8-22 . neighbor {ip-address | peer-group-name} prefix-list prefix-list-name out

Syntax Description:

  • ip-address— Neighbor's IP address.

  • peer-group-name— Name of the peer group. See section 8-19.

  • prefix-list-name— Name of the output IP prefix list.

Purpose: To filter outgoing route updates to a particular BGP neighbor based on the IP address and mask length. Only one prefix list can be used per neighbor. The operation of the output prefix list is identical for both IBGP and EBGP neighbors. Using a prefix list is an alternative to using an extended IP access list and a distribution list.

Cisco IOS Software Release: 12.0

Configuration Example 1: Allow an Aggregate Route While Blocking the More-Specific Routes

In Figure 8-21, Router B is advertising ...

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