Adjusting Control Parameters for Assert

If a multicast device can receive multicast data through a downstream interface, this indicates that other upstream devices exist in this network segment. The device then sends an Assert message through the downstream interface to take part in the election of the unique upstream device.

Prerequisites

Before adjusting control parameters for Assert, complete the following tasks:

Configuring a unicast routing protocol
Configuring Basic PIM-DM Functions

Context

When a PIM-DM device receives multicast data through a downstream interface, it indicates that other upstream FWs exist in the network segment. The FW sends Assert messages through the interface to elect the unique upstream FW.

FWs can work normally under the control of the default parameter values. Users can adjust related parameters according to the specific network environment.

The configuration involves the following two cases:

Global configuration: It is valid on each interface.
Configuration on an interface: The configuration on an interface takes precedence over the global configuration. If the configuration on an interface is not done, the global configuration is used.

Procedure

Global Configuration
1. Access the system view.
  system-view
2. Access the PIM view.
  pim [ vpn-instance vpn-instance-name ]
3. Set the period for holding the Assert state.
  holdtime assert interval
  
  The FW that fails in the election prevents its downstream interface from forwarding multicast data.
  
  After the Holdtime of the Assert state expires, the downstream interface can forward packets.
Configuration on an Interface
1. Access the system view.
  system-view
2. Access the interface view.
  interface interface-type interface-number
3. Set the period for holding the Assert state.
  pim holdtime assert interval
  
  The FW that fails in the election prevents its downstream interface from forwarding multicast data. After the Holdtime period of the Assert state expires, the downstream interface can forward packets.