Example 2: Virtual Links; Configuring Ospf For A Virtual Link On Switch A - HP 438031-B21 - 1:10Gb Ethernet BL-c Switch Application Manual

Example 2: Virtual links

In the example shown in the following figure, area 2 is not physically connected to the backbone as is
usually required. Instead, area 2 will be connected to the backbone via a virtual link through area 1. The
virtual link must be configured at each endpoint.
Configuring a virtual link
Figure 22

Configuring OSPF for a virtual link on Switch A

1.
Configure IP interfaces on each network that will be attached to the switch.
In this example, two IP interfaces are needed on Switch A: one for the backbone network on
10.10.7.0/24 and one for the transit area network on 10.10.12.0/24.
>> # /cfg/l3/if 1
>> IP Interface 1 # addr 10.10.7.1
>> IP Interface 1 # mask 255.255.255.0 (Set IP mask on backbone network)
>> IP Interface 1 # enable
>> IP Interface 1 # ../if 2
>> IP Interface 2 # addr 10.10.12.1 (Set IP address on
>> IP Interface 2 # mask 255.255.255.0 (Set IP mask on
>> IP Interface 2 # enable
2.
Configure the router ID.
3. A router ID is required when configuring virtual links. Later, when configuring the other end of the
virtual link on Switch B, the router ID specified here will be used as the target virtual neighbor (nbr)
address
>> IP Interface 2 # /cfg/l3/rtrid 10.10.10.1
4.
Enable OSPF.
>> IP # /cfg/l3/ospf/on
5.
Define the backbone.
>> Open Shortest Path First # aindex 0
>> OSPF Area (index) 0 # areaid 0.0.0.0
>> OSPF Area (index) 0 # type transit
>> OSPF Area (index) 0 # enable
6.
Define the transit area.
7.
The area that contains the virtual link must be configured as a 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
(Select menu for IP interface 1)
(Set IP address on backbone network)
(Enable IP interface 1)
(Select menu for IP interface 2)
transit area network)
transit area network)
(Enable interface 2)
(Set static router ID)
(Select menu for area index 0)
(Set the area ID)
(Define backbone as transit type)
(Enable the area)
(Select menu for area index 1)
(Define area as transit type)
(Enable the area)
OSPF
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