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IGMP snooping

Internet group management protocol (IGMP) snooping is a method that network switches use to identify IPv4 multicast groups. With IGMP snooping turned on, the switch creates a list of ports that receive multicast data. The switch only forwards multicast data to those ports.

Settings

Go to My Products > Switches > Switches, select the switch or site where you want to configure IGMP snooping, and go to L3 protocols > IGMP snooping > Settings to configure the IGMP snooping.

Status turns IGMP snooping on or off globally for the switch or site.

Select Enabled or Disabled to turn IGMP snooping on or off.

Select Not set to use the IGMP snooping status configured locally on the switch.

Report suppression limits the number of membership reports the member sends to multicast-capable routers. Enter a value from 1 to 25.

Click Save to update your settings.

Configuration source shows the origin of the IGMP snooping settings.

You can see the IGMP snooping settings for each of the VLANs configured on the switch. Click edit Edit. to change the settings for the selected VLAN. You can change the following settings:

  • Status: Turns IGMP snooping on or off for the selected VLAN. Select one of the following statuses:

    • Enabled: Turn IGMP snooping on.
    • Disabled: Turn IGMP snooping off.
    • Not set: Use the IGMP snooping status configured locally on the switch.

  • Version: Select the IGMP version to use from the following options:

    • v1: IGMPv1.
    • v2: IGMPv2.
    • v3: IGMPv3.
    • Not set: Use the IGMP version configured locally on the switch.

  • Querier status: The IGMP snooping querier sends IGMP queries that trigger IGMP report messages from connected devices wanting to receive IP multicast traffic. IGMP snooping uses these reports to establish correct forwarding. Select from the following options:

    • Enabled: Turn the IGMP snooping querier on.
    • Disabled: Turn the IGMP snooping querier off.
    • Not set: Use the IGMP snooping querier status configured locally on the switch.

  • Fast leave: When turned on, the switch considers the port to have only one endpoint attached. This can improve bandwidth usage for a network that frequently experiences many IGMP host add and leave requests.

    • Enabled: Turn Fast leave on.
    • Disabled: Turn Fast leave off.
    • Not set: Use the Fast leave status configured locally on the switch.

  • Querier interval (seconds): Sets the time between general query transmissions. Enter a value from 60 to 600.

  • Response interval (seconds): Sets the time hosts must respond to IGMP queries within. Enter a value from 0 to 25.
  • Startup query counter: Sets the number of IGMP queries the switch sends out at the rate set by the Startup query interval. Enter a value from 2 to 5.
  • Startup query interval (seconds): Sets the rate at which the switch sends IGMP membership queries after it starts up. Enter a value from 15 to 150.
  • Static ports: Select the ports connected to multicast-enabled routers from the drop-down list.

Click Save to save your changes to the VLAN settings.

Group list

The Group list tab shows the list of discovered multicast groups. These groups of computers or devices receive the same network traffic.