configuring igmp snooping. Is it worth it? does it work?
Hi,
I have a good understanding of basic networking, vlans, etc. I have a very simple setup with an ISP modem/router huawei hg8245h, unifi Switch and 2 AP Lite.
I have 3 IPTVs on the network. When I turned on igmp snooping in the switch, the cable went down and after checking some logs, the packets were getting discarded of some sort. I know what igmp does and it's supposed to be great for video and streaming, basically multicast.
Had this happened to someone, because unifi support is not much help really.
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FYI. I also tried messing with Vlans to accomplish this, but it quite confused me. As by default everything works. From what I can analyze from the ISP router. I have 4 vlans coming from the wan port as trunk. Internet, IPTV, VoIP and Multicast.
The vlans are not bound to any of the ports. The dhcp for the LAN is using option 125 and all the IPTVs are detected as MSFT_IPTV.
Maybe I'm over complicating things, but hey I'm just explaining the settings to make it easier for someone to help lol
https://en.wikipedia.org/wiki/IGMP_snooping
IGMP Snooping only has impact if you are using multicast applications.
What multicast application(s) are you running?
What do you hope IGMP will do for you?
I have 3 IPTVs
Snooping is therefore especially useful for bandwidth-intensive IP multicast applications such as IPTV.
Benefits: that's why asking what benefits I can get. Because I see it everywhere when you go buy a switch for homes. The use that as marketing. Tplink and netgear as an example.
You might need to make sure the switch has a IGMP “querier” running on it too if your router is not a querier. As far as I understand it there’s two parts to IGMP snooping 1) the snooping which does the filtering and 2) the querier/mrouter which send out igmp reports that all the multicast listeners respond to which keeps the switch from filtering the stream to that port.
No reports then nothing for snooping to snoop and it eventually filters everything.
I think unifi switches are supposed to enable the querier if there is no USG in the network. But for example on edge switches I’m pretty sure you have to manually enable both features or you can get the situation where multicast traffic just eventually gets dropped as nothing is sending out reports.
See if the ubnt forums mention anything about unifi switches and querier.
How can I check if my router is doing igmp querier. Wireshark?
I found exactly what describes my issue. Other home brands allow you configure IPTV service and get around it. But I don't seem to get it working on unifi. There's a huge post in the ubiquiti forums regarding the problem.
Netgear solution - https://kb.netgear.com/29911/Configuring-VLAN-IPTV-setup-on-your-Nighthawk-router
TP-link solution - https://www.tp-link.com/us/support/faq/1546/
Ubiquiti Guide - that doesn't work https://community.ui.com/questions/Guide-VLAN-IPTV-Setup-with-UniFi-Devices-/8e00582f-3c75-4815-983f-a5c7fd0aad2c