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a question with BGP loopback neighbor establishement

hello,

i have 2 routers on GNS3, i want to configure BGP based on the loopback of each router, but it never comes to Established status, it is stuck in "Active" here is my topology:


                               R1 =================
                                                                   //================== R2

Config:

R1:

R1#show run
Building configuration...

Current configuration : 1048 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R1
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
memory-size iomem 5
!
!
ip cef
no ip domain lookup
!
!
!
!        
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
interface Loopback1
 ip address 1.1.1.1 255.255.255.0
!        
interface Serial0/0
 ip address 192.168.12.1 255.255.255.0
 serial restart-delay 0
!
interface Serial0/1
 no ip address
 shutdown
 serial restart-delay 0
!
interface Serial0/2
 no ip address
 shutdown
 serial restart-delay 0
!
interface Serial0/3
 no ip address
 shutdown
 serial restart-delay 0
!
router bgp 1
 no synchronization
 bgp router-id 1.1.1.1
 bgp log-neighbor-changes
 network 192.168.12.0
 neighbor 2.2.2.2 remote-as 2
 neighbor 2.2.2.2 ebgp-multihop 2
 neighbor 2.2.2.2 update-source Loopback1
 no auto-summary
!
no ip http server
no ip http secure-server
!
!
!
!
!
!
control-plane
!
!
!
!
!
!
!
!        
!
!
line con 0
 exec-timeout 0 0
 logging synchronous
line aux 0
line vty 0 4
!
!
end

R1#

=================================================================


R2:

R2#show run
Building configuration...

Current configuration : 1048 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R2
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
memory-size iomem 5
!
!
ip cef
no ip domain lookup
!
!
!
!        
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
interface Loopback1
 ip address 2.2.2.2 255.255.255.0
!        
interface Serial0/0
 ip address 192.168.12.2 255.255.255.0
 serial restart-delay 0
!
interface Serial0/1
 no ip address
 shutdown
 serial restart-delay 0
!
interface Serial0/2
 no ip address
 shutdown
 serial restart-delay 0
!
interface Serial0/3
 no ip address
 shutdown
 serial restart-delay 0
!
router bgp 2
 no synchronization
 bgp router-id 2.2.2.2
 bgp log-neighbor-changes
 network 192.168.12.0
 neighbor 1.1.1.1 remote-as 1
 neighbor 1.1.1.1 ebgp-multihop 2
 neighbor 1.1.1.1 update-source Loopback1
 no auto-summary
!
no ip http server
no ip http secure-server
!
!
!
!
!
!
control-plane
!
!
!
!
!
!
!
!        
!
!
line con 0
 exec-timeout 0 0
 logging synchronous
line aux 0
line vty 0 4
!
!
end

R2#

0
zakar1a
Asked:
zakar1a
  • 3
  • 3
1 Solution
 
Ken BooneNetwork ConsultantCommented:
The problem is that either router does not have a route to the other's BGP loopback address.  You have to be able to at least reach your BGP peer and right now you cannot.  Add a static route on each router to reach the other's BGP peer ip address and then it should come up.
0
 
zakar1aAuthor Commented:
i got this from debug:


*Mar  1 01:24:06.947: BGP: 2.2.2.2 active open failed - no route to peer, open active delayed 26593ms (35000ms max, 28% jitter)
0
 
Ken BooneNetwork ConsultantCommented:
That is exactly what I mean:

On rtr 1 you need:
ip route 2.2.2.2 255.255.255.0 192.168.12.2

On rtr 2 you need:
ip route 1.1.1.1 255.255.255.0 192.168.12.1

Then each router will have a route to the other's loopback and then it will come up.
0
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zakar1aAuthor Commented:
you meant :

ip route 2.2.2.2 255.255.255.255 192.168.12.2
ip route 1.1.1.1 255.255.255.255 192.168.12.1

right?
0
 
Ken BooneNetwork ConsultantCommented:
yea correct.
0
 
zakar1aAuthor Commented:
thank you
0

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