ip topology

Function

The ip topology command creates a topology instance.

The undo ip topology command deletes a topology instance.

By default, no topology instance is created.

Format

ip topology topology-name

undo ip topology topology-name

Parameters

Parameter	Description	Value
topology-name	Specifies the name of a topology instance.	The value is a string of 1 to 31 case-insensitive characters. base is reserved and cannot be configured.

Parameter

Description

Value

topology-name

Specifies the name of a topology instance.

The value is a string of 1 to 31 case-insensitive characters. base is reserved and cannot be configured.

Views

System view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
route-base	write

Usage Guidelines

Usage Scenario

Multi-topology is usually applied to multicast. The RPF check depends on the unicast routing table. If multicast uses the default unicast routing table, two problems occur:

Unicast route changes affect the establishment of a multicast distribution tree because multicast highly depends on unicast.
Multicast cannot plan a multicast distribution tree, independent of unicast.
Therefore, besides the default unicast topology, a multicast topology needs to be planned for multicast.

Configuration Impact

Protocols can use a topology only after logical topologies are planned on the basis of a physical topology.

Precautions

The topology named base is a base topology, and can neither be configured nor deleted.

Running the undo ip topology command deletes all service configurations of the specified topology instance along with the topology instance. Therefore, exercise caution when running this command.

Example

# Create a topology instance named topo1.

<HUAWEI> system-view
[~HUAWEI] ip topology topo1