3Com 5500G Configuration procedure is omitted, Nssa area configuration 1 area 1 is an Nssa area

Configuring a (Totally) NSSA Area 113

<SwitchC> system-view

[SwitchC] ip route-static 2.0.0.0 8 10.4.1.2

# Configure OSPF for area 1.

[SwitchC] ospf 1 router-id 3.3.3.3 [SwitchC-ospf-1] area 1 [SwitchC-ospf-1-area-0.0.0.1] network 10.2.1.0 0.0.0.255

[SwitchC-ospf-1-area-0.0.0.1] network 10.4.1.0 0.0.0.255

[SwitchC-ospf-1-area-0.0.0.1] quit

# Redistribute the static route to specify Switch C as an ASBR.

[SwitchC-ospf-1] import-route static

[SwitchC-ospf-1] quit

	■	Configure Switch D.
	# Create VLANs and configure IP addresses of the VLAN interfaces. The
	configuration procedure is omitted.
	# Configure a static route of 1.0.0.0/8.
	<SwitchD> system-view
	[SwitchD] ip route-static 1.0.0.0 8 10.5.1.2
	# Configure OSPF for area 2.
	[SwitchD] ospf 1 router-id 4.4.4.4
	[SwitchD-ospf-1] area 2
	[SwitchD-ospf-1-area-0.0.0.2] network 10.3.1.0 0.0.0.255
	[SwitchD-ospf-1-area-0.0.0.2] network 10.5.1.0 0.0.0.255
	[SwitchD-ospf-1-area-0.0.0.2] quit
	# Redistribute the static route to specify Switch D as an ASBR.
	[SwitchD-ospf-1] import-route static
	[SwitchD-ospf-1] quit
n	■ The above-mentioned steps configure non-backbone areas, backbone area,
		and ABRs/ASBRs.
	■ By using the display ospf lsdb command on Switch C, you can see that Type-3
		LSAs, Type-4 LSAs, and Type-5 LSAs exist in the link state database (LSDB). You
		can control the generation of Type-4 LSAs, Type-5 LSAs, and Type-7 LSAs by
		configuring the NSSA attribute.

NSSA area configuration 1 (area 1 is an NSSA area)

n After this configuration, packets destined for an IP address (in another AS) advertised by the ASBR of the NSSA area will be forwarded by the ASBR, while packets destined for an IP address (in another AS) not advertised by the ASBR will be dropped.

Based on the configuration in “Non-backbone area and backbone area configuration (area 1 is a non-backbone area)” on page 107, perform the following steps: