创建完bgp peer之后，就要bgp start了，不然费那么大劲创建出来不做事情就销毁了，就很尴尬了。
那么对等体一旦start起来，就会进入各自的状态，在不同的状态下处理各自的事件消息。
下面列举一些状态和事件的集合：
1 /* BGP finite state machine status. */ 2 #define Idle 1 3 #define Connect 2 4 #define Active 3 5 #define OpenSent 4 6 #define OpenConfirm 5 7 #define Established 6 8 #define Clearing 7 9 #define Deleted 8 10 #define BGP_STATUS_MAX 9 11 12 /* BGP finite state machine events. */ 13 #define BGP_Start 1 14 #define BGP_Stop 2 15 #define TCP_connection_open 3 16 #define TCP_connection_closed 4 17 #define TCP_connection_open_failed 5 18 #define TCP_fatal_error 6 19 #define ConnectRetry_timer_expired 7 20 #define Hold_Timer_expired 8 21 #define KeepAlive_timer_expired 9 22 #define Receive_OPEN_message 10 23 #define Receive_KEEPALIVE_message 11 24 #define Receive_UPDATE_message 12 25 #define Receive_NOTIFICATION_message 13 26 #define Clearing_Completed 14 27 #define BGP_EVENTS_MAX 15
原文：http://www.cnblogs.com/danxi/p/6349228.html