Packet Tracer 5.3 - BGP configuration

BGP in Packet Tracer

BGP (Border Gateway Protocol) is the core routing protocol of the Internet. It is described as a path vector protocol as BGP does not use traditional IGP (OSPF, EIGRP, RIP) metrics, but makes routing decisions based on path, network policies and/or rulesets. It maintains a table of IP networks or 'prefixes' which designate network reachability among autonomous systems (AS).

BGP protocol support has been added in Packet Tracer in the 5.3 version. This allows Cisco CCNP Route students to better understand this complex routing protocol and to be prepared for the simulation questions in the exam.

Internal BGP (iBGP) is currently not supported in Packet Tracer (see screenshot below).

IOS commands available in Packet Tracer 5.3

enable mode

• show ip bgp
• show ip bgp neighbors
• show ip bgp summary
• clear ip bgp *

router bgp mode

• log-neighbor-changes
• redistribute-internal
• router-id A.B.C.D
• exit
• neighbor A.B.C.D next-hop-self
• neighbor A.B.C.D remote-as <1-65535>
• network A.B.C.D
• network A.B.C.D mask A.B.C.D
• redistribute connected / eigrp <1-65535> / ospf <1-65535> / static
• synchronization
• timers bgp <0-65535> <0-65535>

Sample BGP network

Router WAN1 configuration  :

interface Serial0/0/0
ip address 156.12.1.6 255.255.255.252
!
router bgp 65000
bgp log-neighbor-changes
no synchronization
neighbor 156.12.1.5 remote-as 10000

Router ISP1 configuration :

interface Loopback0
ip address 156.100.1.1 255.255.255.0
!
interface Loopback1
ip address 156.100.2.1 255.255.255.0
!
interface Loopback2
ip address 156.100.4.1 255.255.254.0
!
interface Serial0/0/0
ip address 156.12.1.5 255.255.255.252
clock rate 500000
!
router bgp 10000
bgp log-neighbor-changes
no synchronization
neighbor 156.12.1.6 remote-as 65000
network 156.100.4.0 mask 255.255.254.0
network 156.100.2.0 mask 255.255.255.0
network 156.100.1.0 mask 255.255.255.0
!