Multicast Listener Discovery (MLD) Snooping Configuration on ESW2-350G Switches

Objective

Multicast is the network layer technique used to transmit data packets from one host to the selected hosts in a group of hosts. At the lower layer, the switch broadcasts the multicast traffic on all ports, even if only one host wants to receive it. Multicast Listener Discovery (MLD) Snooping is used to forward IPv6 multicast traffic only to the desired host.

When MLD snooping is enabled on the switch, it detects the MLD messages exchanged between the IPv6 router and the multicast hosts attached on the interface and maintains a table that restricts IPv6 multicast traffic dynamically to forward only to those ports that want to receive it. Bridge Multicast Filtering and MLD Snooping must be enabled on the switch to perform MLD Snooping.

This article explains how to configure MLD snooping on ESW2-350G Switches.

Applicable Devices

• ESW2-350G
• ESW2-350G-DC

Software Version

• 1.3.0.62

Configuration of MLD Snooping

Enable MLD Snooping

Step 1. Log in to the web configuration utility and choose Multicast > MLD Snooping. The MLD Snooping page opens:

Step 2. Check the Enable check box in the MLD Snooping Status field to allow the switch to determine the hosts that have requested to receive multicast traffic.

Step 3. Click Apply to save the settings.

Edit MLD Snooping Table

Step 1. Log in to the web configuration utility and choose Multicast > MLD Snooping. The MLD Snooping page opens:

Note: MLD Snooping is allowed only on a static VLAN (a VLAN that is manually configured by VLAN ID and port assignments) and not on a dynamic VLAN (a VLAN that is dynamically assigned to the host by the switch when it gets connected. This operation requires the physical addresses of the hosts to be stored on the database of the switch in prior).

Step 2. Click the radio button of the desired VLAN ID and click Edit to configure MLD snooping on that VLAN. The Edit MLD Snooping window appears:

Step 3. (Optional) Choose the desired VLAN ID from the VLAN ID drop-down list.

Step 4. Check the Enable check box in the MLD Snooping Status field to determine which hosts under the chosen VLAN have requested to send the multicast traffic. 

Step 5. (Optional) Check the Enable check box in the MRouter Ports Auto Learn field to automatically learn the ports in the VLAN to which the multicast router is connected. 

Step 6. In the Query Robustness field, enter the robustness value, that ranges from 1 to 7, to indicate the number of MLD queries that the switch sends before it deletes a host that does not respond.

Step 7. In the Query Interval field, enter the time interval, that ranges from 30 to 18000 seconds, after which the switch sends the query messages. 

Step 8. In the Query Max Response Interval field, enter the delay which is used to determine the maximum response code inserted into the general queries. The time ranges from 5 to 20 seconds.

Step 9. Click the desired radio button in the Last Member Query Counter field to define the number of group-specific query messages are sent before the switch assumes that there are no members of the host group to query on the interface.

• Use Default — The value equals to the value defined in the Query Robustness field.

• User Defined — Enter the desired value, that ranges from 1 to 7, in the User Defined field.

Step 10. In the Last Member Query Interval field, enter the time interval for the switch to wait to receive a response from a group-specific message. The time ranges from 100 to 25500 ms.

Step 11. (Optional) Check the Enable check box in the Immediate Leave field to decrease the time taken by the switch to block the MLD traffic that does not belong to its port.

Note: The non-configurable fields on the right show the current configuration for Multicast Listener Discovery snooping.

Step 12. Click Apply.