R3721-F3210-F3171-HP High-End Firewalls Network Management Configuration Guide-6PW101

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Configuring OSPFv3 area parameters
The stub area and virtual link features of OSPFv3 are the same as OSPFv2.
Splitting an OSPFv3 AS into multiple areas reduces the number of LSAs and extends OSPFv3
applications. For those non-backbone areas residing on the AS boundary, you can configure them as
stub areas to further reduce the size of routing tables and the number of LSAs.
Non-backbone areas exchange routing information via the backbone area. The backbone and
non-backbone areas—including the backbone itself—must be contiguous. In practice, necessary
physical links may not be available for this connectivity. You can configure virtual links to address the
problem.
Configuration prerequisites
Before you configure OSPFv3 area parameters, complete the following tasks:
• Enable IPv6 packet forwarding
• Configure OSPFv3 basic functions
Configuring an OSPFv3 stub area
Follow these guidelines when you configure an OSPFv3 stub area:
• You cannot remove an OSPFv3 area directly. Only when you remove all configurations in area view
and all interfaces attached to the area become down, can the area be removed.
• All the routers attached to a stub area must be configured with the stub command. The keyword
no-summary is only available on the ABR of the stub area.
• If you use the stub command with the keyword no-summary on an ABR, the ABR advertises a
default route in an Inter-Area-Prefix-LSA into the stub area. No AS-external-LSA, Inter-Area-Prefix-LSA
or Inter-Area-Router-LSA is advertised in the area. The stub area of this kind is also known as a
"totally stub area."
To configure an OSPFv3 stub area:
Ste
p
Command Remarks
1. Enter system view. system-view N/A
2. Enter OSPFv3 view.
ospfv3 [ process-id ] N/A
3. Enter OSPFv3 area view.
area area-id N/A
4. Configure the area as a stub
area.
stub [ no-summary ] Not configured by default.
5. Specify a cost for the default
route advertised to the stub
area.
default-cost value
Optional.
Defaults to 1.
Configuring an OSPFv3 virtual link
You can configure a virtual link to maintain connectivity between a non-backbone area and the
backbone, or in the backbone itself. Both ends of a virtual link are ABRs that must be configured with the
vlink-peer command. Do not configure virtual links in the areas of a GR-capable process.