CCNP Routing and Switching ROUTE 300-101 Official Cert Guide

Peer Groups

Lesson 7: BGP Peer Groups

Cisco IOS creates BGP updates, by default, on a neighbor-by-neighbor basis. As a result, more neighbors result in more CPU resources being used. Also, by applying nondefault settings (for example, performing filtering using prefix lists, route maps, or filter lists) to those neighbors, even more CPU resources are required.

However, many neighbors might have similarly configured parameters. Cisco IOS allows you to logically group those similar neighbors into a BGP peer group. Then, you can apply your nondefault BGP configuration to the peer group, as opposed to applying those parameters to each neighbor individually. ...