Configuring an ospf nssa area, Network requirements, Configuration procedure – H3C Technologies H3C S12500 Series Switches User Manual

Page 127

Advertising
background image

111

[SwitchC] display ospf routing

OSPF Process 1 with Router ID 10.4.1.1

Routing Tables

Routing for Network

Destination Cost Type NextHop AdvRouter Area

0.0.0.0/0 4 Inter 10.2.1.1 10.2.1.1 0.0.0.1

10.2.1.0/24 3 Transit 10.2.1.2 10.4.1.1 0.0.0.1

10.4.1.0/24 3 Stub 10.4.1.1 10.4.1.1 0.0.0.1

Total Nets: 3

Intra Area: 2 Inter Area: 1 ASE: 0 NSSA: 0

The output shows that routing entries on the stub router are further reduced, containing only one

default external route.

Configuring an OSPF NSSA area

Network requirements

Figure 44

shows an AS split into three areas, where all switches run OSPF. Switch A and Switch B act as

ABRs to forward routing information between areas.
Configure Area 1 as an NSSA area and configure Switch C as the ASBR to redistribute static routes into
the AS.

Figure 44 Network diagram

Configuration procedure

1.

Configure IP addresses for interfaces.

2.

Configure basic OSPF (see "

Configuring basic OSPF

").

3.

Configure Area 1 as an NSSA area:
# Configure Switch A.

<SwitchA> system-view

[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-0.0.0.1] quit

Area 0

Area 1
NSSA

Area 2

Switch C

Vlan-int100

10.1.1.2/24

Vlan-int100
10.1.1.1/24

Vlan-int300
10.4.1.1/24

Vlan-int200
10.2.1.2/24

Switch B

Vlan-int200
10.3.1.1/24

Vlan-int200
10.3.1.2/24

Switch A

Vlan-int200
10.2.1.1/24

Vlan-int300

10.5.1.1/24

Switch D

ASBR

Advertising