Enabling IGMP

Context

IP multicast routing is the prerequisite for all the multicast functions. Enable IP multicast routing before configuring any multicast protocol.

To configure IGMP functions on the switch, first enable IGMP on interfaces connected to group members.

Procedure

Enabling IGMP in the public network instance
1. Run system-view
  The system view is displayed.
2. (Optional) Run set multicast forwarding-table super-mode
  The high-specification mode is configured for multicast forwarding.
  
  In large-scale multicast applications, the switch generates a large number of IGMP group entries. When the number of IGMP group entries reaches the default limit, new IGMP group entries cannot be generated. The high-specification mode increases the number of IGMP group entries supported on the switch. After this mode is configured, the number of IGMP group entries can reach the maximum number supported by the switch, maximizing the switch's capability to support large-scale multicast applications.
  - Only the S5720-HI, S5730-HI, S5731-H, S5731S-H, S5732-H, S6720-HI, S6730S-H, and S6730-H support this command.
  - The configuration of high-specification mode takes effect after a restart.
  - After the high-specification mode is configured, the default value of the robustness variable changes from 2 to 3, the default value of the other querier present interval changes from 125s to 245s, and the default value of the IGMP general query interval changes from 60s to 120s.
3. Run multicast routing-enable
  IP multicast routing is enabled.
  
  By default, the IP multicast routing function is disabled.
4. Run interface interface-type interface-number
  The interface view is displayed.
5. (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.
6. Run igmp enable
  IGMP is enabled on the interface.
  
  By default, IGMP is disabled on an interface.
Enabling IGMP in a virtual private network (VPN) instance
A VPN instance must exist before you enable IGMP in the VPN instance.
1. Run system-view
  The system view is displayed.
2. (Optional) Run set multicast forwarding-table super-mode
  The high-specification mode is configured for multicast forwarding.
3. Run ip vpn-instance vpn-instance-name
  The VPN instance view is displayed.
4. Run ipv4-family
  The IPv4 address family is enabled for the VPN instance, and the VPN instance IPv4 address family view is displayed.
5. Run route-distinguisher route-distinguisher
  An RD is configured for the VPN instance IPv4 address family.
6. Run multicast routing-enable
  IP multicast routing is enabled.
  
  By default, the IP multicast routing function is disabled.
7. Run quit
  Return to the VPN instance view.
8. Run quit
  Return to the system view.
9. Run interface interface-type interface-number
  The interface view is displayed.
  
  When configuring multi-instance IGMP, you can bind VLANIF interfaces, sub-interfaces, loopback interfaces, or tunnel interfaces to VPN instances. The physical interfaces that have been switched to the Layer 3 mode using the undo portswitch command cannot be bound to VPN instances.
10. Run ip binding vpn-instance vpn-instance-name
  The interface is bound to a specified VPN instance.
  
  By default, an interface is a public network interface that is not associated with any VPN instance.
11. Run igmp enable
  IGMP is enabled on the interface.
  
  By default, IGMP is disabled on an interface.