Adjusting Time Parameters for Join/Prune Messages

Context

A PIM device periodically sends Join/Prune messages to an upstream device to update the forwarding state. When the upstream device receives a Join/Prune message, it starts a timer and sets the timer value to the holdtime of the Join/Prune message. If the device does not receive any Join/Prune message when the timer expires, it acts as follows:

If the previously received Join/Prune message is sent by a host to join a multicast group, the device stops sending multicast data to the downstream interface of the multicast group.
If the previously received Join/Prune message is sent to prune the downstream interface of a multicast group, the device starts to send multicast data packets to the downstream interface.

Therefore, the interval for sending Join/Prune messages must be smaller than the holdtime of a Join/Prune message.

The interval for sending Join/Prune messages and the holdtime of Join/Prune messages can be set globally or on an interface. If you configure the two parameters in the global PIM-IPv6 view and in the interface view simultaneously, the configuration in the interface view takes effect.

Default Settings

Table 1 lists the default settings of time parameters for Join/Prune messages.

**Table 1** Default settings of time parameters for Join/Prune messages
Parameter	Default Setting
Interval for sending Join/Prune messages	60s
Holdtime of Join/Prune messages	210s

Procedure

Global configuration
1. Run system-view
  The system view is displayed.
2. Run pim-ipv6
  The PIM-IPv6 view is displayed.
3. Run timer join-prune interval
  The interval for sending Join/Prune messages is configured.
4. Run holdtime join-prune interval
  The holdtime of Join/Prune messages is configured.
Configuration on an interface
1. Run system-view
  The system view is displayed.
2. Run interface interface-type interface-number
  The interface view is displayed.
3. (Optional) On an Ethernet interface, run undo portswitch
  The interface is switched to Layer 3 mode.
  
  By default, an Ethernet interface works in Layer 2 mode.
  
  Only the S5720-EI, S5720-HI, S5730-HI, S5731-H, S5731-S, S5731S-H, S5731S-S, S5732-H, S6720-EI, S6720-HI, S6720S-EI, S6730-H, S6730S-H, S6730-S, and S6730S-S support switching between Layer 2 and Layer 3 modes.
4. Run pim ipv6 timer join-prune interval
  The interval for sending Join/Prune messages is configured.
5. Run pim ipv6 holdtime join-prune interval
  The holdtime of Join/Prune messages is configured.