How to close the return of the multicast on port 3750?

Question

Cisco

There is a Cisco 3750, on the Gi1 / 0/1 port we receive a multicast from the customer, but at the same time it takes 80 Mbit of a third-party multicast to send it, which it does not even ask for in the logs, how to close the return of multicast groups on the switchport?
Snooping enabled

Answer 1

If the task is to block all outgoing multicast (multicast) traffic in general, try the command switchport block multicaston the interface. Documentation .
UPD :

This command cuts down multicast to all ports from unknown poppies, in my case it does not help at all.

I'm sorry, I overlooked the word unknown in the description (in fairness, 'unknown multicast', as far as I know, does not mean broadcast traffic with an unknown L2 source address, but something else).

Snooping enabled

If there is no multicast router in the network, the ip igmp snooping querier function should be activated so that, roughly speaking, the switch has something to 'snoop'.

Answer 2

You can ACL. You can filter the join at the IGMP level by specific groups. An example is here .