Fortinet Exam NSE8_812 Topic 1 Question 8 Discussion

To ensure that unnecessary multicast traffic is pruned from links that do not have a multicast listener, you must disable IGMP flood traffic on the ICL trunks and enable IGMP flood reports on the ISL and FortiLink trunks.

Disabling IGMP flood traffic will prevent the FortiSwitch units from flooding multicast traffic to all ports on the ICL trunks. This will help to reduce unnecessary multicast traffic on the network.

Enabling IGMP flood reports will allow the FortiSwitch units to learn which ports are interested in receiving multicast traffic. This will help the FortiSwitch units to prune multicast traffic from links that do not have a multicast listener.