BGP4 Peer Groups

You can associate neighbor IPv4 addresses with a peer group. All of the attributes that are allowed on a neighbor are also allowed on a peer group. The benefits of peer groups are:

Simplified neighbor configuration. You can configure a set of neighbor parameters and then apply them to multiple neighbors. You do not need to configure the common parameters individually on each neighbor.
Flash memory conservation. Using peer groups instead of individually configuring all the parameters for each neighbor requires fewer configuration commands in the startup configuration file.

You can perform the following tasks for a peer group.

Reset neighbor sessions
Perform soft-outbound resets, in which the device updates outgoing route information to neighbors but does not entirely reset the sessions with those neighbors
Clear BGP4 message statistics
Clear error buffers

An attribute value configured for a neighbor takes precedence over the attribute value configured for a peer group. The default attribute is used if the neither the peer group nor the neighbor has the attribute configured.

For the parameters of a BGP4 peer group to take effect, you must activate the peer group in IPv4 unicast address family configuration mode.