Other Virtual Link Options; Example 3: Summarizing Routes - HP 438031-B21 - 1:10Gb Ethernet BL-c Switch Application Manual

8. Define the transit area.
>> OSPF Area (index) 0 # ../aindex 1
>> OSPF Area (index) 1 # areaid 0.0.0.1(Set the area ID for OSPF area 1)
>> OSPF Area (index) 1 # type transit
>> OSPF Area (index) 1 # enable
9. Define the stub area.
>> OSPF Area (index) 1 # ../aindex 2
>> OSPF Area (index) 2 # areaid 0.0.0.2(Set the area ID for OSPF area 2)
>> OSPF Area (index) 2 # type stub
>> OSPF Area (index) 2 # enable
10. Attach the network interface to the backbone.
>> OSPF Area (index) 2 # ../if 1
>> OSPF Interface 1 # aindex 1
>> OSPF Interface 1 # enable
11. Attach the network interface to the transit area.
>> OSPF Interface 1 # ../if 2
>> OSPF Interface 2 # aindex 2
>> OSPF Interface 2 # enable
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
>> OSPF Virtual Link 1 # aindex 1
>> OSPF Virtual Link 1 # nbr 10.10.10.1(Specify the router ID
>> OSPF Virtual Link 1 # enable
14. Apply and save the configuration changes.
>> OSPF Interface 2 # apply
>> OSPF Interface 2 # save

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.
(Select menu for area index 1)
(Define area as transit type)
(Enable the area)
(Select the menu for area index 2)
(Define area as stub type)
(Enable the area)
(Select OSPF menu for IP interface 1)
(Attach network to transit area index)
(Enable the transit area interface)
(Select OSPF menu for IP interface 2)
(Attach network to stub area index)
(Enable the stub area interface)
(Specify a virtual link number)
(Specify the transit area
for the virtual link)
of the recipient)
(Enable the virtual link)
(Apply all changes)
(Save all changes)
OSPF
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