Understand Open Shortest Path First (ospf) Design Guide

redistribute static
network 203.0.113.150 0.0.0.255 area 2
network 203.0.113.140 0.0.0.255 area 0
ip route 10.0.0.16 255.255.255.0 Ethernet0
ip route 198.51.100.1 255.255.0.0 Ethernet0
RTE#
interface Serial0
ip address 203.0.113.152 255.255.255.252
router ospf 10
network 203.0.113.150 0.0.0.255 area 2
The output of 
show ip route
on RTE:
RTE#show 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
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, * - candidate default
Gateway of last resort is not set
203.0.113.150 255.255.255.252 is subnetted, 1 subnets

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 C 203.0.113.150 is directly connected, Serial0
O IA 203.0.113.140 [110/74] via 203.0.113.151, 00:02:31, Serial0
O E2 198.51.100.1 [110/20] via 203.0.113.151, 00:02:32, Serial0
Note that the only external route that has appeared is 198.51.100.1, because we did not use the
subnet
keyword. Remember that if the 
subnet
keyword is not used, only routes that are not
subnetted are redistributed. In our case 10.0.0.16 is a class A route that is subnetted and it did not
get redistributed. Since the 
metric
keyword was not used (or a 
default-metric
statement under router
OSPF), the cost allocated to the external route is 20 (the default is 1 for BGP).
redistribute static metric 50 subnets
RTE#show 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
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, * - candidate default
Gateway of last resort is not set
10.0.0.16 255.255.255.0 is subnetted, 1 subnets
O E2 10.0.0.16 [110/50] via 203.0.113.151, 00:00:02, Serial0
203.0.113.150 255.255.255.252 is subnetted, 1 subnets
C 203.0.113.150 is directly connected, Serial0
O IA 203.0.113.140 [110/74] via 203.0.113.151, 00:00:02, Serial0
O E2 198.51.100.1 [110/50] via 203.0.113.151, 00:00:02, Serial0
Note that 10.0.0.16 has shown up now and the cost to external routes is 50. Since the external
routes are of type 2 (E2), the internal cost has not been added. Suppose now, we change the type
to E1: