BGP Processes in Cisco Router

BGP Processes:

• BGP Open - responsible for BGP session establishment.
• BGP I/O - handles queuing and processing updates and keep alive packets.
• BGP Scanner - responsible for conditional route advertisements, route dampening, import and export of routes into VRF (MPLS), and confirms the reachability to the NEXT_HOP (the last one is handled now by BGP next-hop tracking).
• BGP Router - calculates the best path, establishes peers, sends and receives routes and interacts with RIB.

BGP command's

router bgp 100

 no synchronization

 bgp log-neighbor-changes

 bgp scan-time 20                

 network 1.1.1.1 mask 255.255.255.255

 timers bgp 5 15

 neighbor 10.1.1.2 remote-as 300

 neighbor 10.2.1.2 remote-as 100

 no auto-summary

Logs

*Mar  1 00:24:00.811: BGP: 10.2.1.2 sending KEEPALIVE (io)

*Mar  1 00:24:00.903: BGP: 10.2.1.2 received KEEPALIVE, length (excl. header) 0

*Mar  1 00:24:01.807: BGP: 10.1.1.2 sending KEEPALIVE (io)

R1#

*Mar  1 00:24:01.895: BGP: 10.1.1.2 received KEEPALIVE, length (excl. header) 0

R1#

*Mar  1 00:25:00.807: BGP: 10.2.1.2 sending KEEPALIVE (io)

*Mar  1 00:25:00.895: BGP: 10.2.1.2 received KEEPALIVE, length (excl. header) 0

*Mar  1 00:25:01.807: BGP: 10.1.1.2 sending KEEPALIVE (io)

R1#

*Mar  1 00:25:01.895: BGP: 10.1.1.2 received KEEPALIVE, length (excl. header) 0

R1#

*Mar  1 00:26:00.807: BGP: 10.2.1.2 sending KEEPALIVE (io)

*Mar  1 00:26:00.911: BGP: 10.2.1.2 received KEEPALIVE, length (excl. header) 0

*Mar  1 00:26:01.807: BGP: 10.1.1.2 sending KEEPALIVE (io)

R1#

*Mar  1 00:26:01.887: BGP: 10.1.1.2 received KEEPALIVE, length (excl. header) 0

R1#

*Mar  1 00:27:00.807: BGP: 10.2.1.2 sending KEEPALIVE (io)

*Mar  1 00:27:00.867: BGP: 10.2.1.2 received KEEPALIVE, length (excl. header) 0

*Mar  1 00:27:01.811: BGP: 10.1.1.2 sending KEEPALIVE (io)

R1#

*Mar  1 00:27:01.891: BGP: 10.1.1.2 received KEEPALIVE, length (excl. header) 0

R1#

*Mar  1 00:28:00.807: BGP: 10.2.1.2 sending KEEPALIVE (io)

*Mar  1 00:28:00.915: BGP: 10.2.1.2 received KEEPALIVE, length (excl. header) 0

*Mar  1 00:28:01.811: BGP: 10.1.1.2 sending KEEPALIVE (io)

R1#

*Mar  1 00:28:01.911: BGP: 10.1.1.2 received KEEPALIVE, length (excl. header) 0

R1#

*Mar  1 00:29:00.807: BGP: 10.2.1.2 sending KEEPALIVE (io)

*Mar  1 00:29:00.903: BGP: 10.2.1.2 received KEEPALIVE, length (excl. header) 0

*Mar  1 00:29:01.807: BGP: 10.1.1.2 sending KEEPALIVE (io)

R1#

*Mar  1 00:29:01.867: BGP: 10.1.1.2 received KEEPALIVE, length (excl. header) 0