hello-option dr-priority (IPv4)

Function

The hello-option dr-priority command configures a designated router (DR) election priority for a Router.

The undo hello-option dr-priority command restores the default priority.

By default, the DR election priority of a Router is 1.

Format

hello-option dr-priority priority

undo hello-option dr-priority

Parameters

Parameter	Description	Value
priority	Specifies a DR election priority. A larger value indicates a higher priority.	The value is an integer ranging from 0 to 4294967295.

Parameter

Description

Value

priority

Specifies a DR election priority. A larger value indicates a higher priority.

The value is an integer ranging from 0 to 4294967295.

Views

VPN instance PIM view, PIM view of a public network instance

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
pim	write

Usage Guidelines

Usage Scenario

On a PIM-SM shared network segment, a DR is dynamically elected among candidate router interfaces. DR election is based on priorities and IP addresses of interfaces on routers. In a DR election process, routers exchange Hello messages carrying DR election priorities.

If all routers support Hello messages that carry DR election priorities, the interface with the highest DR election priority wins. If all interfaces have the same DR election priority, the interface with the largest IP address wins.
If one or more routers do not support Hello messages that carry DR priorities, the interface with the largest IP address wins.
To change the DR election priority of an interface, run the pim hello-option dr-priority command.

Prerequisites

The multicast routing function has been enabled using the multicast routing-enable command in the public network instance view or VPN instance view.

Configuration Impact

If the hello-option dr-priority command is run more than once, the latest configuration overrides the previous one.

Example

# In the public network instance, set the DR election priority to 3 for the Router.

<HUAWEI> system-view
[~HUAWEI] multicast routing-enable
[*HUAWEI] pim
[*HUAWEI-pim] hello-option dr-priority 3