area

Function

The area command creates an OSPF area and displays the OSPF area view.

The undo area command deletes a specified area.

By default, no OSPF area is created.

Format

area { area-id | area-idipv4 }

undo area { area-id | area-idipv4 }

Parameters

Parameter	Description	Value
area-id	Specifies the area ID in decimal format.	The value is an integer from 0 to 4294967295. A decimal value is automatically converted to a dotted-decimal notation value based on the following rules: For a value of 255 or less, it is padded directly with three zeros in the format X.X.X.X. For example, a value of 255 will be converted to 0.0.0.255. For a value of 256 or greater, each X in the format X.X.X.X can be a maximum of 255. Starting from the right-most X, the X to its immediate left increments by 1 each time it reaches 256. For example, a value of 256 will be converted to 0.0.1.0, 511 will be converted to 0.0.1.255, and 65536 will be converted to 0.1.0.0.
area-idipv4	Specifies the area ID in dotted-decimal notation.	The value is in the format X.X.X.X, where each X represents a value from 0 to 255

Parameter

Description

Value

area-id

Specifies the area ID in decimal format.

The value is an integer from 0 to 4294967295.

A decimal value is automatically converted to a dotted-decimal notation value based on the following rules:

For a value of 255 or less, it is padded directly with three zeros in the format X.X.X.X. For example, a value of 255 will be converted to 0.0.0.255.
For a value of 256 or greater, each X in the format X.X.X.X can be a maximum of 255. Starting from the right-most X, the X to its immediate left increments by 1 each time it reaches 256. For example, a value of 256 will be converted to 0.0.1.0, 511 will be converted to 0.0.1.255, and 65536 will be converted to 0.1.0.0.

area-idipv4

Specifies the area ID in dotted-decimal notation.

The value is in the format X.X.X.X, where each X represents a value from 0 to 255

Views

OSPF view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
ospf	write

Usage Guidelines

Usage Scenario

The number of devices increases with the network expansion, which leads to a large LSDB on each OSPF-enabled device on a large-scale network. Consequently, route flapping frequently occurs, and a large number of OSPF packets are transmitted on the network, which wastes bandwidth resources.

OSPF addresses the preceding problem by logically partitioning an AS into different areas.

Prerequisites

Before creating and entering an OSPF area, you need to enter the OSPF process.

Precautions

After an AS is partitioned into different areas, not all areas are equal. The area with ID 0 is a backbone area. The backbone area is responsible for forwarding inter-area routes. In addition, the routing information between non-backbone areas must be forwarded through the backbone area.

The first time the area command is run, an OSPF area is created and the OSPF area view is displayed; running the area command later enters the OSPF area view only.

If the undo area command is run, all configurations in the OSPF area are deleted. Therefore, exercise caution when using the command.

Example

# Enter the view of an OSPF area.

<HUAWEI> system-view
[~HUAWEI] ospf 100
[*HUAWEI-ospf-100] area 0