Turning off IGMP-snooping means that every MC will be sent out on all interfaces within the same vlan. ( like broadcast)
Turning OFF is needed when you have a pure Layer2 Multicast environment und you cannot turn on any multicast Querier. or irb-interface with PIM enabled, or.... ( every vendor has different solutions for pure L2-multicast to overcome that problem) The reason for that is that IGMP is a softstate protocol and the IGMP-querier will check via asking if there are still interested listeners on that LAN, if no answer the multicast stream will be turned off, by the Querier, or if there is no querier it will be turned off by the switch doing IGMP-snooping after timeout ( typically 180 sec) And the behavior is the same for all enterprise switches when they support IGMP-snooping ( not only EX3300) With best regards alexander -----Ursprüngliche Nachricht----- Von: juniper-nsp [mailto:juniper-nsp-boun...@puck.nether.net] Im Auftrag von Gert Doering Gesendet: Dienstag, 9. Januar 2018 09:19 An: juniper-nsp@puck.nether.net Betreff: Re: [j-nsp] Multicast through a switch Hi On Mon, Jan 08, 2018 at 03:51:22PM -0600, Chris Adams wrote: > Now we're trying to pass the feed through a VLAN to a new connection > through a switch (a VLAN on a trunk from our router to a VLAN on > another trunk to the transport carrier), but we're not sure how to get > the switch to pass the traffic. I guess there's something we need to > configure static on the switch, but I don't know what. "just passing through multicast" (as in "same VLAN") should not need any special configuration. OTOH, at least EX3300 like to eat multicast unless you turn off IGMP snooping ("delete protocols igmp-snooping") - which, annoyingly, is on-by-default. Without any "smarts" in the switch, multicast is just like broadcast. gert -- now what should I write here... Gert Doering - Munich, Germany g...@greenie.muc.de _______________________________________________ juniper-nsp mailing list juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp