All,

Need some clarification, I made one of Marko's ospf articles into a bigger ospf 
domain, and this question came up--not sure if there is an answer already ...

Question: who selects ip address to use as Forward (FW) address the ASBR ? can 
this be influence manually...

here is the link to the article : 
http://blog.ipexpert.com/2010/09/27/quick-look-into-ospf-database-nssa-external-lsa/

before i added a router(r6)  to R1 ( using Serial interface) this how the  
external db looks like on R4:

R4#sh ip os database nssa-external 

            OSPF Router with ID (4.4.4.4) (Process ID 1)

                Type-7 AS External Link States (Area 145)

  LS age: 905
  Options: (No TOS-capability, Type 7/5 translation, DC)
  LS Type: AS External Link
  Link State ID: 11.11.11.11 (External Network Number )
  Advertising Router: 1.1.1.1
  LS Seq Number: 80000002
  Checksum: 0xBDF1
  Length: 36
  Network Mask: /32
        Metric Type: 2 (Larger than any link state path)
        TOS: 0 
        Metric: 20 
        Forward Address: 145.145.145.1
        External Route Tag: 0



After adding R6 to R1.... here is the DB on R4:

R4#sh ip os database nssa-external 

            OSPF Router with ID (4.4.4.4) (Process ID 1)

                Type-7 AS External Link States (Area 145)

  LS age: 3
  Options: (No TOS-capability, Type 7/5 translation, DC)
  LS Type: AS External Link
  Link State ID: 11.11.11.11 (External Network Number )
  Advertising Router: 1.1.1.1
  LS Seq Number: 80000003
  Checksum: 0x85AD
  Length: 36
  Network Mask: /32
        Metric Type: 2 (Larger than any link state path)
        TOS: 0 
        Metric: 20 
        Forward Address: 16.16.16.1
        External Route Tag: 0


the FW add changed on R4 when i brought a link ( serial on R1 connecting to R6)

configs:

R4#sh run | s router
router ospf 1
 router-id 4.4.4.4
 log-adjacency-changes
 area 145 nssa
 network 4.4.4.4 0.0.0.0 area 0
 network 24.24.24.4 0.0.0.0 area 0
 network 45.45.45.4 0.0.0.0 area 0
 network 145.145.145.4 0.0.0.0 area 145


 R1#sh run | s router 
router ospf 1
 router-id 1.1.1.1
 log-adjacency-changes
 area 145 nssa
 redistribute connected subnets route-map CON-to-OSPF
 network 16.16.16.1 0.0.0.0 area 145
 network 145.145.145.1 0.0.0.0 area 145



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