user manual
Table Of Contents
- Cisco IOS XR Routing Configuration Guide
- Contents
- Preface
- Document Revision History
- Obtaining Documentation
- Documentation Feedback
- Cisco Product Security Overview
- Obtaining Technical Assistance
- Obtaining Additional Publications and Information
- Implementing BGP on Cisco IOS XR Software
- Contents
- Prerequisites for Implementing BGP on CiscoIOSXR Software
- Information About Implementing BGP on CiscoIOSXR Software
- BGP Functional Overview
- BGP Router Identifier
- BGP Default Limits
- BGP Validation of Local Next-Hop Addresses
- BGP Configuration
- No Default Address Family
- Routing Policy Enforcement
- Table Policy
- Update Groups
- BGP Best Path Algorithm
- Multiprotocol BGP
- Route Dampening
- BGP Routing Domain Confederation
- BGP Route Reflectors
- Default Address Family for show Commands
- How to Implement BGP on CiscoIOSXR Software
- Enabling BGP Routing
- Configuring a Routing Domain Confederation for BGP
- Resetting eBGP Session Immediately Upon Link Failure
- Logging Neighbor Changes
- Adjusting BGP Timers
- Changing the BGP Default Local Preference Value
- Configuring the MED Metric for BGP
- Configuring BGP Weights
- Tuning the BGP Best Path Calculation
- Indicating BGP Backdoor Routes
- Configuring Aggregate Addresses
- Redistributing iBGP Routes into IGP
- Redistributing Prefixes into Multiprotocol BGP
- Configuring BGP Route Dampening
- Applying Policy When Updating the Routing Table
- Setting BGP Administrative Distance
- Configuring a BGP Neighbor Group
- Configuring a BGP Neighbor
- Configuring a Route Reflector for BGP
- Configuring BGP Route Filtering by Route Policy
- Disabling Next Hop Processing on BGP Updates
- Configuring BGP Community and Extended-Community Filtering
- Configuring Software to Store Updates from a Neighbor
- Disabling a BGP Neighbor
- Resetting Neighbors Using BGP Dynamic Inbound Soft Reset
- Resetting Neighbors Using BGP Outbound Soft Reset
- Resetting Neighbors Using BGP Hard Reset
- Clearing Caches, Tables and Databases
- Displaying System and Network Statistics
- Monitoring BGP Update Groups
- Configuration Examples for Implementing BGP on CiscoIOSXR Software
- Where to Go Next
- Additional References
- Implementing IS-IS on Cisco IOS XR Software
- Contents
- Prerequisites for Implementing IS-IS on CiscoIOSXR Software
- Restrictions for Implementing IS-IS on CiscoIOSXR Software
- Information About Implementing IS-IS on CiscoIOSXR Software
- IS-IS Functional Overview
- Key Features Supported in the CiscoIOSXR IS-IS Implementation
- IS-IS Configuration Grouping
- IS-IS Interfaces
- Multitopology Configuration
- IPv6 Routing and Configuring IPv6 Addressing
- Limit LSP Flooding
- Maximum LSP Lifetime and Refresh Interval
- Overload Bit Configuration During Multitopology Operation
- Single-Topology IPv6 Support
- Multitopology IPv6 Support
- Nonstop Forwarding
- Multi-Instance IS-IS
- Multiprotocol Label Switching Traffic Engineering
- Overload Bit on Router
- Default Routes
- Attached Bit on an IS-IS Instance
- Multicast-Intact Feature
- How to Implement IS-IS on CiscoIOSXR Software
- Enabling IS-IS and Configuring Level 1 or Level 2 Routing
- Configuring Single Topology for IS-IS
- Configuring Multitopology for IS-IS
- Controlling LSP Flooding for IS-IS
- Configuring Nonstop Forwarding for IS-IS
- Configuring Authentication for IS-IS
- Configuring MPLS Traffic Engineering for IS-IS
- Tuning Adjacencies for IS-IS on Point-to-Point Interfaces
- Setting SPF Interval for a Single-Topology IPv4 and IPv6 Configuration
- Enabling Multicast-Intact for IS-IS
- Customizing Routes for IS-IS
- Configuration Examples for Implementing IS-IS on CiscoIOSXR Software
- Where to Go Next
- Additional References
- Implementing OSPF on Cisco IOS XR Software
- Contents
- Prerequisites for Implementing OSPF on CiscoIOSXR Software
- Information About Implementing OSPF on CiscoIOSXR Software
- OSPF Functional Overview
- Key Features Supported in the CiscoIOSXR OSPF Implementation
- Comparison of CiscoIOSXR OSPFv3 and OSPFv2
- Importing Addresses into OSPFv3
- OSPF Hierarchical CLI and CLI Inheritance
- OSPF Routing Components
- OSPF Process and Router ID
- Supported OSPF Network Types
- Route Authentication Methods for OSPF Version 2
- Neighbors and Adjacency for OSPF
- Designated Router (DR) for OSPF
- Default Route for OSPF
- Link-State Advertisement Types for OSPF Version 2
- Link-State Advertisement Types for OSPFv3
- Virtual Link and Transit Area for OSPF
- Route Redistribution for OSPF
- OSPF Shortest Path First Throttling
- Nonstop Forwarding for OSPF Version 2
- Load Balancing in OSPF Version 2 and OSPFv3
- Graceful Restart for OSPFv3
- Multicast-Intact Feature
- How to Implement OSPF on CiscoIOSXR Software
- Enabling OSPF
- Configuring Stub and Not-so-Stubby Area Types
- Configuring Neighbors for Nonbroadcast Networks
- Configuring Authentication at Different Hierarchical Levels for OSPF Version 2
- Controlling the Frequency that the Same LSA Is Originated or Accepted for OSPF
- Creating a Virtual Link with MD5 Authentication to Area 0 for OSPF
- Summarizing Subnetwork LSAs on an OSPF ABR
- Redistributing Routes from One IGP into OSPF
- Configuring OSPF Shortest Path First Throttling
- Configuring Nonstop Forwarding for OSPF Version 2
- Configuring OSPF Version 2 for MPLS Traffic Engineering
- Verifying OSPF Configuration and Operation
- Configuring OSPFv3 Graceful Restart
- Enabling Multicast-Intact for OSPFv2
- Configuration Examples for Implementing OSPF on CiscoIOSXR Software
- CiscoIOSXR for OSPF Version 2 Configuration: Example
- CLI Inheritance and Precedence for OSPF Version 2: Example
- MPLS TE for OSPF Version 2: Example
- ABR with Summarization for OSPFv3: Example
- ABR Stub Area for OSPFv3: Example
- ABR Totally Stub Area for OSPFv3: Example
- Route Redistribution for OSPFv3: Example
- Virtual Link Configured Through Area 1 for OSPFv3: Example
- Virtual Link Configured with MD5 Authentication for OSPF Version 2: Example
- Where to Go Next
- Additional References
- Implementing and Monitoring RIB on CiscoIOSXR Software
- Contents
- Prerequisites for Implementing RIB on CiscoIOSXR Software
- Information About RIB Configuration
- How to Deploy and Monitor RIB
- Configuration Examples for RIB Monitoring
- Output of show route Command: Example
- Output of show route backup Command: Example
- Output of show route best-local Command: Example
- Output of show route connected Command: Example
- Output of show route local Command: Example
- Output of show route longer-prefixes Command: Example
- Output of show route next-hop Command: Example
- Where to Go Next
- Additional References
- Implementing Routing Policy on Cisco IOS XR Software
- Implementing Static Routes on Cisco IOS XR Software
- Index
Implementing BGP on Cisco IOS XR Software
How to Implement BGP on Cisco IOS XR Software
RC-27
Cisco IOS XR Routing Configuration Guide
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. However, if the clients are fully meshed, the route reflector need not reflect
routes to clients.
As the iBGP learned routes are reflected, routing information may loop. The route reflector model has
the following mechanisms to avoid routing loops:
• Originator ID is an optional, nontransitive BGP attribute. It is a 4-byte attributed created by a route
reflector. The attribute carries the router ID of the originator of the route in the local autonomous
system. Therefore, if a misconfiguration causes routing information to come back to the originator,
the information is ignored.
• Cluster-list is an optional, nontransitive BGP attribute. It is a sequence of cluster IDs that the route
has passed. When a route reflector reflects a route from its clients to nonclient peers, and vice versa,
it appends the local cluster ID to the cluster-list. If the cluster-list is empty, a new cluster-list is
created. Using this attribute, a route reflector can identify if routing information is looped back to
the same cluster due to misconfiguration. If the local cluster ID is found in the cluster-list, the
advertisement is ignored.
Default Address Family for show Commands
Most of the show commands require the address family (afi) and subsequent address family (safi) to be
specified as arguments. The Cisco IOS XR software parser provides the ability to set the afi and safi so
it is not necessary to specify them while executing a show command. The parser commands are:
• set default-afi {ipv4 | ipv6 | all}
• set default-safi {unicast | multicast | all}
The parser automatically sets the default afi value to ipv4 and default safi value to unicast. It is
necessary to use only the parser commands to change the default afi value from ipv4 or default safi value
from unicast. Any afi or safi keyword specified in a show command overrides the values set using the
parser commands. Use the following command to check the currently set value of the afi and safi:
• show default-afi-safi
How to Implement BGP on Cisco IOS XR Software
This section contains instructions for the following tasks:
• Enabling BGP Routing, page RC-28 (required)
• Configuring a Routing Domain Confederation for BGP, page RC-31 (optional)
• Resetting eBGP Session Immediately Upon Link Failure, page RC-33 (optional)
• Logging Neighbor Changes, page RC-34 (optional)
• Adjusting BGP Timers, page RC-34 (optional)
• Changing the BGP Default Local Preference Value, page RC-35 (optional)
• Configuring the MED Metric for BGP, page RC-36 (optional)
• Configuring BGP Weights, page RC-38 (optional)