Cisco BGP

1.Configuring a BGP Routing Process

1.1 router bgp autonomous-system-number
1.2 network network-number [mask network-mask ] [route-map route-map-name ]
1.3 bgp router-id [ip-address]
1.4 timers bgp [keepalive holdtime]
Use the keepalive argument to specify the frequency, in seconds, with which the software sends keepalive messages to its BGP peer. By default, the keepalive timer is set to 60 seconds.
1.5 (Optional) bgp fast-external-fallover
1.6 bgp log-neighbor-changes
Enables logging of BGP neighbor status changes (up or down) and neighbor resets.

2.Configuring a BGP Peer

2.1 router bgp [autonomous-system-number]
2.2 neighbor [ip-address] remote-as [autonomous-system-number]
2.3 address-family ipv4 [unicast | multicast | vrf vrf-name ]
2.4 neighbor [ip-address] activate

3.Configuring a BGP Peer for the IPv4 VRF Address Family

3.1 ip vrf [vrf-name]
3.2 rd [route-distinguisher]
ex: rd 45000:5
3.3 route-target {import | export | both } route-target-ext-community
ex:route-target both 45000:100
3.4 router bgp [autonomous-system-number]
3.5 address-family ipv4 [unicast | multicast | vrf vrf-name ]
3.6 neighbor [ip-address] remote-as [autonomous-system-number]
3.7 neighbor {ip-address | peer-group-name } maximum-prefix maximum [threshold ] [restart restart-interval ] [warning-only ]
Use the maximum argument to specify the maximum number of prefixes allowed from the specified neighbor. The number of prefixes that can be configured is limited only by the available system resources on a router.
3.8 neighbor [ip-address] activate

4.Customizing(定制) a BGP Peer

no bgp default ipv4-unicast
Disables the IPv4 unicast address family for the BGP routing process.
neighbor {ip-address | peer-group-name } advertisement-interval seconds
(Optional) Sets the minimum interval（时间间隔） between the sending of BGP routing updates.
neighbor {ip-address | peer-group-name } route-map map-name {in | out }
Applies a route map to incoming or outgoing routes.

5.Redistributing a Static Aggregate Route into BGP

5.1 ip route prefix mask {ip-address | interface-type interface-number [ip-address ]} [distance ] [name ] [permanent | track number ] [tag tag ]
5.2 router bgp autonomous-system-number
5.3 redistribute static

Cisco BGP reference