R1
                                    |  
                                       RIP
                                    |
                                   R2
                                    |
                                       EIGRP
                                    |
                                   R3
R1#show running-config
!
hostname R1
interface Loopback0
 ip address 10.0.0.1 255.0.0.0
!
interface Serial1/1
 ip address 20.0.0.1 255.0.0.0
 serial restart-delay 0
!
router rip
 network 10.0.0.0
 network 20.0.0.0
 default-information originate
!
ip route 0.0.0.0 0.0.0.0 20.0.0.2
no ip http server
no ip http secure-server
!

R2#show running-config
hostname R2
!
interface Serial1/0
 ip address 20.0.0.2 255.0.0.0
 serial restart-delay 0
!
interface Serial1/1
 ip address 30.0.0.1 255.0.0.0
 serial restart-delay 0
!
router eigrp 90
 network 20.0.0.0
 network 30.0.0.0
 auto-summary
!
ip default-network 20.0.0.0
ip route 0.0.0.0 0.0.0.0 20.0.0.1
no ip http server
no ip http secure-server
!

R3#show running-config
!
hostname R3
!
interface Loopback0
 ip address 40.0.0.1 255.0.0.0

!
interface Serial1/0
 ip address 30.0.0.2 255.0.0.0
 serial restart-delay 0
!
router eigrp 90
 network 30.0.0.0
 network 40.0.0.0
 auto-summary

 

 

R1#show ip rou
Gateway of last resort is 20.0.0.2 to network 0.0.0.0

C    20.0.0.0/8 is directly connected, Serial1/1
C    10.0.0.0/8 is directly connected, Loopback0
S*   0.0.0.0/0 [1/0] via 20.0.0.2

R2#show ip rou
Gateway of last resort is 20.0.0.1 to network 0.0.0.0

C*   20.0.0.0/8 is directly connected, Serial1/0
D    40.0.0.0/8 [90/2297856] via 30.0.0.2, 00:00:48, Serial1/1
C    30.0.0.0/8 is directly connected, Serial1/1
S*   0.0.0.0/0 [1/0] via 20.0.0.1

R3#show ip rou
Gateway of last resort is 30.0.0.1 to network 20.0.0.0

D*   20.0.0.0/8 [90/2681856] via 30.0.0.1, 00:01:04, Serial1/0
C    40.0.0.0/8 is directly connected, Loopback0
C    30.0.0.0/8 is directly connected, Serial1/0