3Com S7906E Configuration Manual page 693

Figure 1-25 Network diagram for OSPF NSSA area configuration
Configuration procedure
1) Configure IP addresses for interfaces.
2) Configure OSPF basic functions (refer to
3) Configure Area 1 as an NSSA area.
# Configure Switch A.
[SwitchA] ospf
[SwitchA-ospf-1] area 1
[SwitchA-ospf-1-area-0.0.0.1] nssa default-route-advertise no-summary
[SwitchA-ospf-1-area-0.0.0.0] quit
[SwitchA-ospf-1] quit
# Configure Switch C.
[SwitchC] ospf
[SwitchC-ospf-1] area 1
[SwitchC-ospf-1-area-0.0.0.1] nssa
[SwitchC-ospf-1-area-0.0.0.1] quit
[SwitchC-ospf-1] quit
It is recommended to configure the nssa command with the keyword default-route-advertise
no-summary on Switch A (an ABR) to reduce the routing table size on NSSA routers. On other NSSA
routers, use the nssa command.
# Display OSPF routing information on Switch C.
[SwitchC] display ospf routing
OSPF Process 1 with Router ID 10.4.1.1
Routing for Network
Routing Tables
Configuring OSPF Basic Functions
1-60
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