Example for Configuring IGMP Snooping for a VLAN

This section provides an example for configuring IGMP snooping for a VLAN in typical Layer 2 networking.

Networking Requirements

On the network shown in Figure 1, GE 0/1/0 on DeviceA is connected to an upstream multicast router, DeviceB. DeviceA is connected to Switch-A and Switch-B. Switch-A, Switch-B and the switches connected to them belong to VLAN 3.

If DeviceA does not support IGMP snooping, multicast data traffic will be broadcast to VLANs 2 and 3, wasting network resources.

After IGMP snooping is enabled on DeviceA, multicast data traffic will be sent only to access devices connected to multicast receivers.

In the network with a stable topology, if hosts connected to DeviceA need to receive multicast data for a long period of time, the interface connecting DeviceA to DeviceB can be configured as a router interface.

Figure 1 Example for configuring IGMP Snooping for a VLAN

Interfaces 1 through 3 in this example represent GE 0/1/0, GE 0/1/1, and GE 0/1/2, respectively.

Configuration Roadmap

The configuration roadmap is as follows:

Configure VLANs.
Configure basic IGMP snooping functions.
Configure GE 0/1/0 on DeviceA as a static router port.

Data Preparation

To complete the configuration, you need the following data:

GE 0/1/0 configured as the static router port
VLAN 3 to which Switch-A, Switch-B and the switches connected to them belong

Procedure

Configure VLANs.

<DeviceA> system-view
[~DeviceA] interface gigabitethernet 0/1/1
[~DeviceA-GigabitEthernet0/1/1] portswitch
[*DeviceA-GigabitEthernet0/1/1] undo shutdown
[*DeviceA-GigabitEthernet0/1/1] quit
[*DeviceA] interface gigabitethernet 0/1/2
[*DeviceA-GigabitEthernet0/1/2] portswitch
[*DeviceA-GigabitEthernet0/1/2] undo shutdown
[*DeviceA-GigabitEthernet0/1/2] quit
[*DeviceA] vlan 3
[*DeviceA-vlan3] port gigabitethernet 0/1/1
[*DeviceA-vlan3] port gigabitethernet 0/1/2
[*DeviceA-vlan3] commit
[~DeviceA-vlan3] quit

Enable IGMP snooping on the router.

# Enable global IGMP snooping on DeviceA.

[~DeviceA] igmp-snooping enable

# On DeviceA, enable global IGMP snooping for VLAN 3.

[~DeviceA] vlan 3
[*DeviceA-vlan3] igmp-snooping enable
[*DeviceA-vlan3] commit
[~DeviceA-vlan3] quit

Configure GE 0/1/0 on DeviceA as a static router port.

[~DeviceA] interface gigabitethernet 0/1/0
[~DeviceA-GigabitEthernet0/1/0] portswitch
[*DeviceA-GigabitEthernet0/1/0] undo shutdown
[*DeviceA-GigabitEthernet0/1/0] port link-type access
[*DeviceA-GigabitEthernet0/1/0] port default vlan 3
[*DeviceA-GigabitEthernet0/1/0] igmp-snooping static-router-port vlan 3
[*DeviceA-GigabitEthernet0/1/0] commit
[~DeviceA-GigabitEthernet0/1/0] quit

Verify the configuration.

# Run the display igmp-snooping command on DeviceA.

[~DeviceA] display igmp-snooping vlan configuration
 IGMP Snooping Configuration for VLAN 3
     igmp-snooping enable

# Run the display igmp-snooping router-port vlan 3 command on Device A.

[~DeviceA] display igmp-snooping router-port vlan 3
 Port Name                         UpTime        Expires       Flags
 ---------------------------------------------------------------------
 VLAN 3, 1 router-port(s)
 GigabitEthernet0/1/0            00:01:02      --            STATIC

The preceding command output shows that GE 0/1/0 is configured as a static router port.

Configuration Files

DeviceA configuration file

#
 sysname DeviceA
#
vlan batch 3
#
 igmp-snooping enable
#
vlan 3
 igmp-snooping enable
#
interface GigabitEthernet 0/1/0
 undo shutdown
 portswitch
 port link-type access
 port default vlan 3
 igmp-snooping static-router-port vlan 3
#
interface GigabitEthernet 0/1/1
 undo shutdown
 portswitch
 port default vlan 3
#
interface GigabitEthernet 0/1/2
 undo shutdown
 portswitch
 port default vlan 3
#
return

DeviceB configuration file

#
 sysname DeviceB
#
 multicast routing-enable
#
interface GigabitEthernet 0/1/0
 undo shutdown
ip address 10.1.1.1 255.255.255.252
igmp enable
#
ospf 1
area 0.0.0.0
network 10.1.1.1 0.0.0.3
#
return