​​Summary:
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1. Add a loopback interface to Belt with the IP address 184.51.1.2/24 and a default route to 184.51.1.1. This will simulate an Internet connection.
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2. Have Belt advertise the default route to the other routers via OSPF. The route should exist even if Belt does not have a default route.
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1. Add a loopback interface to Belt with the IP address 184.51.1.2/24 and a default route to 184.51.1.1. This will simulate an Internet connection.
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Belt: note after adding a default route to the internet, Belt becomes ASBR
int loopback 5
ip address 184.51.1.2 255.255.255.0
ip route 0.0.0.0 0.0.0.0 184.51.1.1
default-information originate
#Test:
before the change:
Shoe#show ip route
Codes: C - connected, S - static, 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
i - IS-IS, su - IS-IS summary, 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, 10 subnets, 2 masks
O IA 10.2.0.0/16 [110/138] via 10.51.1.1, 05:25:10, Serial1/0
C 10.1.3.0/24 is directly connected, FastEthernet0/0
O IA 10.0.0.0/24 [110/74] via 10.51.1.1, 18:41:46, Serial1/0
O IA 10.1.0.0/16 [110/138] via 10.51.1.1, 05:29:40, Serial1/0
C 10.51.1.0/24 is directly connected, Serial1/0
C 10.51.0.0/24 is directly connected, Loopback0
C 10.51.3.0/24 is directly connected, Loopback2
C 10.51.2.0/24 is directly connected, Loopback1
C 10.51.5.0/24 is directly connected, Loopback4
C 10.51.4.0/24 is directly connected, Loopback3
after the change:
Shoe#show ip route
Codes: C - connected, S - static, 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
i - IS-IS, su - IS-IS summary, 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 10.51.1.1 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 10 subnets, 2 masks
O IA 10.2.0.0/16 [110/138] via 10.51.1.1, 05:26:07, Serial1/0
C 10.1.3.0/24 is directly connected, FastEthernet0/0
O IA 10.0.0.0/24 [110/74] via 10.51.1.1, 18:42:43, Serial1/0
O IA 10.1.0.0/16 [110/138] via 10.51.1.1, 05:30:37, Serial1/0
C 10.51.1.0/24 is directly connected, Serial1/0
C 10.51.0.0/24 is directly connected, Loopback0
C 10.51.3.0/24 is directly connected, Loopback2
C 10.51.2.0/24 is directly connected, Loopback1
C 10.51.5.0/24 is directly connected, Loopback4
C 10.51.4.0/24 is directly connected, Loopback3
O*E2 0.0.0.0/0 [110/1] via 10.51.1.1, 00:00:10, Serial1/0 !----------------------------------------------------------- default route
Shoe#
2. Have Belt advertise the default route to the other routers via OSPF. The route should exist even if Belt does not have a default route.
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Belt:
int lo5 !-------------------shutdown the loopback interface, then use "always" command to advertise default route even there is no default route
shutdown
router ospf 1
no default-information originate
default-information originate always
-Yu
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