Configuring IGMP On-Demand
Context
In a standard IGMP working process, the querier periodically sends Query messages and collects group membership information based on Report and Leave messages sent from hosts. If group members on a network seldom change, you can configure IGMP on-demand on the querier. IGMP on-demand enables the querier to maintain group memberships based on hosts' requirements, without sending Query messages. This function reduces the number of IGMP messages exchanged between the querier and hosts, conserving bandwidth on the network.
After you configure IGMP on-demand on an interface of the switch:
- The interface no longer sends IGMP Query messages.
- The switch creates IGMP group entries after receiving IGMP Report messages. The entries will never age out.
- The switch deletes a group entry immediately after receiving an IGMP Leave message for the group.
IGMP on-demand applies only to IGMPv2 and IGMPv3.
Procedure
- Run system-view
The system view is displayed.
- Run interface interface-type interface-number
The interface view is displayed.
- (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.
- Run igmp on-demand
IGMP on-demand is enabled on the interface. The interface no longer sends IGMP Query messages, and IGMP group entries on the interface will never age out.
By default, an interface periodically sends Query messages and participates in querier election.
If dynamic IGMP entries have been generated on the querier, run the reset igmp group command to clear these dynamic IGMP entries before running the igmp on-demand command.