Cisco® BGP-4 Command and Configuration Handbook (CCIE Professional Development)

1-1. aggregate-address address mask

Syntax Description:

• address— Aggregate IP address.

• mask— Aggregate mask.

Purpose: To create an aggregate entry in the BGP table. An aggregate is created only if a more-specific route of the aggregate exists in the BGP table. This form of the aggregate-address command advertises the aggregate and all the more-specific routes that are part of the aggregate.

Cisco IOS Software Release: 10.0

Configuration Example 1: Aggregating Local Routes

For this example, we will aggregate locally sourced routes. In Figure 1-1, Router B aggregates the four networks 172.16.0.x through 172.16.3.x.

Figure 1-1. Aggregating Locally Sourced Routes

Router A
router bgp 1
neighbor 10.1.1.2 remote-as 2
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