Routing – Routers are not learning routes when using RIP

riprouting

I am trying to implement simple scenario of RIP using Packet Tracer, first of all here is the scenario.

and I have used the following commands to configure RIPv2 in each router,

R1:

router rip
version 2
network 172.30.10.0
network 10.1.1.0
no auto-summary

R2

router rip
version 2
network 10.1.1.0
network 10.2.2.0
no auto-summary

R3

router rip
version 2
network 172.30.30.0
network 10.2.2.0

Now if i see the output of show ip route command on R1, it doesn't show any route to 172.30.0.0 subnet of R3,

     10.0.0.0/30 is subnetted, 1 subnets
C       10.1.1.0 is directly connected, Serial0/1/0
     172.30.0.0/24 is subnetted, 1 subnets
C       172.30.10.0 is directly connected, FastEthernet0/0

Similarly, here are the outputs of R2 and R3

R2,

     10.0.0.0/30 is subnetted, 2 subnets
C       10.1.1.0 is directly connected, Serial0/1/0
C       10.2.2.0 is directly connected, Serial0/1/1
     172.30.0.0/24 is subnetted, 1 subnets
R       172.30.10.0 [120/1] via 10.1.1.1, 00:00:19, Serial0/1/0

R2 only learned the path to 172.30.10.0 network on R1 but not the path of the subnetworks in R3.

R3

     10.0.0.0/24 is subnetted, 1 subnets
C       10.2.2.0 is directly connected, Serial0/1/1
     172.30.0.0/24 is subnetted, 1 subnets
C       172.30.30.0 is directly connected, FastEthernet0/0

I don't know what am I missing.
I read on other post that I was supposed to disable auto-summary in each router which I have already did, and I have also clear the routing table after that but it is not working either.

Best Answer

You are missing no auto-summary in R3. If that does not solve the problem maybe you need to issue the 'IP routing' command in each router.

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The update-source isn't used for eBGP unless you use eBGP multihop (which you aren't), and it's unnecessary for your iBGP since you are not sourcing from a different interface from the one which you are using to connect the neighbors. You should remove those lines.

You don't seem to be using communities, so you can lose the lines with send-community both. Normally you would have consistent communities on prefixes within your AS, and you would only use that when you need to send your communities to a different AS.

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I think your BGP configurations should look something like:

R101:

router bgp 1
 no synchronization
 bgp router-id 0.0.0.1
 bgp log-neighbor-changes
! network 1.0.0.0
! network 2.0.0.0
 aggregate-address 1.1.1.0 255.255.255.0 summary-only
 aggregate-address 2.2.2.0 255.255.255.0 summary-only
 neighbor 4.4.4.1 remote-as 2
 neighbor 4.4.4.1 description "R101 uplink"
 neighbor 4.4.4.1 update-source 4.4.4.2
 neighbor 4.4.4.1 route-map R1-MAP out
 neighbor 4.4.4.1 soft-reconfiguration inbound
 neighbor 1.1.1.2 remote-as 1
 neighbor 1.1.1.2 description "R101 BGP interconnect"
 neighbor 1.1.1.2 next-hop-self
 maximum-paths 2
 no auto-summary
!

R102:

router bgp 1
 no synchronization
 bgp router-id 0.0.0.2
 bgp log-neighbor-changes
! network 1.0.0.0
! network 2.0.0.0
 aggregate-address 1.1.1.0 255.255.255.0 summary-only
 aggregate-address 2.2.2.0 255.255.255.0 summary-only
 neighbor 3.3.3.1 remote-as 2
 neighbor 3.3.3.1 description "R102 uplink"
 neighbor 3.3.3.1 update-source 3.3.3.2
 neighbor 3.3.3.1 route-map R102-MAP out
 neighbor 3.3.3.1 soft-reconfiguration inbound
 neighbor 1.1.1.1 remote-as 1
 neighbor 1.1.1.1 description "R102 BGP interconnect"
 neighbor 1.1.1.1 next-hop-self
 no auto-summary
!

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