R1 Configuration:
Interface Loopback1
Ip address 1.1.1.1 255.255.255.0
!
Interface Loopback2
Ip address 1.1.2.1 255.255.255.0
!
Interface Loopback3
Ip address 1.1.3.1 255.255.255.0
!
Interface Serial1/1
Ip address 10.0.1.1 255.255.255.0
Serial restart-delay 0
!
Router ospf 1
Log-adjacency-changes
Network 1.1.1.0 0.0.255 area 1
Network 1.1.2.0 0.0.255 area 1
Network 1.1.3.0 0.0.255 area 1
Network 10.0.1.0 0.0.0.255 area 1
!
R2 Configuration:
Interface Serial1/0
Ip address 10.0.1.2 255.255.255.0
Serial restart-delay 0
!
Interface Serial1/1
Ip address 10.0.2.1 255.255.255.0
Serial restart-delay 0
!
Router ospf 1
Log-adjacency-changes
Network 10.0.1.0 0.0.0.255 area 1
Network 10.0.2.0 0.0.0.255 area 0
!
R3 Configuration:
Interface Serial1/0
Ip address 10.0.2.2 255.255.255.0
Serial restart-delay 0
!
Interface Serial1/1
Ip address 10.0.3.1 255.255.255.0
Serial restart-delay 0
!
Router ospf 1
Log-adjacency-changes
Network 10.0.2.0 0.0.0.255 area 0
Network 10.0.3.0 0.0.0.255 area 2
!
R4 Configuration:
Interface Loopback1
Ip address 4.4.1.4 255.255.255.0
!
Interface Loopback2
Ip address 4.4.2.4 255.255.255.0
!
Interface Loopback3
Ip address 4.4.3.4 255.255.255.0
!
Interface Serial1/0
Ip address 10.0.3.2 255.255.255.0
Serial restart-delay 0
!
Router ospf 1
Log-adjacency-changes
Network 4.4.1.0 0.0.0.255 area 2
Network 4.4.2.0 0.0.0.255 area 2
Network 4.4.3.0 0.0.0.255 area 2
Network 10.0.3.0 0.0.0.255 area 2
!
At the end of the preceding command, configure the OSPF route tables for each vro as follows:
R1 # show ip route
Codes: C-connected, S-static, R-RIP, M-mobile, B-BGP
D-OSPF, EX-VPN 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
I-IS, su-IS summary, L1-IS-level-1, L2-IS level-2
Ia-IS inter area, *-candidate default, U-per-user static route
O-ODR, P-periodic downloaded static route
Gateway of last resort is not set
1.0.0.0/24 is subnetted, 3 subnets
C 1.1.1.0 is directly connected, Loopback1
C 1.1.2.0 is directly connected, Loopback2
C 1.1.3.0 is directly connected, Loopback3
4.0.0.0/32 is subnetted, 3 subnets
O ia 4.4.1.4 [110/193] via 10.0.1.2, 00:07:19, Serial1/1
O ia 4.4.2.4 [110/193] via 10.0.1.2, 00:07:19, Serial1/1
O ia 4.4.3.4 [110/193] via 10.0.1.2, 00:07:19, Serial1/1
10.0.0.0/24 is subnetted, 3 subnets
O ia 10.0.2.0 [110/128] via 10.0.1.2, 00:44:09, Serial1/1
O ia 10.0.3.0 [110/192] via 10.0.1.2, 00:07:19, Serial1/1
C 10.0.1.0 is directly connected, Serial1/
R2 # show ip route
Codes: C-connected, S-static, R-RIP, M-mobile, B-BGP
D-OSPF, EX-VPN 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
I-IS, su-IS summary, L1-IS-level-1, L2-IS level-2
Ia-IS inter area, *-candidate default, U-per-user static route
O-ODR, P-periodic downloaded static route
Gateway of last resort is not set
1.0.0.0/32 is subnetted, 3 subnets
O 1.1.1.1 [110/65] via 10.0.1.1, 00:44:42, Serial1/0
O 1.1.3.1 [110/65] via 10.0.1.1, 00:44:42, Serial1/0
O 1.1.2.1 [110/65] via 10.0.1.1, 00:44:42, Serial1/0
4.0.0.0/32 is subnetted, 3 subnets
O ia 4.4.1.4 [110/129] via 10.0.2.2, 00:07:52, Serial1/1
O ia 4.4.2.4 [110/129] via 10.0.2.2, 00:07:52, Serial1/1
O ia 4.4.3.4 [110/129] via 10.0.2.2, 00:07:52, Serial1/1
10.0.0.0/24 is subnetted, 3 subnets
C 10.0.2.0 is directly connected, Serial1/1
O ia 10.0.3.0 [110/128] via 10.0.2.2, 00:07:52, Serial1/1
C 10.0.1.0 is directly connected, Serial1/0
R3 # show ip route
Codes: C-connected, S-static, R-RIP, M-mobile, B-BGP
D-OSPF, EX-VPN 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
I-IS, su-IS summary, L1-IS-level-1, L2-IS level-2
Ia-IS inter area, *-candidate default, U-per-user static route
O-ODR, P-periodic downloaded static route
Gateway of last resort is not set
1.0.0.0/32 is subnetted, 3 subnets
O ia 1.1.1.1 [110/129] via 10.0.2.1, 00:08:09, Serial1/0
O ia 1.1.3.1 [110/129] via 10.0.2.1, 00:08:09, Serial1/0
O ia 1.1.2.1 [110/129] via 10.0.2.1, 00:08:09, Serial1/0
4.0.0.0/32 is subnetted, 3 subnets
O 4.4.1.4 [110/65] via 10.0.3.2, 00:08:19, Serial1/1
O 4.4.2.4 [110/65] via 10.0.3.2, 00:08:19, Serial1/1
O 4.4.3.4 [110/65] via 10.0.3.2, 00:08:19, Serial1/1
10.0.0.0/24 is subnetted, 3 subnets
C 10.0.2.0 is directly connected, Serial1/0
C 10.0.3.0 is directly connected, Serial1/1
O ia 10.0.1.0 [110/128] via 10.0.2.1, 00:08:09, Serial1/0
R4 # show ip route
* Oct 10 17:49:31. 863: % SYS-5-CONFIG_ I: Configured from console by consoleroute
Codes: C-connected, S-static, R-RIP, M-mobile, B-BGP
D-OSPF, EX-VPN 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
I-IS, su-IS summary, L1-IS-level-1, L2-IS level-2
Ia-IS inter area, *-candidate default, U-per-user static route
O-ODR, P-periodic downloaded static route
Gateway of last resort is not set
1.0.0.0/32 is subnetted, 3 subnets
O ia 1.1.1.1 [110/193] via 10.0.3.1, 00:09:25, Serial1/0
O ia 1.1.3.1 [110/193] via 10.0.3.1, 00:09:25, Serial1/0
O ia 1.1.2.1 [110/193] via 10.0.3.1, 00:09:25, Serial1/0
4.0.0.0/24 is subnetted, 3 subnets
C 4.4.1.0 is directly connected, Loopback1
C 4.4.2.0 is directly connected, Loopback2
C 4.4.3.0 is directly connected, Loopback3
10.0.0.0/24 is subnetted, 3 subnets
O ia 10.0.2.0 [110/128] via 10.0.3.1, 00:09:35, Serial1/0
C 10.0.3.0 is directly connected, Serial1/0
O ia 10.0.1.0 [110/192] via 10.0.3.1, 00:09:25, Serial1/0
On R2 (ABR) and R3 (ABR), the networks in area 1 and Area 2 are summarized, and area 1 1.1.1.0-1.1.3.0 is summarized into 1.1.0.0/22, configure area 2 4.4.1.0-4.4.3.0 to 4.4.0.0/22 as follows:
R2 (config) # router ospf 1
R2 (config-router) # area 1 range 1.1.0.0 255.255.252.0
R3 (config) # router ospf 1
R3 (config-router) # area 2 range 4.4.0.0 255.255.252.0
Route table after configuration is summarized:
R1 # show ip route
Codes: C-connected, S-static, R-RIP, M-mobile, B-BGP
D-OSPF, EX-VPN 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
I-IS, su-IS summary, L1-IS-level-1, L2-IS level-2
Ia-IS inter area, *-candidate default, U-per-user static route
O-ODR, P-periodic downloaded static route
Gateway of last resort is not set
1.0.0.0/24 is subnetted, 3 subnets
C 1.1.1.0 is directly connected, Loopback1
C 1.1.2.0 is directly connected, Loopback2
C 1.1.3.0 is directly connected, Loopback3
4.0.0.0/22 is subnetted, 1 subnets
O ia 4.4.0.0 [110/193] via 10.0.1.2, 00:04:23, Serial1/1 // summarized route
10.0.0.0/24 is subnetted, 3 subnets
O ia 10.0.2.0 [110/128] via 10.0.1.2, 01:04:01, Serial1/1
O ia 10.0.3.0 [110/192] via 10.0.1.2, 00:27:11, Serial1/1
C 10.0.1.0 is directly connected, Serial
R2 (config-router) # do show ip route
Codes: C-connected, S-static, R-RIP, M-mobile, B-BGP
D-OSPF, EX-VPN 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
I-IS, su-IS summary, L1-IS-level-1, L2-IS level-2
Ia-IS inter area, *-candidate default, U-per-user static route
O-ODR, P-periodic downloaded static route
Gateway of last resort is not set
1.0.0.0/8 is variably subnetted, 4 subnets, 2 masks
O 1.1.1.1/32 [110/65] via 10.0.1.1, 00:05:28, Serial1/0
O 1.1.0.0/22 is a summary, 00:05:28, Null0
O 1.1.3.1/32 [110/65] via 10.0.1.1, 00:05:28, Serial1/0
O 1.1.2.1/32 [110/65] via 10.0.1.1, 00:05:28, Serial1/0
4.0.0.0/22 is subnetted, 1 subnets
O ia 4.4.0.0 [110/129] via 10.0.2.2, 00:04:54, Serial1/1 // summarized route
10.0.0.0/24 is subnetted, 3 subnets
C 10.0.2.0 is directly connected, Serial1/1
O ia 10.0.3.0 [110/128] via 10.0.2.2, 00:05:28, Serial1/1
C 10.0.1.0 is directly connected, Serial1/0
R3 (config-router) # do show ip route
Codes: C-connected, S-static, R-RIP, M-mobile, B-BGP
D-OSPF, EX-VPN 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
I-IS, su-IS summary, L1-IS-level-1, L2-IS level-2
Ia-IS inter area, *-candidate default, U-per-user static route
O-ODR, P-periodic downloaded static route
Gateway of last resort is not set
1.0.0.0/22 is subnetted, 1 subnets
O ia 1.1.0.0 [110/129] via 10.0.2.1, 00:05:27, Serial1/0 // summarized route
4.0.0.0/8 is variably subnetted, 4 subnets, 2 masks
O 4.4.0.0/22 is a summary, 00:05:27, Null0
O 4.4.1.4/32 [110/65] via 10.0.3.2, 00:05:27, Serial1/1
O 4.4.2.4/32 [110/65] via 10.0.3.2, 00:05:27, Serial1/1
O 4.4.3.4/32 [110/65] via 10.0.3.2, 00:05:27, Serial1/1
10.0.0.0/24 is subnetted, 3 subnets
C 10.0.2.0 is directly connected, Serial1/0
C 10.0.3.0 is directly connected, Serial1/1
O ia 10.0.1.0 [110/128] via 10.0.2.1, 00:05:27, Serial1/0
R4 # show ip route
Codes: C-connected, S-static, R-RIP, M-mobile, B-BGP
D-OSPF, EX-VPN 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
I-IS, su-IS summary, L1-IS-level-1, L2-IS level-2
Ia-IS inter area, *-candidate default, U-per-user static route
O-ODR, P-periodic downloaded static route
Gateway of last resort is not set
1.0.0.0/22 is subnetted, 1 subnets
O ia 1.1.0.0 [110/193] via 10.0.3.1, 00:06:27, Serial1/0 // summarized route
4.0.0.0/24 is subnetted, 3 subnets
C 4.4.1.0 is directly connected, Loopback1
C 4.4.2.0 is directly connected, Loopback2
C 4.4.3.0 is directly connected, Loopback3
10.0.0.0/24 is subnetted, 3 subnets
O ia 10.0.2.0 [110/128] via 10.0.3.1, 00:28:42, Serial1/0
C 10.0.3.0 is directly connected, Serial1/0
O ia 10.0.1.0 [110/192] via 10.0.3.1, 00:28:32, Serial1/0