Configure SEFOS2

1. Configure the generation of a default external network.
   1. Type.

      SEFOS# configure terminal
      SEFOS(config)# router ospf
      

   2. Configure the OSPF router ID.

      SEFOS(config-router)# router-id 10.4.0.2
      

   3. Enable OSPF over the VLAN interface and associate the interface with an OSPF area.

      SEFOS(config-router)# network 10.4.0.2 area 0.0.0.0
      SEFOS(config-router)# network 10.2.2.2 area 0.0.0.2
      

   4. Configure area 0.0.0.2 as an NSSA area.

      SEFOS(config)# area 0.0.0.2 nssa
      

   5. Exit Router Configuration mode.

      SEFOS(config-router)# end
      SEFOS#
      

2. Examine the results.

   Type 5 External LSA must be generated for the default route.

   SEFOS# show ip ospf database external
    
   OSPF Router with ID (10.10.2.1)
                     AS External Link States
                     -----------------------
   LS age             : 0
   Options            : (No ToS Capability, DC)
   LS Type            : AS External Link
   Link State ID      : 0.0.0.0
   Advertising Router : 10.10.2.1
   LS Seq Number      : 0x80000001
   Checksum           : 0xb5dd
   Length             : 36
   Network Mask       : 0.0.0.0
   Metric Type        : 0x80
   Metric             : 40
   Forward Address    : 0.0.0.0
   Externel Route Tag : 0
   

3. Examine the configuration details in SEFOS2.

   The route entry for the default route must exist.

   SEFOS# show ip ospf route
    
   OSPF Process Routing Table
   Dest/Mask                     TOS NextHop/Interface Cost Rt.Type   Area
   ---------                     --- -------/--------- ---- -------   ----
   0.0.0.0/0.0.0.0            0   10.4.0.1/vlan1    40   Type2Ext  0.0.0.0
   10.2.2.0/255.255.255.0     0   0.0.0.0/vlan2     1    IntraArea 0.0.0.2
   10.4.0.0/255.255.0.0       0   0.0.0.0/vlan1     1    IntraArea 0.0.0.0
   10.10.0.0/255.255.0.0      0   10.4.0.1/vlan1    2    InterArea 0.0.0.0