-PREFIX-EXAMPLES 10.1.1.1 ge 16, 10.1.2.1 le 16, 10.1.3.0/24 le 23, 10.1.4.0/24 ge 33, 10.1.5.0/25 ge 29 le 28 end-set Neither the minimum length nor maximum length is valid without a mask length. The maximum length must be at least the mask length.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy route-policy quickstart-drop drop end-policy Ignore routes with specific AS numbers in the path The following example shows the policy definition in three parts. First, the as-path-set command defines three regular expressions to match against an AS path. Second, the route-policy command applies the AS path set to a route.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy route-policy quickstart-localpref if community matches-any quickstart-communities then set local-preference 31 endif pass end-policy Persistent Remarks The following example shows how comments are placed in the policy to clarify the meaning of the entries in the set and the statements in the policy. The remarks are persistent, meaning they remain attached to the policy.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy route-policy drop-everything drop end-policy The name serves as a handle for binding the policy to protocols. To remove a policy definition, issue the no route-policy name command. Policies may also refer to other policies such that common blocks of policy can be reused.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy route-policy origin-10 if as-path originates-from ‘10’ then apply param-example(10) else pass endif end-policy route-policy origin-20 if as-path originates-from ‘20’ then apply param-example(20) else pass endif end-policy The parameterized policy param-example provides a policy definition that is expanded with the values provided as the parameters in the apply statement.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy then the expression, fully parenthesized, would look like the following: ((not med eq 10) and destination in (10.1.3.0/24)) or community matches-any ([10..25]:35) Multiple Modifications of the Same Attribute When a policy replaces the value of an attribute multiple times, the last assignment wins because all actions are executed.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy if med eq 12 then set med 42 if med eq 42 then drop endif endif This policy never executes the drop statement because the second test (med eq 42) sees the original, unmodified value of the MED in the route. Because the MED has to be 12 to get to the second test, the second test always returns false.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy Policy four could be rewritten in an equivalent way as follows: route-policy four-equivalent set weight 100 set med 200 set community (2:666) additive pass end-policy Note The pass statement is not required and can be removed to represent the equivalent policy in another way. Policy Verification Several different types of verification occur when policies are being defined and used.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy Attached Policy Modification Policies that are in use do, on occasion, need to be modified. Traditionally, configuration changes are done by completely removing the relevant configuration and then re-entering it. However, this allows for a window of time in which no policy is attached and the default action takes place.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy Unlike traditional !-comments in the CLI, RPL remarks persist through reboots and when configurations are saved to disk or a TFTP server and then loaded back onto the router. Disposition By default, a route is dropped at the end of policy processing unless either the policy modifies a route attribute or it passes the route by means of an explicit pass statement.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy Because the effect of an explicit drop statement is immediate, routes in 10.0.0.0/16 le 32 are dropped without any further policy processing. Other routes are then considered to see if they were advertised by autonomous system 123. If they were advertised, they are passed; otherwise, they are implicitly dropped at the end of all policy processing.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy The statements within an if statement may themselves be if statements, as shown in the following example: if community matches-any (12:34,56:78) then if med eq 150 then drop endif set local-preference 100 endif This policy example sets the value of the local preference attribute to 100 on any route that has a community value of 12:34 or 56:78 associated with it.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy With a set of parentheses to express the precedence, the result is the following: med eq 10 or ((not destination in (10.1.3.0/24)) and community matches-any ([12..34]:[56..78]) The following is another example of a complex expression: (origin is igp or origin is incomplete or not med eq 42) and next-hop in (10.0.2.2) The left conjunction is a compound condition enclosed in parentheses.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy Note The protocol configuration rejects attempts to attach policies that perform unsupported operations. The following sections describe the protocol attach points, including information on the attributes (commands) and operations that are valid for each attach point.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy router bgp 2 address-family ipv4 aggregate-address 10.0.0.0/8 policy sample . . . Dampening The dampening attach point controls the default route-dampening behavior within BGP. Unless overridden by a more specific policy on the associate peer, all routes in BGP apply the associated policy to set their dampening attributes. The following policy sets dampening values for BGP IPv4 unicast routes.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy Neighbor Export The neighbor export attach point selects the BGP routes to send to a given peer or group of peers. The routes are selected by running the set of possible BGP routes through the associated policy. Any routes that pass the policy are then sent as updates to the peer or group of peers. The routes that are sent may have had their BGP attributes altered by the policy that has been applied.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy router bgp 2 neighbor 10.0.0.1 remote-as 3 address-family ipv4 unicast route-policy sample_import in . . . Network The network attach point controls the injection of routes from the RIB into BGP. A route policy attached at this point is able to set any of the valid BGP attributes on the routes that are being injected.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy Show bgp The show bgp attach point allows the user to display selected BGP routes that pass the given policy. Any routes that are not dropped by the attached policy are displayed in a manner similar to the output of the show ip bgp command.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy RP/0/RP0/CPU0:router# show bgp policy route-policy test2 10.0.0.0/8 is advertised to 10.0.101.2 Path info: neighbor:10.0.1.2 neighbor router id:10.0.1.2 valid external best Attributes after inbound policy was applied: next hop:10.0.1.2 MET ORG AS origin:incomplete neighbor as:3 metric:10 aspath:3 Attributes after outbound policy was applied: next hop:10.0.1.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy Table 3 BGP Attributes and Operators Attribute Match Set as-path in prepend is-local length neighbor-is originates-from passes-though unique-length community is-empty delete matches-any set matches-every dampening n/a set dampening...
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy Table 4 Restricted BGP Operations by Attach Point import export aggregation redistribution prepend as-path eBGP only eBGP only n/a n/a set med igp-cost forbidden eBGP only forbidden forbidden set weight n/a forbidden n/a n/a suppress forbidden forbidden n/a forbidden OSPF Policy Attach Points This section describes each of the OSPF policy attach points and provides a summary of the O
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy route-policy OSPF-redist set metric-type type-2 if tag eq 10 then set cost 100 elseif tag eq 20 then set cost 200 else drop endif end-policy router ospf 1 redistribute isis instance_10 policy OSPF-redist . . . OSPF Attributes and Operators Table 5 summarizes the OSPF attributes and operators.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy router ospfv3 1 default-information originate policy ospfv3-originate . . . Redistribute The redistribute attach point within OSPFv3 injects routes from other routing protocol sources into the OSPFv3 link-state database, which is done by selecting the route types it wants to import from each protocol. It then sets the OSPFv3 parameters of cost and metric type.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy IS-IS Policy Attach Points This section describes each of the IS-IS policy attach points and provides a summary of the BGP attributes and operators. Redistribute The redistribute attach point within IS-IS allows routes from other protocols to be readvertised by IS-IS. The policy is a set of control structures for selecting the types of routes that a user wants to redistribute into IS-IS.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy Attached Policy Modification Policies that are in use do, on occasion, need to be modified. In the traditional configuration model, a policy modification would be done by completely removing the policy and re-entering it. However, this model allows for a window of time in which no policy is attached and default actions to be used, which is an opportunity for inconsistencies to exist.
Implementing Routing Policy on Cisco IOS XR Software Information About Implementing Routing Policy RP/0/RP0/CPU0:router# edit route-policy policy_A ---------------------------------------== MicroEMACS 3.8b () == rpl_edit.139281 == if destination in (2001::/8) then drop endif end-policy ! == MicroEMACS 3.8b () == rpl_edit.139281 == Parsing. 83 bytes parsed in 1 sec (82)bytes/sec Committing. 1 items committed in 1 sec (0)items/sec Updating.
Implementing Routing Policy on Cisco IOS XR Software How to Implement Routing Policy How to Implement Routing Policy This section contains the following procedures: • Defining a Route Policy, page RC-237 (required) • Attaching a Routing Policy to a BGP Neighbor, page RC-238 (required) • Modifying a Routing Policy Using the Microemacs Editor, page RC-240 (optional) Defining a Route Policy This task explains how to define a route policy.
Implementing Routing Policy on Cisco IOS XR Software How to Implement Routing Policy Step 3 Command or Action Purpose end-policy Ends the definition of a route policy and exits route-policy configuration mode. Example: RP/0/RP0/CPU0:router(config-rpl)# end-policy Step 4 Saves configuration changes.
Implementing Routing Policy on Cisco IOS XR Software How to Implement Routing Policy DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 router bgp as-number Example: Configures a BGP routing process and enters router configuration mode. • RP/0/RP0/CPU0:router(config)# router bgp 125 Step 3 neighbor ip-address The as-number argument identifies the autonomous system in which the router resides.
Implementing Routing Policy on Cisco IOS XR Software How to Implement Routing Policy Step 5 Command or Action Purpose route-policy policy-name {in | out} Attaches the route-policy, which must be well formed and predefined. Example: RP/0/RP0/CPU0:router(config-bgp-nbr-af)# route-policy example1 in Step 6 Saves configuration changes.
Implementing Routing Policy on Cisco IOS XR Software Configuration Examples for Implementing Routing Policy DETAILED STEPS Step 1 Command or Action Purpose edit {route-policy | prefix-set | as-path-set | community-set | extended-community-set} name Identifies the route policy, prefix set, AS path set, community set, or extended community set name to be modified.
Implementing Routing Policy on Cisco IOS XR Software Configuration Examples for Implementing Routing Policy configure route-policy sample1 if destination in test then drop else set med 200 set community (2:100) additive endif end-policy end show config running route-policy sample1 Building configuration...
Implementing Routing Policy on Cisco IOS XR Software Configuration Examples for Implementing Routing Policy endif else set community (2:999) additive endif end-policy router bgp 2 neighbor 10.0.1.2 address-family ipv4 unicast route-policy inbound-tx in Modular Inbound Policy: Example The following policy example shows how to build two inbound policies, in-100 and in-101, for two different peers.
Implementing Routing Policy on Cisco IOS XR Software Additional References pass endif end-policy ! route-policy common-inbound apply filter-bogons set origin igp set community (2:333) end-policy ! route-policy set-lpref-prepend($lpref,$as,$prependcnt) set local-preference $lpref prepend as-path $as $prependcnt end-policy Translating Cisco IOS Route Maps to Cisco IOS XR Routing Policy Language: Example RPL performs the same functions as route-maps.
Implementing Routing Policy on Cisco IOS XR Software Additional References MIBs MIBs MIBs Link There are no applicable MIBs for this module. To locate and download MIBs for selected platforms using Cisco IOS XR software, use the Cisco MIB Locator found at the following URL: http://cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml RFCs RFCs Title No new or modified RFCs are supported by this feature, and support for existing RFCs has not been modified by this feature.
Implementing Routing Policy on Cisco IOS XR Software Additional References Cisco IOS XR Routing Configuration Guide RC-246
Implementing Static Routes on Cisco IOS XR Software Static routes are user-defined routes that cause packets moving between a source and a destination to take a specified path. Static routes can be important if the Cisco IOS XR software cannot build a route to a particular destination. They are useful for specifying a gateway of last resort to which all unroutable packets are sent. This module describes the tasks you need to implement static routes on your Cisco IOS XR network.
Implementing Static Routes on Cisco IOS XR Software Prerequisites for Implementing Static Routes on Cisco IOS XR Software Prerequisites for Implementing Static Routes on Cisco IOS XR Software To use this command, you must be in a user group associated with a task group that includes the proper task IDs. For detailed information about user groups and task IDs, see the Configuring AAA Services on Cisco IOS XR Software module of the Cisco IOS XR System Security Configuration Guide.
Implementing Static Routes on Cisco IOS XR Software Information About Implementing Static Routes on Cisco IOS XR Software routes. For example, you could have routes installed by the Open Shortest Path First (OSPF) protocol with an administrative distance of 120. To have a static route that would be overridden by an OSPF dynamic route, specify an administrative distance greater than 120.
Implementing Static Routes on Cisco IOS XR Software How to Implement Static Routes on Cisco IOS XR Software Fully Specified Static Routes In a fully specified static route, both the output interface and next hop are specified. This form of static route is used when the output interface is a multiaccess one and it is necessary to explicitly identify the next hop. The next hop must be directly attached to the specified output interface.
Implementing Static Routes on Cisco IOS XR Software How to Implement Static Routes on Cisco IOS XR Software 3. end or commit DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 route {ipv4 | ipv6} {unicast | multicast} prefix mask {ip-address | interface-type interface-instance} [distance] [tag tag] [permanent] Configures an administrative distance of 110.
Implementing Static Routes on Cisco IOS XR Software How to Implement Static Routes on Cisco IOS XR Software 3. end or commit DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 route {ipv4 | ipv6} {unicast | multicast} prefix mask {ip-address | interface-type interface-instance} [distance] [tag tag] [permanent] Example: In this example, a floating static IPv6 route is being configured.
Implementing Static Routes on Cisco IOS XR Software How to Implement Static Routes on Cisco IOS XR Software Changing the Maximum Number of Allowable Static Routes This task explains how to change the maximum number of allowable static routes. Restrictions The number of static routes that can be configured on a router for a given address family is limited by default to 4000. The limit can be raised or lowered using the route maximum command.
Implementing Static Routes on Cisco IOS XR Software How to Implement Static Routes on Cisco IOS XR Software DETAILED STEPS Step 1 Command or Action Purpose configure Enters global configuration mode. Example: RP/0/RP0/CPU0:router# configure Step 2 route maximum {ipv4 | ipv6} value Example: RP/0/RP0/CPU0:router(config)# route maximum ipv4 10000 Step 3 Changes the maximum number of allowable static routes. • Specify IPv4 or IPv6 address prefixes.
Implementing Static Routes on Cisco IOS XR Software Configuration Examples Configuration Examples This section provides the following configuration examples: • Configuring Traffic Discard: Example • Configuring a Fixed Default Route: Example • Configuring a Floating Static Route: Example Configuring Traffic Discard: Example Configuring a static route to point at interface null 0 may be used for discarding traffic to a particular prefix.
Implementing Static Routes on Cisco IOS XR Software Additional References Additional References The following sections provide references related to implementing static routes on Cisco IOS XR software. Related Documents Related Topic Document Title Static routes commands: complete command syntax, command modes, command history, defaults, usage guidelines, and examples Static and Utility Routing Commands on Cisco IOS XR Software, Release 3.
I N D EX BGP (Border Gateway Protocol) HC Cisco IOS XR Interface and Hardware Component Configuration Guide IC Cisco IOS XR IP Addresses and Services Configuration Guide MCC Cisco IOS XR Multicast Configuration Guide MPC Cisco IOS XR MPLS Configuration Guide QC Cisco IOS XR Modular Quality of Service Configuration Guide description RC Cisco IOS XR Routing Configuration Guide functional overview SC Cisco IOS XR System Security Configuration Guide inheritance, monitoring SMC Cisco IOS XR Sy
Index bgp dampening command bgp redistribute-internal command RC-49 bgp default local-preference command bgp global address family submode aggregate-address command bgp dampening command distance bgp command network command bgp router submode RC-36 RC-5 bgp bestpath as-path ignore command RC-5 RC-40 bgp bestpath compare-routerid command RC-44 RC-49 RC-54 bgp bestpath med always command RC-40 bgp bestpath med confed command RC-40 bgp confederation identifier command RC-47 See address fam
Index distance command show bgp reexp command RC-121 dmz-link-bandwidth command RC-56 Draft-ietf-idr-bgp4-24.txt, BGP RC-80, RC-244 Draft-ietf-idr-bgp4-mib-15.txt, BGP draft-ietf-idr-cease-subcode-05.txt RC-74 show bgp summary command RC-75 show isis adjacency command RC-101 show isis adjacency-log command RC-80 show isis command RC-80 Draft-ietf-isis-igp-p2p-over-lan-05.
Index interior routers configuring RC-134 IPv6 overload bit IS-IS support configuring multitopology RIB support on router RC-88 single-topology routing authentication, configuring RC-108 configuring RC-87 isis router submode router isis command configuration ispf command RC-85 Level 1 or Level 2 routing RC-100 RC-117 ispf startup-delay command RC-91 is-type command RC-117 RC-92 RC-98 RC-84 single topology default routes L RC-93 customizing routes RC-119 link-state advertise
Index nsf interface-expires command M nsf interface-timer command maximum-paths command RC-121 nsf interval command RC-175 max-lsp-lifetime command RC-103 nsf lifetime command RC-107 mesh-group command RC-104 message-digest-key command metric-style wide command nsg enforce global command RC-156 nssa command RC-110 OSPFv2 mpls traffic-eng command network command RC-152 RC-149 stub command RC-21 RC-165 RC-149 ospf area submode multitopology authentication message-digest command RC-9
Index on an OSPF ABR types configuration and operation, verifying RC-164 description RC-137 MD5 authentication enabling RC-135 MPLS TE, configuring neighbors, adjacency RC-127 RC-145 functional overview RC-175 RC-129 instance and router ID RC-136 neighbors, nonbroadcast networks, configuring RC-150 nonstop forwarding load balancing RC-134 RC-141 LSA configuring RC-173 controlling frequency description RC-140 on an OSPF ABR policy attach points default originate redistribute typ
Index RFC 3065, Autonomous System Confederations for BGP RC-81 P password accept command password-disable command point-to-point networks RFC 3277, IS-IS Transient Blackhole Avoidance RC-57 RFC 3373, Three-Way Handshake for IS-IS Point-to-Point Adjacencies RC-125 RC-57 RC-135 RFC 3392, Capabilities Advertisement with BGP-4 policy, modifying attached RFC 3567, IS-IS Cryptopgraphic Authentication RC-235 nonattached RC-125 RFC 3623, OSPFv3 RC-235 RC-81 RC-125 RC-193 RIB (Routing Information B
Index mpls traffic-eng command retransmit-throttle-interval command RC-111 mpls traffic-eng router-id command RC-112 router isis interface submode mesh-group command redistribute isis command RC-121 set-attached-bit command RC-122 router ospf command single-topology command RC-96 router ospf configuration submode spf-interval command summary-prefix command router isis command area command RC-117 router isis configuration submode RC-92 log adjacency changes command lsp-gen-interval comma
Index Area Border Routers (ABRs) statement processing RC-134 Autonomous System Boundary Routers (ASBRs) RC-134 autonomous systems backbone area RC-209 extended community set, inline form RC-24 RC-210 extended community set, named form RC-16 names RC-238 configuration elements, editing RC-207 prefix-set RC-235 sets RC-209 RC-210 RC-207 RC-237 defining (example) enforcing, BGP RC-241 S RC-16 implementing send-buffer-size command prerequisites RC-206 inbound (example) modifying RC-
Index show isis database command show isis database-log command show isis interface command show isis lsp-log command show isis mpls command timers lsa min-interval command RC-105 timers throttle spf command RC-105 ttl-security command RC-116 update groups show isis mpls traffic-eng advertisements command RC-112 show isis neighbors command show isis spf-log command BGP configuration monitor use command RC-70 virtual link transit area (OSPFv2) RC-96 configuring example virtual-link command