A quiz :D

Site-A is a CE that peers with PE using OSPF area 0. See the exhibit below:

site-a#sh ip route | beg Gate
Gateway of last resort is not set

100.0.0.0/32 is subnetted, 2 subnets
O IA 100.1.1.1 [110/101] via 12.0.0.1, 00:00:53, Serial0/0
O IA 100.1.2.1 [110/101] via 12.0.0.1, 00:00:38, Serial0/0
200.1.1.0/30 is subnetted, 1 subnets
O IA 200.1.1.0 [110/51] via 12.0.0.1, 00:02:08, Serial0/0
12.0.0.0/30 is subnetted, 1 subnets
C 12.0.0.0 is directly connected, Serial0/0
13.0.0.0/24 is subnetted, 1 subnets
C 13.0.0.0 is directly connected, Loopback1
14.0.0.0/24 is subnetted, 1 subnets
C 14.0.0.0 is directly connected, Loopback2
site-a#

100.1.1.1, 100.1.2.1 and 200.1.1.0/30 are from site-B, site-B CE also peers to PE using OSPF area 0. What causes the OSPF route as shown in the exhibit to be inter-area route? Since both site-A and site-B are using OSPF in the same area over MPLS?

Look at the second exhibit:

site-a#sh ip route | begin Gate
Gateway of last resort is not set

100.0.0.0/32 is subnetted, 2 subnets
O 100.1.1.1 [110/102] via 12.0.0.1, 00:01:04, Serial0/0
O 100.1.2.1 [110/102] via 12.0.0.1, 00:01:04, Serial0/0
200.1.1.0/30 is subnetted, 1 subnets
O 200.1.1.0 [110/101] via 12.0.0.1, 00:01:04, Serial0/0
22.0.0.0/32 is subnetted, 1 subnets
O E2 22.22.22.22 [110/1] via 12.0.0.1, 00:01:35, Serial0/0
11.0.0.0/32 is subnetted, 1 subnets
O E2 11.11.11.11 [110/1] via 12.0.0.1, 00:03:31, Serial0/0
12.0.0.0/30 is subnetted, 1 subnets
C 12.0.0.0 is directly connected, Serial0/0
13.0.0.0/24 is subnetted, 1 subnets
C 13.0.0.0 is directly connected, Loopback1
14.0.0.0/24 is subnetted, 1 subnets
C 14.0.0.0 is directly connected, Loopback2
site-a#

100.1.1.1, 100.1.2.1 and 200.1.1.0/30 are from site-B, site-B peers with PE using OSPF area 0. What have I configured to cause the OSPF route to be intra-area scope? 🙂

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