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BGP Features Roadmap

Table Of Contents

BGP Features Roadmap


BGP Features Roadmap


First Published: May 21, 2010
Last Updated: July 22, 2011

This feature roadmap lists the Cisco IOS XE features documented in the Cisco IOS XE IP Routing: BGP Configuration Guide and maps them to the documents in which they appear. The roadmap is organized so that you can select your release train and see the features in that release. Find the feature name you are searching for and click on the URL in the "Where Documented" column to access the document containing that feature.

Feature and Release Support

Table 1 lists BGP feature support for the following Cisco IOS XE software release trains:

Cisco IOS XE Release 2

Cisco IOS XE Release 3S

Use Cisco Feature Navigator to find information about platform support and software image support. Cisco Feature Navigator enables you to determine which software images support a specific software release, feature set, or platform. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.


Note Table 1 lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.


Table 1 lists the most recent release of each software train first and the features in alphabetical order within the release.

Table 1 Supported BGP Features 

Release
Feature Name
Feature Description
Where Documented
Cisco IOS XE Release 2

Cisco IOS XE Release 2.6

BGP Event-Based VPN Import

BGP Event-Based VPN Import introduces a modification to the existing Border Gateway Protocol (BGP) path import process. The enhanced BGP path import is driven by events; when a BGP path changes, all of its imported copies are updated as soon as processing is available. Convergence times are significantly reduced because there is no longer any delay in the propagation of routes due to the software waiting for a periodic scanner time interval before processing the updates.

BGP Event-Based VPN Import

Cisco IOS XE Release 2.6

BGP Support for the L2VPN Address Family

BGP support for the L2VPN address family introduces a BGP-based autodiscovery mechanism to distribute L2VPN endpoint provisioning information. BGP uses a separate L2VPN Routing Information Base (RIB) to store endpoint provisioning information, which is updated each time any Layer 2 VFI is configured. When BGP distributes the endpoint provisioning information in an update message to all its BGP neighbors, the endpoint information is used to set up a pseudowire mesh to support L2VPN-based services.

BGP Support for the L2VPN Address Family

Cisco BGP Overview

Cisco IOS XE Release 2.6

Multiprotocol BGP Support for CLNS

The Multiprotocol BGP (MP-BGP) Support for CLNS feature provides the ability to scale Connectionless Network Service (CLNS) networks. The multiprotocol extensions of Border Gateway Protocol (BGP) add the ability to interconnect separate Open System Interconnection (OSI) routing domains without merging the routing domains, thus providing the capability to build very large OSI networks.

Cisco BGP Overview

Configuring Multiprotocol BGP Support for CLNS

Cisco IOS XE Release 2.5

BGP Best External

The BGP Best External feature creates and stores a backup path in the routing information base and in Cisco Express Forwarding, so that in case of a failure, the backup path can immediately take over, thus enabling subsecond failover.

BGP Best External

Cisco IOS XE Release 2.5

BGP PIC Edge for IP and MPLS-VPN

The BGP PIC Edge feature creates and stores a backup/alternate path in the routing information base (RIB) and in Cisco Express Forwarding, so that in case of a failure, the backup/alternate path can immediately take over, thus enabling subsecond failover.

BGP PIC Edge for IP and MPLS-VPN

Cisco IOS XE Release 2.5

BGP VPLS Autodiscovery Support on Route Reflector

The BGP VPLS Autodiscovery Support on Route Reflector feature enhances the BGP Route Reflector to be able to reflect BGP VPLS prefixes without having VPLS explicitly configured on the route reflector. The route reflector reflects the VPLS prefixes to other provider edge (PE) routers so that the PEs do not need to have a full mesh of BGP sessions. The network administrator configures only the BGP VPLS address family on the route reflector.

Configuring Internal BGP Features

Cisco IOS XE
Release 2.3

BGP Support for 4-Byte ASN

The BGP Support for 4-Byte ASN feature introduced support for 4-byte autonomous system numbers. Because of increased demand for autonomous system numbers, in January 2009 the IANA will start to allocate 4-byte autonomous system numbers in the range from 65536 to 4294967295.

Cisco BGP Overview

Configuring a Basic BGP Network

Connecting to a Service Provider Using External BGP

Cisco IOS XE
Release 2.1

BGP 4 MIB Support for per-Peer Received Routes

BGP 4 MIB Support for per-Peer Received Routes introduces a new table in the CISCO-BGP4-MIB that provides the capability to query (by using Simple Network Management Protocol [SNMP] commands) for routes that are learned from individual Border Gateway Protocol (BGP) peers.

BGP 4 MIB Support for Per-Peer Received Routes

Cisco IOS XE
Release 2.1

BGP 4 Multipath Support

The BGP4 Multipath Support feature provides BGP load balancing between multiple Exterior BGP (EBGP) sessions.

Cisco BGP Overview

Cisco IOS XE
Release 2.1

BGP 4 Prefix Filter and In-bound Route Maps

The BGP4 Prefix Filtering with Inbound Route Maps feature allows prefix-based matching support to the inbound neighbor route map. With this addition, an inbound route map can be used to enforce prefix-based policies.

Connecting to a Service Provider Using External BGP

Cisco IOS XE
Release 2.1

BGP 4 Soft Config

The BGP4 Soft Config feature allows BGP4 policies to be configured and activated without clearing the BGP session, hence without invalidating the forwarding cache.

Configuring a Basic BGP Network

Cisco IOS XE
Release 2.1

BGP Conditional Route Injection

The BGP Conditional Route Injection feature allows you to inject more specific prefixes into a BGP routing table over less specific prefixes that were selected through normal route aggregation. These more specific prefixes can be used to provide a finer granularity of traffic engineering or administrative control than is possible with aggregated routes.

Configuring a Basic BGP Network

Cisco IOS XE
Release 2.1

BGP Configuration Using Peer Templates

The BGP Configuration Using Peer Templates feature introduces a new mechanism that groups distinct neighbor configurations for BGP neighbors that share policies. Configuration templates provide an alternative to peer group configuration and overcome some of the limitations of peer groups.

Configuring a Basic BGP Network

Cisco IOS XE
Release 2.1

BGP Convergence Optimization

The BGP Convergence Optimization feature is a new algorithm for update generation that reduces the amount of time that is required for Border Gateway Protocol (BGP) convergence. Neighbor update messages are optimized before they are forwarded to neighbors.

Configuring Advanced BGP Features

Cisco IOS XE
Release 2.1

BGP Cost Community

The BGP Cost Community feature introduces the cost extended community attribute. The cost community is a non-transitive extended community attribute that is passed to internal BGP (iBGP) and confederation peers but not to external BGP (eBGP) peers. The cost community feature allows you to customize the local route preference and influence the best path selection process by assigning cost values to specific routes.

BGP Cost Community

Cisco IOS XE
Release 2.1

BGP Cost Community Support for EIGRP MPLS VPN PE-CE with Backdoor Links

Back door links in an EIGRP MPLS VPN topology will be preferred by BGP if the back door link is learned first. The "pre-best-path" point of insertion (POI) was introduced in the BGP Cost Community feature to support mixed EIGRP VPN network topologies that contain VPN and backdoor links. This POI is applied automatically to EIGRP routes that are redistributed into BGP and the POI influences the best path calculation process by influencing BGP to consider this POI before any other comparison step. No configuration is required. This feature is enabled automatically for EIGRP VPN sites when Cisco IOS XE Release 2.1 or later releases, is installed to a PE, CE, or back door router.

BGP Cost Community

Cisco IOS XE
Release 2.1

BGP Dynamic Update Peer Groups

The BGP Dynamic Update Peer Groups feature introduces a new algorithm that dynamically calculates and optimizes update groups of neighbors that share outbound policies and can share update messages. In previous versions of Cisco IOS software, BGP update messages were grouped based on peer group configurations. This method of grouping updates limited outbound policies and specific-session configurations. The BGP Dynamic Update Peer Groups feature separates update group replication from peer group configuration, which improves convergence time and flexibility of neighbor configuration.

Configuring a Basic BGP Network

Cisco IOS XE
Release 2.1

BGP Graceful Restart per Neighbor

The BGP Graceful Restart per Neighbor feature enables or disables the BGP graceful restart capability for an individual BGP neighbor, including using peer session templates and BGP peer groups.

Configuring Advanced BGP Features

Cisco IOS XE
Release 2.1

BGP Hide Local-Autonomous System

The BGP Hide Local-Autonomous System feature simplifies the task of changing the autonomous system number in a Border Gateway Protocol (BGP) network. Without this feature, this task can be difficult because, during the transition, internal BGP (iBGP) peers will reject external routes from peers with a local autonomous system number in the autonomous system number path to prevent routing loops. This feature allows you to transparently change the autonomous system number for the entire BGP network and ensure that routes can be propagated throughout the autonomous system, while the autonomous system number transition is incomplete.

Configuring BGP Neighbor Session Options

Cisco IOS XE
Release 2.1

BGP Hybrid CLI

The BGP Hybrid CLI feature simplifies the migration of BGP networks and existing configurations from the NLRI format to the AFI format. This new functionality allows the network operator to configure commands in the AFI format and save these command configurations to existing NLRI formatted configurations. The feature provides the network operator with the capability to take advantage of new features and provides support for migration from the NLRI format to the AFI format.

Configuring a Basic BGP Network

Cisco IOS XE
Release 2.1

BGP Increased Support of Numbered AS-Path Access Lists to 500

The BGP Increased Support of Numbered AS-Path Access Lists to 500 feature increases the maximum number of autonomous systems access lists that can be configured using the ip as-path access-list command from 199 to 500.

Connecting to a Service Provider Using External BGP

Cisco IOS XE
Release 2.1

BGP Link Bandwidth

The Border Gateway Protocol (BGP) Link Bandwidth feature is used to advertise the bandwidth of an autonomous system exit link as an extended community. This feature is configured for links between directly connected external BGP (eBGP) neighbors. The link bandwidth extended community attribute is propagated to iBGP peers when extended community exchange is enabled. This feature is used with BGP multipath features to configure load balancing over links with unequal bandwidth.

BGP Link Bandwidth

Cisco IOS XE
Release 2.1

BGP MIB Support Enhancements

The BGP MIB Support Enhancements feature introduced support in the CISCO-BGP4-MIB for new SNMP notifications.

Configuring Advanced BGP Features

Cisco IOS XE
Release 2.1

BGP Multipath Load Sharing for Both eBGP and iBGP in an MPLS VPN

The BGP Multipath Load Sharing for eBGP and iBGP feature allows you to configure multipath load balancing with both external BGP (eBGP) and internal BGP (iBGP) paths in Border Gateway Protocol (BGP) networks that are configured to use Multiprotocol Label Switching (MPLS) Virtual Private Networks (VPNs). This feature provides improved load balancing deployment and service offering capabilities and is useful for multi-homed autonomous systems and Provider Edge (PE) routers that import both eBGP and iBGP paths from multihomed and stub networks.

BGP Multipath Load Sharing for eBGP and iBGP in an MPLs VPN

Cisco IOS XE
Release 2.1

BGP Named Community Lists

The BGP Named Community Lists feature introduces a new type of community list called the named community list. The BGP Named Community Lists feature allows the network operator to assign meaningful names to community lists and increases the number of community lists that can be configured. A named community list can be configured with regular expressions and with numbered community lists. All rules of numbered communities apply to named community lists except that there is no limitation on the number of community attributes that can be configured for a named community list.

Connecting to a Service Provider Using External BGP

Cisco IOS XE
Release 2.1

BGP Neighbor Policy

The BGP Neighbor Policy feature introduces new keywords to two existing commands to display information about local and inherited policies. When BGP neighbors use multiple levels of peer templates, it can be difficult to determine which policies are applied to the neighbor. Inherited policies are policies that the neighbor inherits from a peer-group or a peer-policy template.

Configuring a Basic BGP Network

Cisco IOS XE
Release 2.1

BGP per Neighbor SoO Configuration

The BGP per Neighbor SOO configuration feature simplifies the configuration of the site-of-origin (SoO) parameter. In previous releases, the SoO parameter is configured using an inbound route map that sets the SoO value during the update process. The per neighbor SoO configuration introduces two new commands that can be used under router configuration mode to set the SoO value.

BGP per Neighbor SoO Configuration

Cisco IOS XE
Release 2.1

BGP Next Hop Unchanged

The BGP Next Hop Unchanged feature allows BGP to send an update to an eBGP multihop peer with the next hop attribute unchanged.

BGP Next Hop Unchanged

Cisco IOS XE
Release 2.1

BGP Outbound Route Map to Set IP Next Hop

The BGP Outbound Route Map to Set IP Next Hop feature allows a route reflector to modify the next hop attribute for a reflected route.

Configuring Internal BGP Features

Cisco IOS XE
Release 2.1

BGP Nonstop Forwarding (NSF) Awareness

Nonstop Forwarding (NSF) awareness allows a router to assist NSF-capable neighbors to continue forwarding packets during a Stateful Switchover (SSO) operation. The BGP Nonstop Forwarding Awareness feature allows an NSF-aware router that is running BGP to forward packets along routes that are already known for a router that is performing an SSO operation. This capability allows the BGP peers of the failing router to retain the routing information that is advertised by the failing router and continue to use this information until the failed router has returned to normal operating behavior and is able to exchange routing information. The peering session is maintained throughout the entire NSF operation.

Configuring Advanced BGP Features

Cisco IOS XE
Release 2.1

BGP Policy Accounting

Border Gateway Protocol (BGP) policy accounting measures and classifies IP traffic that is sent to, or received from, different peers. Policy accounting is enabled on an input interface, and counters based on parameters such as community list, autonomous system number, or autonomous system path are assigned to identify the IP traffic.

BGP Policy Accounting Output Interface Accounting

Cisco IOS XE
Release 2.1

BGP Policy Accounting Output Interface Accounting

Border Gateway Protocol (BGP) policy accounting (PA) measures and classifies IP traffic that is sent to, or received from, different peers. Policy accounting was previously available on an input interface only. The BGP Policy Accounting Output Interface Accounting feature introduces several extensions to enable BGP PA on an output interface and to include accounting based on a source address for both input and output traffic on an interface. Counters based on parameters such as community list, autonomous system number, or autonomous system path are assigned to identify the IP traffic.

BGP Policy Accounting Output Interface Accounting

Cisco IOS XE
Release 2.1

BGP Prefix-Based Outbound Route Filtering

The BGP Prefix-Based Outbound Route Filtering feature uses BGP ORF send and receive capabilities to minimize the number of BGP updates that are sent between BGP peers. Configuring this feature can help reduce the number of system resources required for generating and processing routing updates by filtering out unwanted routing updates at the source. For example, this feature can be used to reduce the amount of processing required on a router that is not accepting full routes from a service provider network.

Connecting to a Service Provider Using External BGP

Cisco IOS XE
Release 2.1

BGP Restart Session After Max-Prefix Limit

The BGP Restart Session After Max-Prefix Limit feature enhances the capabilities of the neighbor maximum-prefix command with the introduction of the restart keyword. This enhancement allows the network operator to configure the time interval at which a peering session is reestablished by a router when the number of prefixes that have been received from a peer has exceeded the maximum prefix limit.

Configuring BGP Neighbor Session Options

Cisco IOS XE
Release 2.1

BGP Route-Map Continue

The BGP Route-Map Continue feature introduces the continue clause to BGP route map configuration. The continue clause allows for more programmable policy configuration and route filtering and introduces the capability to execute additional entries in a route map after an entry is executed with successful match and set clauses. Continue clauses allow the network operator to configure and organize more modular policy definitions so that specific policy configurations need not be repeated within the same route map.

Connecting to a Service Provider Using External BGP

Cisco IOS XE
Release 2.1

BGP Route-Map Continue Support for an Outbound Policy

The BGP Route-Map Continue Support for an Outbound Policy feature introduces support for continue clauses to be applied to outbound route maps.

Connecting to a Service Provider Using External BGP

Cisco IOS XE
Release 2.1

BGP Route-Map Policy List Support

The BGP Route-Map Policy List Support feature introduces new functionality to BGP route maps. This feature adds the capability for a network operator to group route map match clauses into named lists called policy lists. A policy list functions like a macro. When a policy list is referenced in a route map, all of the match clauses are evaluated and processed as if they had been configured directly in the route map. This enhancement simplifies the configuration of BGP routing policy in medium-size and large networks because a network operator can preconfigure policy lists with groups of match clauses and then reference these policy lists within different route maps. The network operator no longer needs to manually reconfigure each recurring group of match clauses that occur in multiple route map entries.

Connecting to a Service Provider Using External BGP

Cisco IOS XE
Release 2.1

BGP Selective Address Tracking

The BGP Selective Address Tracking feature introduces the use of a route map for next-hop route filtering and fast session deactivation. Selective next-hop filtering uses a route map to selectively define routes to help resolve the BGP next hop, or a route map can be used to determine if a peering session with a BGP neighbor should be reset when a route to the BGP peer changes.

Configuring Advanced BGP Features

Configuring BGP Neighbor Session Options

Cisco IOS XE
Release 2.1

BGP Support for BFD

Bidirectional Forwarding Detection (BFD) is a detection protocol designed to provide fast forwarding path failure detection times for all media types, encapsulations, topologies, and routing protocols. In addition to fast forwarding path failure detection, BFD provides a consistent failure detection method for network administrators. Because the network administrator can use BFD to detect forwarding path failures at a uniform rate, rather than the variable rates for different routing protocol hello mechanisms, network profiling and planning will be easier, and reconvergence time will be consistent and predictable. The main benefit of implementing BFD for BGP is a significantly faster reconvergence time.

Configuring Advanced BGP Features

Cisco IOS XE
Release 2.1

BGP Support for Dual AS Configuration for Network AS Migrations

The BGP Support for Dual AS Configuration for Network AS Migrations feature extends the functionality of the BGP Local-AS feature by providing additional autonomous-system path customization configuration options. The configuration of this feature is transparent to customer peering sessions, allowing the provider to merge two autonomous-systems without interrupting customer peering arrangements. Customer peering sessions can later be updated during a maintenance window or during other scheduled downtime.

Configuring BGP Neighbor Session Options

Cisco IOS XE
Release 2.1

BGP Support for Fast Peering Session Deactivation

The BGP Support for Fast Peering Session Deactivation feature introduced an event driven notification system that allows a Border Gateway Protocol (BGP) process to monitor BGP peering sessions on a per-neighbor basis. This feature improves the response time of BGP to adjacency changes by allowing BGP to detect an adjacency change and deactivate the terminated session in between standard BGP scanning intervals. Enabling this feature improves overall BGP convergence.

Configuring BGP Neighbor Session Options

Cisco IOS XE
Release 2.1

BGP Support for IP Prefix Import from Global Table into a VRF Table

The BGP Support for IP Prefix Import from Global Table into a VRF Table feature introduces the capability to import IPv4 unicast prefixes from the global routing table into a Virtual Private Network (VPN) routing/forwarding (VRF) instance table using an import route map.

BGP Support for IP Prefix Import from Global Table into a VRF Table

Cisco IOS XE
Release 2.1

BGP Support for Named Extended Community Lists

The BGP Support for Named Extended Community Lists feature introduces the ability to configure extended community lists using names in addition to the existing numbered format.

Connecting to a Service Provider Using External BGP

Cisco IOS XE
Release 2.1

BGP Support for Next-Hop Address Tracking

The BGP Support for Next-Hop Address Tracking feature is enabled by default when a supporting Cisco IOS software image is installed. BGP next-hop address tracking is event driven. BGP prefixes are automatically tracked as peering sessions are established. Next-hop changes are rapidly reported to the BGP routing process as they are updated in the RIB. This optimization improves overall BGP convergence by reducing the response time to next-hop changes for routes installed in the RIB. When a bestpath calculation is run in between BGP scanner cycles, only next-hop changes are tracked and processed.

Configuring Advanced BGP Features

Cisco IOS XE
Release 2.1

BGP Support for Sequenced Entries in Extended Community Lists

The BGP Support for Sequenced Entries in Extended Community Lists feature introduces automatic sequencing of individual entries in BGP extended community lists. This feature also introduces the ability to remove or resequence extended community list entries without deleting the entire existing extended community list.

Connecting to a Service Provider Using External BGP

Cisco IOS XE
Release 2.1

BGP Support for TCP Path MTU Discovery per Session

Border Gateway Protocol (BGP) support for Transmission Control Protocol (TCP) path maximum transmission unit (MTU) discovery introduced the ability for BGP to automatically discover the best TCP path MTU for each BGP session. The TCP path MTU is enabled by default for all BGP neighbor sessions, but you can disable, and subsequently enable, the TCP path MTU globally for all BGP sessions or for an individual BGP neighbor session.

Configuring BGP Neighbor Session Options

Cisco IOS XE
Release 2.1

BGP Support for TTL Security Check

The BGP Support for TTL Security Check feature introduced a lightweight security mechanism to protect external Border Gateway Protocol (eBGP) peering sessions from CPU utilization-based attacks using forged IP packets. Enabling this feature prevents attempts to hijack the eBGP peering session by a host on a network segment that is not part of either BGP network or by a host on a network segment that is not between the eBGP peers.

Configuring BGP Neighbor Session Options

Cisco IOS XE Release 2.1

Configuring internal BGP features

This document describes how to configure internal BGP features. BGP is an interdomain routing protocol that is designed to provide loop-free routing between organizations.

Configuring Internal BGP Features

Cisco IOS XE
Release 2.1

iBGP Multipath Load Sharing

The iBGP Multipath Load Sharing feature enables the BGP speaking router to select multiple iBGP paths as the best paths to a destination. The best paths or multipaths are then installed in the IP routing table of the router.

iBGP Multipath Load Sharing

Cisco IOS XE
Release 2.1

Loadsharing IP Packets Over More Than Six Parallel Paths

The Loadsharing IP Packets Over More Than Six Parallel Paths feature increases the maximum number of parallel routes that can be installed to the routing table for multipath loadsharing.

Loadsharing IP Packets Over More Than Six Parallel Paths

Cisco IOS XE
Release 2.1

Multicast BGP (MBGP)

The Multicast BGP (MBGP) feature adds capabilities to BGP to enable multicast routing policy throughout the Internet and to connect multicast topologies within and between BGP autonomous systems. That is, MBGP is an enhanced BGP that carries IP multicast routes. BGP carries two sets of routes, one set for unicast routing and one set for multicast routing. The routes associated with multicast routing are used by PIM to build data distribution trees.

Cisco BGP Overview

Cisco IOS XE
Release 2.1

Per-VRF Assignment of BGP Router ID

The Per-VRF Assignment of BGP Router ID feature introduces the ability to have VRF-to-VRF peering in Border Gateway Protocol (BGP) on the same router. BGP is designed to refuse a session with itself because of the router ID check. The per-VRF assignment feature allows a separate router ID per VRF using a new keyword in the existing bgp router-id command. The router ID can be manually configured for each VRF or can be assigned automatically either globally under address family configuration mode or for each VRF.

Per-VRF Assignment of BGP Router ID

Cisco IOS XE
Release 2.1

SNMP Support for BGP Policy Accounting

The CISCO-BGP-POLICY-ACCOUNTING-MIB was introduced.

BGP Policy Accounting Output Interface Accounting

Cisco IOS XE
Release 2.1

Suppress BGP Advertisement for Inactive Routes

The Suppress BGP Advertisements for Inactive Routes feature allows you to configure the suppression of advertisements for routes that are not installed in the RIB. Configuring this feature allows BGP updates to be more consistent with data used for traffic forwarding.

Configuring a Basic BGP Network

Cisco IOS XE Release 3S

XE 3.4S

BGP Diverse Path Using a Diverse-Path Route Reflector

The BGP Diverse Path Using a Diverse-Path Route Reflector feature allows BGP to distribute an alternative path other than the best path between BGP speakers when route reflectors are deployed. This feature is meant to provide path diversity within an AS, within a single cluster only. That is, an RR is allowed to advertise the diverse path to its client peers only.

BGP Diverse Path Using a Diverse-Path Route Reflector

XE 3.4S

BGP Enhanced Route Refresh

The BGP Enhanced Route Refresh feature provides a way for Border Gateway Protocol (BGP) to find route inconsistencies, and in that unlikely event, to synchronize BGP peers without a hard reset. The feature is enabled by default; there are two optional timers.

BGP Enhanced Route Refresh

XE 3.3S

BFD for BGP IPv6

Bidirectional Forwarding Detection (BFD) can be used to track fast forwarding path failure of BGP neighbors that have an IPv6 address. BFD is a detection protocol that is designed to provide fast forwarding path failure detection times for all media types, encapsulations, topologies, and routing protocols. BFD provides faster reconvergence time for BGP after a forwarding path failure.

Configuring BGP Neighbor Session Options

XE 3.3S

BGP Consistency Checker

The BGP Consistency Checker feature provides a way to identify certain types of BGP route inconsistencies with peers: next-hop label inconsistency, RIB-out inconsistency, and aggregation inconsistency. Upon finding such an inconsistency, the system sends a syslog error message and optionally takes appropriate action.

Configuring BGP Consistency Checker

XE 3.3S

BGP IPv6 PIC Edge and Core for IP/MPLS

The BGP IPv6 PIC Edge for IP MPLS feature improves convergence after a network failure. This convergence is applicable to both core and edge failures. The BGP IPv6 prefix-independent convergence (PIC) edge for IP MPLS feature creates and stores a backup or alternate path in the routing information base (RIB), forwarding information base (FIB), and in Cisco Express Forwarding, so that when a failure is detected, the backup or lternate path can immediately take over, thus enabling fast failover.

Implementing IPv6 VPN over MPLS

XE 3.3S

BGP Route Server

BGP Route Server is a feature designed for internet exchange (IX) operators that provides an alternative to full eBGP mesh peering among the service providers who have a presence at the IX. The route server provides eBGP route reflection with customized policy support for each service provider. That is, a route server context can override the normal BGP best path for a prefix with a different path based on a policy, or suppress all paths for a prefix and not advertise the prefix. The BGP route server provides reduced configuration complexity and reduced CPU and memory requirements on each border router. The route server also reduces overhead expense incurred by individualized peering agreements.

Configuring BGP Route Server

XE 3.2S

BGP: RT Constrained Route Distribution

BGP: Route Target (RT) Constrained Route Distribution is a feature that service providers can use in MPLS L3VPNs to reduce the number of unnecessary routing updates that route reflectors (RRs) send to RRs and PEs. The reduction in updates saves resources.

BGP: RT Constrained Route Distribution

XE 3.1S

BGP Dynamic Neighbors

BGP dynamic neighbor support allows BGP peering to a group of remote neighbors that are defined by a range of IP addresses. Each range can be configured as a subnet IP address. BGP dynamic neighbors are configured using a range of IP addresses and BGP peer groups. After a subnet range is configured for a BGP peer group and a TCP session is initiated for an IP address in the subnet range, a new BGP neighbor is dynamically created as a member of that group. The new BGP neighbor will inherit any configuration for the peer group.

Configuring BGP Neighbor Session Options

XE 3.1S

BGP—Remove / Replace Private AS

Private autonomous system numbers (ASNs) are used by ISPs and customer networks to conserve globally unique AS numbers. Private AS numbers cannot be used to access the global Internet because they are not unique. AS numbers appear in eBGP AS paths in routing updates. Removing private ASNs from the AS path is necessary if you have been using private ASNs and you want to access the global Internet.

Removing Private AS Numbers from the AS Path in BGP

XE 3.1S

BGP Slow Peer

The BGP Slow Peer feature allows a network administrator to detect a BGP slow peer and also to configure a peer as a slow peer statically or to dynamically mark it. Slow peer detection identifies a peer that is not transmitting update messages within a configured amount of time. Slow peer configuration moves or splits the peer from its normal update group to a slow update group, thus allowing the normal update group to function without being slowed down and to converge quickly.

Detecting and Mitigating a BGP Slow Peer

XE 3.1S

BGP Support for Nonstop Routing (NSR) with Stateful Switchover (SSO) and In-Service Software Upgrade (ISSU)

The BGP Support for Nonstop Routing (NSR) with Stateful Switchover (SSO) feature enables provider edge (PE) routers to maintain BGP state with customer edge (CE) routers and ensure continuous packet forwarding during a Route Processor (RP) switchover or during a planned In-Service Software Upgrade (ISSU) for a PE router.

BGP Support for Nonstop Routing (NSR) with Stateful Switchover (SSO)



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