HP 445946-001 Other Virtual Link Options, The, OSPF, Switch A in step, 9.Define the stub area, 8.Define the transit area, 12.Configure the virtual link

OSPF

8.Define the transit area.

>> OSPF Area (index) 0 # ../aindex 1 (Select menu for area index 1)

>>OSPF Area (index) 1 # areaid 0.0.0.1(Set the area ID for OSPF area 1)

>>OSPF Area (index) 1 # type transit (Define area as transit type)

>> OSPF Area (index) 1 # enable (Enable the area)

9.Define the stub area.

>>OSPF Area (index) 1 # ../aindex 2 (Select the menu for area index 2)

>>OSPF Area (index) 2 # areaid 0.0.0.2(Set the area ID for OSPF area 2)

>>	OSPF	Area	(index)	2	#	type stub	(Define	area as stub type)
>>	OSPF	Area	(index)	2	#	enable	(Enable	the area)

10.Attach the network interface to the backbone.

>>OSPF Area (index) 2 # ../if 1

>>OSPF Interface 1 # aindex 1

>>OSPF Interface 1 # enable

(Select OSPF menu for IP interface 1) (Attach network to transit area index) (Enable the transit area interface)

11.Attach the network interface to the transit area.

>>OSPF Interface 1 # ../if 2

>>OSPF Interface 2 # aindex 2

>>OSPF Interface 2 # enable

(Select OSPF menu for IP interface 2) (Attach network to stub area index) (Enable the stub area interface)

12.Configure the virtual link.

13.The nbr router ID configured in this step must be the same as the router ID that was configured for

Switch A in step 2.

>> OSPF Interface 2 # ../virt 1		(Specify	a virtual link number)
>> OSPF Virtual Link 1 # aindex	1	(Specify	the transit area
		for the	virtual link)

>>OSPF Virtual Link 1 # nbr 10.10.10.1(Specify the router ID of the recipient)

>> OSPF Virtual Link 1 # enable (Enable the virtual link)

14.Apply and save the configuration changes.

>>	OSPF	Interface	2	#	apply	(Apply all changes)
>>	OSPF	Interface	2	#	save	(Save all changes)

Other Virtual Link Options

•You can use redundant paths by configuring multiple virtual links.

•Only the endpoints of the virtual link are configured. The virtual link path may traverse multiple routers in an area as long as there is a routable path between the endpoints.

Example 3: Summarizing routes

By default, ABRs advertise all the network addresses from one area into another area. Route summarization can be used for consolidating advertised addresses and reducing the perceived complexity of the network.

If the network IP addresses in an area are assigned to a contiguous subnet range, you can configure the ABR to advertise a single summary route that includes all the individual IP addresses within the area.

The following example shows one summary route from area 1 (stub area) injected into area 0 (the backbone). The summary route consists of all IP addresses from 36.128.192.0 through 36.128.254.255 except for the routes in the range 36.128.200.0 through 36.128.200.255.

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