Configuring IGMP Snooping on EX Series Switches (NSM Procedure)

IGMP snooping regulates multicast traffic in a network. With IGMP snooping enabled, a LAN switch monitors the IGMP transmissions between a host (a network device) and a multicast router, keeping track of the multicast groups and associated member ports. The switch uses that information to make intelligent multicast-forwarding decisions and forward traffic to the intended destination interfaces.

You can configure IGMP snooping on one or more VLANs to allow the switch to examine IGMP packets and make forwarding decisions based on packet content. By default, IGMP snooping is disabled on a device.

Note: When IGMP snooping is enabled on a VLAN, traffic for a given group is flooded to all member ports until IGMP snooping discovers at least one member of the group in the given VLAN.

To enable IGMP snooping and configure individual options:

  1. In the navigation tree, select Device Manager > Devices. In Device Manager, select the device for which you want to configure a port mirror analyzer.
  2. In the Configuration tree, expand Protocols.
  3. Select IGMP Snooping > Vlan.
  4. Click the Add icon.
  5. Add/modify member settings for the interface as specified in Table 60.

Note: After you make changes to a device configuration, you must push that updated device configuration to the physical security device for those changes to take effect. You can update multiple devices at one time. See Updating Devices for more information.

Table 60: IGMP Snooping Configuration Fields



Your Action


Specifies the VLAN for which IGMP snooping is being enabled.

Click Add and select Port or VLAN. Next, select the interfaces or VLANs.

Query Interval

Specifies the query interval on the VLAN.

Select a value.

Query Last Member Interval

Specifies the last member query interval on the VLAN.

Select a value.

Query Response Interval

Specifies the query response interval on the VLAN.

Select a value.

Robust Count

Specifies the number of timeout intervals the switch waits before timing out a multicast group.

Select a value.

Immediate Leave

Immediately removes a multicast group membership from an interface when it receives a leave message from that interface and suppress the sending of any group-specific queries for the multicast group

Select the option to enable it.


Statically configure an interface as a switching interface toward a multicast router (the interface to receive multicast traffic).

  1. Select the VLAN.
  2. Select the option Multicast Router Interface.
  3. Select Static > Group.
  4. Specify the group name to configure IGMP group membership on a port.