RIPv2 Network Summarization Configuration on Cisco Routers

Objective

Understand automatic network summarization using Routing Information Protocol version 2 (RIPv2) on a Cisco IOS router. Learn to prevent automatic summarization at default network boundaries.

Purpose

Mastering RIPv2 configuration is essential for network engineers. Learn to enable RIPv2, disable automatic summarization, and manage VLSM in modern networks. This knowledge is critical for Cisco engineers and CCNA exam candidates.

Lab Topology

Use the following topology to complete this lab exercise:

Image 1

Task 1: Configure Hostnames

Objective: Set the hostnames on R1, R2, R3, and SW1 as shown in the topology.

Configuration:

R1#configure terminal
R1(config)#hostname R1
R1(config)#end

R2#configure terminal
R2(config)#hostname R2
R2(config)#end

R3#configure terminal
R3(config)#hostname R3
R3(config)#end
R3#

SW1#configure terminal
SW1(config)#hostname SW1
SW1(config)#end
SW1#

Task 2: Configure VLAN and Interfaces

Objectives:

  1. Configure VLAN2 named RIPv2-VLAN on Sw2.
  2. Assign ports FastEthernet0/1 and FastEthernet0/2 to this VLAN as access ports.
  3. Configure FastEthernet0/0 in R2 with IP 192.168.2.2/27 and FastEthernet0/0 on R3 with IP 192.168.2.3/27.
  4. Verify VLAN and interface configuration using ping.

Configuration:

w2#configure terminal
Sw2(config)#vlan 2
Sw2(config-vlan)#name RIPv2-VLAN
Sw2(config-vlan)#exit
Sw2(config)#interface FastEthernet0/1
Sw2(config-if)#switchport mode access
Sw2(config-if)#switchport access vlan 2
Sw2(config-if)#exit
Sw2(config)#interface FastEthernet0/2
Sw2(config-if)#switchport mode access
Sw2(config-if)#switchport access vlan 2
Sw2(config-if)#end
Sw2#

R2#configure terminal
R2(config)#interface FastEthernet0/0
R2(config-if)#ip address 192.168.2.2 255.255.255.224
R2(config-if)#no shutdown
R2(config-if)#end
R2#

R3#configure terminal
R3(config)#interface FastEthernet0/0
R3(config-if)#ip address 192.168.2.3 255.255.255.224
R3(config-if)#no shutdown
R3(config-if)#end
R3#

Task 3: Configure Serial Connections

Objectives:

  1. Establish a back-to-back Serial connection between R1 and R2.
  2. Set the DCE interface Serial0/0/0 in R2 to provide clocking to R1 at 128 Kbps.
  3. Configure a back-to-back Serial connection between R2 and R3.
  4. Set the DCE interface Serial0/0/1 in R2 to provide clocking to R3 at 128 Kbps.
  5. Configure the IP addresses as illustrated in the topology.
  6. Validate configuration by pinging between R1, R2, and R3.

Configuration:

R2#configure terminal
R2(config)#interface Serial0/0/0
R2(config-if)#clock rate 128000
R2(config-if)#ip address 192.168.0.2 255.255.255.252
R2(config-if)#no shutdown
R2(config-if)#end
R2#

R1#configure terminal
R1(config)#interface Serial0/0/0
R1(config-if)#ip address 192.168.0.1 255.255.255.252
R1(config-if)#no shutdown
R1(config-if)#end
R1#

R2#configure terminal
R2(config)#interface Serial0/0/1
R2(config-if)#clock rate 128000
R2(config-if)#ip address 192.168.1.2 255.255.255.252
R2(config-if)#no shutdown
R2(config-if)#end
R2#

R3#configure terminal
R3(config)#interface Serial0/0/0
R3(config-if)#ip address 192.168.1.1 255.255.255.252
R3(config-if)#no shutdown
R3(config-if)#end


R1#ping 192.168.0.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.0.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 6/11/18 ms

R1#ping 192.168.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 16/25/33 ms

R2#ping 192.168.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 11/15/26 ms

Task 4: Configure Loopback Interfaces

Objective: Configure the Loopback interfaces on R1 and R3 as specified in the topology.

Configuration:

R1#conf t
R1(config)#int loopback100
R1(config-if)#ip address 10.10.100.1 255.255.255.224
R1(config)#int loopback101
R1(config-if)#ip address 10.10.101.1 255.255.255.192

R3#conf t
R3(config)#int loopback100
R3(config-if)#ip address 10.30.100.1 255.255.255.248
R3(config)#int loopback101
R3(config-if)#ip address 10.30.101.1 255.255.255.128

Task 5: Enable RIPv2

Objective: Enable RIPv2 on R1, R2, and R3 for all subnets. Verify RIPv2 using the appropriate commands.

Configuration:

R3#conf t
R3(config)#router rip
R3(config-router)#version 2
R3(config-router)#network 10.0.0.0
R3(config-router)#network 192.168.1.0
R3(config-router)#network 192.168.2.0
R3(config-router)#end

R3#show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 17 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
  Interface             Send  Recv  Triggered RIP  Key-chain
  Loopback100           22
  Loopback101           22
  FastEthernet0/0       22
  Serial0/0/0           22
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
	10.0.0.0
	192.168.1.0
	192.168.2.0
Passive Interface(s):
Routing Information Sources:
	Gateway         Distance      Last Update
	192.168.1.2          120      00:00:07
	192.168.2.2          120      00:00:07
Distance: (default is 120)

R2#conf t
R2(config)#router rip
R2(config-router)#version 2
R2(config-router)#network 192.168.0.0
R2(config-router)#network 192.168.1.0
R2(config-router)#network 192.168.2.0
R2(config-router)#end

R2#show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 7 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
  Interface             Send  Recv  Triggered RIP  Key-chain
  FastEthernet0/0       22
  Serial0/0/0           22
  Serial0/0/1           22
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
	192.168.0.0
	192.168.1.0
	192.168.2.0
Passive Interface(s):
Routing Information Sources:
	Gateway         Distance      Last Update
	192.168.2.3          120      00:00:22
	192.168.0.1          120      00:00:24
	192.168.1.1          120      00:02:38
Distance: (default is 120)

R1#conf t
R1(config)#router rip
R1(config-router)#version 2
R1(config-router)#network 10.0.0.0
R1(config-router)#network 192.168.0.0
R1(config-router)#end

R1#show ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds, next due in 1 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive 2
  Interface             Send  Recv  Triggered RIP  Key-chain
  Serial0/0/0           22
  Loopback100           22
  Loopback101           22
Automatic network summarization is in effect
Maximum path: 4
Routing for Networks:
	10.0.0.0
	192.168.0.0
Passive Interface(s):
Routing Information Sources:
	Gateway         Distance      Last Update
	192.168.0.2          120      00:00:23
Distance: (default is 120)

Task 6: Verify Routing Tables

Check the routing tables of R1, R2, and R3 to verify the presence of specific routes. Ensure only a 10.0.0.0/8 subnet is visible due to automatic summarization.

R1#sh ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
       i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
       * - candidate default, U - per-user static route, o - ODR
       P - periodic downloaded static route

Gateway of last resort is not set

     10.0.0.0/8 is variably subnetted, 3 subnets, 3 masks
R       10.0.0.0/8 [120/2] via 192.168.0.2, 00:00:03, Serial0/0/0
C       10.10.100.0/27 is directly connected, Loopback100
C       10.10.101.0/26 is directly connected, Loopback101
     192.168.0.0/24 is variably subnetted, 2 subnets, 2 masks
R       192.168.0.0/24 is possibly down, routing via 192.168.0.2, Serial0/0/0
C       192.168.0.0/30 is directly connected, Serial0/0/0
R    192.168.1.0/24 is possibly down, routing via 192.168.0.2, Serial0/0/0
R    192.168.2.0/24 is possibly down, routing via 192.168.0.2, Serial0/0/0

R2#sh ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
       i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
       * - candidate default, U - per-user static route, o - ODR
       P - periodic downloaded static route

Gateway of last resort is not set

R    10.0.0.0/8 [120/1] via 192.168.0.1, 00:00:13, Serial0/0/0
                [120/1] via 192.168.1.1, 00:00:25, Serial0/0/1
                [120/1] via 192.168.2.3, 00:00:25, FastEthernet0/0
     192.168.0.0/24 is variably subnetted, 2 subnets, 2 masks
R       192.168.0.0/24 is possibly down, routing via 192.168.1.1, Serial0/0/1
                       is possibly down, routing via 192.168.2.3, FastEthernet0/0
C       192.168.0.0/30 is directly connected, Serial0/0/0
     192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks
R       192.168.1.0/24 is possibly down, routing via 192.168.1.1, Serial0/0/1
C       192.168.1.0/30 is directly connected, Serial0/0/1
     192.168.2.0/24 is variably subnetted, 2 subnets, 2 masks
R       192.168.2.0/24 is possibly down, routing via 192.168.2.3, FastEthernet0/0
C       192.168.2.0/27 is directly connected, FastEthernet0/0
R3#sh ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
       i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
       * - candidate default, U - per-user static route, o - ODR
       P - periodic downloaded static route

Gateway of last resort is not set

     10.0.0.0/8 is variably subnetted, 3 subnets, 3 masks
R       10.0.0.0/8 [120/2] via 192.168.2.2, 00:01:23, FastEthernet0/0
                   [120/2] via 192.168.1.2, 00:01:23, Serial0/0/0
C       10.30.100.0/29 is directly connected, Loopback100
C       10.30.101.0/25 is directly connected, Loopback101
R    192.168.0.0/24 [120/1] via 192.168.2.2, 00:00:21, FastEthernet0/0
                    [120/1] via 192.168.1.2, 00:00:21, Serial0/0/0
     192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks
R       192.168.1.0/24 is possibly down, routing via 192.168.1.2, Serial0/0/0
C       192.168.1.0/30 is directly connected, Serial0/0/0
     192.168.2.0/24 is variably subnetted, 2 subnets, 2 masks
R       192.168.2.0/24 is possibly down, routing via 192.168.2.2, FastEthernet0/0
C       192.168.2.0/27 is directly connected, FastEthernet0/0

Task 7: Disable Automatic Summarization

Objective: Disable automatic summarization on R1, R2, and R3. Reset routing tables with the command: clear ip route *.

Configuration:

R1#conf t
R1(config)#router rip
R1(config-router)#no auto-summary
R1(config-router)#end

R2#conf t
R2(config)#router rip
R2(config-router)#no auto-summary
R2(config-router)#end

R3#conf t
R3(config)#router rip
R3(config-router)#no auto-summary
R3(config-router)#end

R1#clear ip route *
R1#copy running-config startup-config

R2#clear ip route *
R2#copy running-config startup-config

R3#clear ip route *
R3#copy running-config startup-config

Task 8: Verify Updated Routing Tables

Objective: Check routing tables of R2 and R3 for 10.10.100.0/27 and 10.10.101.0/26 routes from R1. Check R1 and R2 for 10.30.100.0/29 and 10.30.101.0/25 routes from R3.

R1#sh ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
       i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
       * - candidate default, U - per-user static route, o - ODR
       P - periodic downloaded static route

Gateway of last resort is not set

     10.0.0.0/8 is variably subnetted, 4 subnets, 4 masks
C       10.10.100.0/27 is directly connected, Loopback100
C       10.10.101.0/26 is directly connected, Loopback101
R       10.30.100.0/29 [120/2] via 192.168.0.2, 00:00:17, Serial0/0/0
R       10.30.101.0/25 [120/2] via 192.168.0.2, 00:00:17, Serial0/0/0
     192.168.0.0/30 is subnetted, 1 subnets
C       192.168.0.0 is directly connected, Serial0/0/0
     192.168.1.0/30 is subnetted, 1 subnets
R       192.168.1.0 [120/1] via 192.168.0.2, 00:00:18, Serial0/0/0
     192.168.2.0/27 is subnetted, 1 subnets
R       192.168.2.0 [120/1] via 192.168.0.2, 00:00:18, Serial0/0/0

R2#sh ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
       i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
       * - candidate default, U - per-user static route, o - ODR
       P - periodic downloaded static route

Gateway of last resort is not set

     10.0.0.0/8 is variably subnetted, 4 subnets, 4 masks
R       10.10.100.0/27 [120/1] via 192.168.0.1, 00:00:11, Serial0/0/0
R       10.10.101.0/26 [120/1] via 192.168.0.1, 00:00:11, Serial0/0/0
R       10.30.100.0/29 [120/1] via 192.168.2.3, 00:00:20, FastEthernet0/0
                       [120/1] via 192.168.1.1, 00:00:20, Serial0/0/1
R       10.30.101.0/25 [120/1] via 192.168.2.3, 00:00:20, FastEthernet0/0
                       [120/1] via 192.168.1.1, 00:00:20, Serial0/0/1
     192.168.0.0/30 is subnetted, 1 subnets
C       192.168.0.0 is directly connected, Serial0/0/0
     192.168.1.0/30 is subnetted, 1 subnets
C       192.168.1.0 is directly connected, Serial0/0/1
     192.168.2.0/27 is subnetted, 1 subnets
C       192.168.2.0 is directly connected, FastEthernet0/0

R3#sh ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
       i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
       * - candidate default, U - per-user static route, o - ODR
       P - periodic downloaded static route

Gateway of last resort is not set

     10.0.0.0/8 is variably subnetted, 4 subnets, 4 masks
R       10.10.100.0/27 [120/2] via 192.168.2.2, 00:00:11, FastEthernet0/0
                       [120/2] via 192.168.1.2, 00:00:11, Serial0/0/0
R       10.10.101.0/26 [120/2] via 192.168.2.2, 00:00:11, FastEthernet0/0
                       [120/2] via 192.168.1.2, 00:00:11, Serial0/0/0
C       10.30.100.0/29 is directly connected, Loopback100
C       10.30.101.0/25 is directly connected, Loopback101
     192.168.0.0/30 is subnetted, 1 subnets
R       192.168.0.0 [120/1] via 192.168.1.2, 00:00:11, Serial0/0/0
                    [120/1] via 192.168.2.2, 00:00:11, FastEthernet0/0
     192.168.1.0/30 is subnetted, 1 subnets
C       192.168.1.0 is directly connected, Serial0/0/0
     192.168.2.0/27 is subnetted, 1 subnets
C       192.168.2.0 is directly connected, FastEthernet0/0

Cisco Packet Tracer file:
Load and open the .pkt Lab file in Cisco Packet Tracer from here: RIPv2_Network_Summarization_Configuration.pkt