CCNP BGP iBGP & eBGP BGP NETWORK ADVERTISMENT TWO

Lab related to this topic on youtube: 

Please find playlist in Hindi & English below:https://www.youtube.com/playlist?list=PL1PiPEQOeKMYqOvyKpym_dkoFY2y5BKt0https://www.youtube.com/playlist?list=PL1PiPEQOeKMY3r659R5gyWt4ScTzpyg6w

INTERNAL BGP PEERING(iBGP)

Topology independent

each iBGP speaker must peer with every other iBGP speaker in AS
BGP peer within the same AS
Not required to be direclty connected
iBGP speakers need to be fully meshed they originate connected networks
they do not pass on prefixes learned from other iBGP speakers

EXTERNAL BGP PEERING (eBGP)

Between BGP speakers in different AS
Should be direclty connected
Do not run an IGP between eBGP peers

You can see iBGP relationship and eBGP relationship in the diagram given below.

TWO WAYS TO ADVERTISE BGP NETWORK

A. VIA NETWORK COMMAND
B. VIA REDISTRIBUTION COMMAND


RULES OF BGP 

NO SYNC:

  DO NOT USE OR ADVERTISE A ROUTE LEARNED VIA iBGP UNTIL THE SAME ROUTE WAS LEARNED FROM
THE INTERNAL ROUTING PROTOCOL.

Lab 2: BGP iBGP & eBGP BGP NETWORK ADVERTISMENT

!
hostname R1
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
memory-size iomem 5
ip cef
!
!
!
!
no ip domain lookup
ip auth-proxy max-nodata-conns 3
ip admission max-nodata-conns 3
!
!
!
!
interface Loopback1
 ip address 1.1.1.1 255.255.255.255
!
interface FastEthernet0/0
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface Serial0/0
 ip address 10.1.12.1 255.255.255.252
 clock rate 2000000
!
interface FastEthernet0/1
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface Serial0/1
 no ip address
 shutdown
 clock rate 2000000
!
router ospf 1
 log-adjacency-changes
 network 1.1.1.1 0.0.0.0 area 0
 network 10.1.12.0 0.0.0.3 area 0
!
router bgp 6500
 no synchronization
 bgp log-neighbor-changes
 neighbor 2.2.2.2 remote-as 6500
 neighbor 2.2.2.2 update-source Loopback1
 no auto-summary
!
ip forward-protocol nd
!
line con 0
 exec-timeout 0 0
 logging synchronous
line aux 0
line vty 0 4
 login
!
!
end
------------------------------------------------------------------------------------------------------
!
hostname R2
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
memory-size iomem 5
ip cef
!
!
!
!
no ip domain lookup
ip auth-proxy max-nodata-conns 3
ip admission max-nodata-conns 3
!
!
!
interface Loopback1
 ip address 2.2.2.2 255.255.255.255
!
interface FastEthernet0/0
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface Serial0/0
 ip address 10.1.12.2 255.255.255.252
 clock rate 2000000
!
interface FastEthernet0/1
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface Serial0/1
 ip address 10.1.23.1 255.255.255.252
 clock rate 2000000
!
router ospf 1
 log-adjacency-changes
 network 2.2.2.2 0.0.0.0 area 0
 network 10.1.12.0 0.0.0.3 area 0
!
router bgp 6500
 no synchronization
 bgp log-neighbor-changes
 neighbor 1.1.1.1 remote-as 6500
 neighbor 1.1.1.1 update-source Loopback1
 neighbor 1.1.1.1 next-hop-self
 neighbor 10.1.23.2 remote-as 6501
 no auto-summary
!
ip forward-protocol nd
!
!
no ip http server
no ip http secure-server
!
line con 0
 exec-timeout 0 0
 logging synchronous
line aux 0
line vty 0 4
 login
!
!
end
------------------------------------------------------------------------------------------------
!
hostname R3
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
memory-size iomem 5
ip cef
!
!
!
!
no ip domain lookup
ip auth-proxy max-nodata-conns 3
ip admission max-nodata-conns 3
!
!
interface Loopback1
 ip address 3.3.3.1 255.255.255.255
!
interface Loopback2
 ip address 3.3.3.2 255.255.255.255
!
interface Loopback3
 ip address 3.3.3.3 255.255.255.255
!
interface Loopback4
 ip address 3.3.3.4 255.255.255.255
!
interface FastEthernet0/0
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface Serial0/0
 no ip address
 shutdown
 clock rate 2000000
!
interface FastEthernet0/1
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface Serial0/1
 ip address 10.1.23.2 255.255.255.252
 clock rate 2000000
!
router bgp 6501
 no synchronization
 bgp log-neighbor-changes
 network 3.3.3.1 mask 255.255.255.255
 network 3.3.3.2 mask 255.255.255.255
 redistribute connected route-map forbgp
 neighbor 10.1.23.1 remote-as 6500
 no auto-summary
!
ip forward-protocol nd
!
!
no ip http server
no ip http secure-server
!
ip access-list standard adv
 permit 3.3.3.3
 permit 3.3.3.4
!
!
route-map forbgp permit 10
 match ip address adv
!
route-map forbgp permit 1000
!
!
line con 0
 exec-timeout 0 0
 logging synchronous
line aux 0
line vty 0 4
 login
!
!
end
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