route selection when forwarding address is non zero

i have a senario in which forwarding address is non zero

router picks route via this non zero forwarding address , even though it
has same e
equal cost route.

when i change FA to zero ( 0.0.0.0) by changing network type , then
routing table adds other equal cost route.

R1#show ip route ospf
     151.90.0.0/24 is subnetted, 4 subnets
O E2 151.90.103.0 [110/20] via 151.90.163.3, 00:00:01, Ethernet0/0
R1#

R1#show ip ospf database external

            OSPF Router with ID (151.90.163.1) (Process ID 1)

                Type-5 AS External Link States

  Routing Bit Set on this LSA
  LS age: 10
  Options: (No TOS-capability, DC)
  LS Type: AS External Link
  Link State ID: 151.90.103.0 (External Network Number )
  Advertising Router: 151.90.163.6
  LS Seq Number: 80000003
  Checksum: 0xF719
  Length: 36
  Network Mask: /24
        Metric Type: 2 (Larger than any link state path)
        TOS: 0
        Metric: 20
        Forward Address: 151.90.163.3
        External Route Tag: 0

R1(config)#int Ethernet0/0
R1(config-if)#ip ospf network point-to-point

R1#show ip ospf database external

            OSPF Router with ID (151.90.163.1) (Process ID 1)

                Type-5 AS External Link States

  Routing Bit Set on this LSA
  LS age: 553
  Options: (No TOS-capability, DC)
  LS Type: AS External Link
  Link State ID: 151.90.103.0 (External Network Number )
  Advertising Router: 151.90.163.6
  LS Seq Number: 80000004
  Checksum: 0xBCEB
  Length: 36
  Network Mask: /24
        Metric Type: 2 (Larger than any link state path)
        TOS: 0
        Metric: 20
        Forward Address: 0.0.0.0
        External Route Tag: 0

R1#show ip ospf border
R1#show ip ospf border-routers

OSPF Process 1 internal Routing Table

Codes: i - Intra-area route, I - Inter-area route

i 151.90.163.6 [10] via 151.90.163.6, Ethernet0/0, ASBR, Area 0, SPF 18
i 151.90.163.6 [10] via 151.90.16.6, Ethernet0/1, ASBR, Area 0, SPF 18
R1#

O E2 151.90.103.0/24 [110/20] via 151.90.163.6, 00:00:15, Ethernet0/0
                        [110/20] via 151.90.16.6, 00:00:15, Ethernet0/1

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Received on Sat Sep 14 2013 - 15:33:35 ART