Configuring An Ospf Nssa Area - 3Com MSR 50 Series Configuration Manual

960 C 58: OSPF C
HAPTER
n
Configuring an OSPF
NSSA Area
ONFIGURATION
# Display OSPF routing table information on RouterC
[RouterC] display ospf routing
OSPF Process 1 with Router ID 10.4.1.1
Routing for Network
Destination
0.0.0.0/0
10.2.1.0/24
10.4.1.0/24
Total Nets: 3
Intra Area: 2
After this configuration, routing table entries on the stub router are further
reduced, containing only one default external route.
Network requirements
Figure 291 shows an AS is split into three areas, where all routers run OSPF.
RouterA and RouterB act as ABRs to forward routing information between areas.
It is required to configure Area1 as an NSSA area, RouterC as an ASBR to
redistribute static routes into the AS.
Network diagram
Figure 291 OSPF NSSA area configuration network diagram
Router A
Eth1/0
10.1.1.1 /24
Eth1/1
10.2.1 .1/24
Area 1
Eth1 /0
NSSA
10 .2 .1.2/24
ASBR
Eth1/1
Router C
10 .4.1.1/24
Configuration procedure
1 Configure IP addresses for interfaces (omitted).
2 Configuring OSPF basic functions (refer to
page 939).
3 Configure Area1 as NSSA area.
# Configure RouterA
[RouterA] ospf
[RouterA-ospf-1] area 1
[RouterA-ospf-1-area-0.0.0.1] nssa default-route-advertise no-summary
[RouterA-ospf-1-area-0.0.0.1] quit
Routing Tables
Cost Type NextHop
65536 Inter 10.2.1.1
65535 Transit 10.2.1.2
3 Stub 10.4.1.1
Inter Area: 1 ASE: 0
Area 0
Router B
Eth1/0
10 .1 .1.2/24
Area 2
Eth1/0
10 .5.1.1/24
AdvRouter
10.2.1.1
10.4.1.1
10.4.1.1
NSSA: 0
Eth1/1
10.3.1.1 /24
Eth1/0
10.3.1.2/24
ASBR
Router D
"Configuring OSPF Basic Functions" on
Area
0.0.0.1
0.0.0.1
0.0.0.1