BGP Configuration Guidelines

To configure the Border Gateway Protocol (BGP), you can include statements at the [edit protocols bgp] hierarchy level in the configuration. Three portions of the bgp statement—the portions in which you configure global BGP, group-specific, and peer-specific options—contain many of the same statements. The following simplified version of the bgp statement omits these repeated statements to present a high-level, readable overview:

protocols {

    bgp { 

        numerous global BGP statements

        group group-name { 

            peer-as autonomous-system ;

            type type ; 

            allow [ network/mask-length  ]; 

            numerous group-specific statements 

            neighbor address {

                numerous peer-specific statements 

            }

        } 

    }

} 

For a list of global BGP statements, see Define BGP Global Properties. For a list of group-specific statements, see Define Group Properties. For a list of peer-specific statements, see Define Peer Properties.

Many of the global BGP, group-specific, and peer-specific statements are identical. For statements that you can configure at more than one level in the hierarchy, the more-specific statement overrides the less-specific statement. That is, a group-specific statement overrides a global BGP statement, and a peer-specific statement overrides a global BGP or group-specific statement.

By default, BGP is disabled.

This chapter describes the following tasks for configuring BGP:

• Minimum BGP Configuration
• Enable BGP
• Modify the Hold-Time Value
• Configure Authentication
• Apply an IPSec Security Association
• Open a Peer Connection Passively
• Configure the Local IP Address
• Configure the Multiple Exit Discriminator Metric
• Control the Aggregator Path Attribute
• Choose the Protocol Used to Determine the Next Hop
• Configure an EBGP Multihop Session
• Configure the BGP Local Preference
• Control Route Preference
• Configure Routing Table Path Selection
• Configure BGP to Select Multiple BGP Paths
• Configure a Local AS
• Remove Private AS Numbers from AS Paths
• Configure Route Reflection
• Enable Route Flap Damping
• Enable Multiprotocol BGP
• Configure BGP Routing Policy
• Configure IPv6 BGP Routes over IPv4 Transport
• Configure BGP to Log System Log Messages
• Describe BGP Router Configuration
• Trace BGP Protocol Traffic