GS108Ev3 Blocked IGMP packets on TRUNK VLAN whend IGMP snooping enabled for VLAN 1

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urosh wrote:

If a device (Set-top Box or computer) connected to the port 6 sends a tagged IGMP packet (membership report) with VLAN id 3999, then it seems that the packet is blocked on the switch and the device (ISP's modem) connected to the port 8 never gets it.

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As configured in your example to handle IGMP Multicast on the VLAN 1.

 

urosh wrote:

Device on port 6 therefore nevere receives IPTV multicast stream from the modem. Modem's port is configured to a TRUNK profile: LAN + IPTV (native untagged LAN + tagged IPTV).

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Only one VLAN is supported - according to the configuration - to handle IGMP Multicast on these non-managed configurable core switches coming at a price tag of a non-managed quality brand switch.

 

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urosh wrote:

If I change "VLAN ID Enabled for IGMP Snooping" from 1 to 3999, it starts working, but then then multicasting on VLAN 1 stops working - untagged IGMP packets (e.g. from port 7) are never delivered to the port 8 (VLAN 1).

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Exactly as specified, documented and tested.

 

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urosh wrote:

I would expect that multicasting on both VLANS (tagged and untagged) would work independently of each other.

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Multicast - which is clearly not the same like IGMP Multicast - does continue to work on all VLANs. UPnP SSDP (a typical example of basic Multicast) can reach all destinations ports and VLANs. If you however expect IGMP Multicast on select or all VLANs configured, you need to invest a few Dollars more.

 

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urosh wrote:

If I disable IGMP snooping, then multicasting works on both VLANs as expected.

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Wrong. IGMP Snooping is not active, the IGMP Multicast will be flooded to all ports and VLANs, obsoleting the advantage of IGMP Multicast.

 

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urosh wrote:

On another brand switch this configuration worked without any problems.

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This is not a brand limitation, the same capability is available on Netgear's Smart Managed switch model lines (and up), too.