ip-address— Neighbor's IP address.
peer-group-name— Name of the peer group. See section 8-19.
Purpose: IBGP neighbors do not propagate routing information learned from one IBGP neighbor to another IBGP neighbor. Therefore, if you are running IBGP, every IBGP speaker must have a connection to every other IBGP speaker in the AS. This becomes a scaling problem as the number of IBGP speakers increases. The number of IBGP connections for n speakers is (n(n-1))/2. Table 8-1 lists the number of connections needed for 2 to 10 IBGP speakers.
|Number of IBGP Speakers||Number of Connections|