How to configure BGP peer-group ?

router bgp YY

no synchronization

no auto-summary

neighbor IBGP peer-group                    \\\\ where IBGP is the peer group name and can be kept as per you need..

neighbor IBGP remote-as YY                \\\\  YY - we define what AS does the peer group belong to

neighbor IBGP update-source Loopback0 - wise to do it this way  ... safe if you have a physical link faliure.

neighbor IBGP route-reflector-client  \\\\ if ithe router is a RR

neighbor IBGP send-community          \\\\ if there are communities.

neighbor YY.YY.1.1 peer-group IBGP   |

neighbor YY.YY.2.2 peer-group IBGP   |______  these all are the neighbors that belong to this peer group

neighbor YY.YY.3.3 peer-group IBGP   |

neighbor YY.YY.5.5 peer-group IBGP   |

I hope that is Quite Clear.

Once a peer group is created with the neighbor peer-group command, it can be configured with the neighbor commands.

Router (config) # router bgp as-number

Creating the Peer-Group

Router(config-router)# neighbor peer-group-name peer-group

Specify BGP neighbor Router

(config-router) # neighbor ip-address or peer-group-name remote-as as-number

Peer-group configuration

Router (config) # neighbor ip-address peer-group peer-group-name