nhrp entry multicast dynamic

Function

The nhrp entry multicast dynamic command enables the Hub to add dynamically registered Spokes to the NHRP multicast member table.

The undo nhrp entry multicast dynamic command disables the Hub to add dynamically registered Spokes from the NHRP multicast member table.

By default, no dynamically registered Spoke is added to the NHRP multicast member table.

Format

nhrp entry multicast dynamic

undo nhrp entry multicast dynamic

Parameters

None

Views

Tunnel interface view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
nhrp	write

Usage Guidelines

Usage Scenario

After the RIP or OSPF protocol is deployed on the DSVPN network, run the nhrp entry multicast dynamic command to enable the Hub to add dynamically registered Spokes to the multicast member table. This allows Spokes to learn routes from each other. After receiving routing multicast packets sent from Spokes, the Hub copies these routing multicast packets and forwards them to the destination Spoke based on the NHRP multicast member table. This allows routing multicast packets to be exchanged between Spokes.

Prerequisites

The following operations have been performed:

Run the interface tunnel command to create a tunnel interface and display the tunnel interface view.
Run the tunnel-protocol gre p2mp command to set the tunnel encapsulation mode to mGRE.

Configuration Impact

When a network has multiple Spokes and the Hub learns all the routes to these Spokes, the Hub consumes large CPU resources. In this case, you can configure a shortcut mode of DSVPN and the route summarization function to allow Spokes to directly communicate with each other.

Precautions

Run this command on the hub in both the shortcut and non-shortcut mode of DSVPN.

Example

# Configure the Spoke registered on Tunnel 0 to be dynamically added to the NHRP multicast member table of the Hub.

<HUAWEI> system-view
[~HUAWEI] nhrp enable
[*HUAWEI] interface tunnel 0
[*HUAWEI-Tunnel0] tunnel-protocol gre p2mp
[*HUAWEI-Tunnel0] nhrp enable
[*HUAWEI-Tunnel0] nhrp entry multicast dynamic