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New Member

dlna, multicast forwarding

i have a dlna server on one VLAN, and i want to forward the multicast traffic to other VLANs so clients on those VLANs can subscribe to the streams and consume the media.  i have a sg300-28, and a linux machine running as a router.  the router has IGMPproxy installed and should be able to forward the IGMP multicast traffic, but it seems that both layer 2 and layer 3 need to be in on the effort to get everything working.  am i correct in thinking that?

what would i need to configure on the switch to get the dlna multicast traffic sent to ports on other VLANs?  do i need both layer 2 and layer 3 to participate in the effort?

thanks in advance.

New Member

dlna, multicast forwarding


You can't select Layer 2 and Layer 3. In Layer 3 mode the device handles InterVLAN communication for the VLANs that are configured on it with no problems. As for the Multicasting, you might want to check the "Multicast" tab and look at some of those configurations. If you run it in Layer 2 mode then the router will have to handle all the InterVLAN communications.

I hope this helps. If you need farther assistance do not hesitate to call us at Cisco Small Business Support - 1(866)606-1866

Richard Pruitt

New Member

dlna, multicast forwarding

i dont understand what you mean about selecting layer 2 and layer 3.  the switch is in layer 2 mode, and i have a separate device doing layer 3.  the layer 3 device is running a service to forward multicast traffic and that does not seem to be enough.  i am looking to see if the multicast functionality of the layer 2 device needs to be used to get everything working.  i am refering to IGMP snooping and those features of the switch.


Re: dlna, multicast forwarding

Hi Brendan, as it should work, you can enable bridge multicast filtering then you need to choose mac or ip group.Once that decision is made you can enable the switch as a querier or not through the IGMP snooping

Depending if you choose mac or IP group you should dynamically see the devices in the respective section mac group address or the ip multicast group address. This is particularly true through the IGMP snooping feature set.

It's one of those things you have to tinker with to make it work, I don't think you'll get a definitive answer.

If you want to test if multicast works at all, you can choose to flood it out every port (without the filtering).

To answer about the vlans, it is still a layer 2 operation, you would need a layer 3 device to route the vlans which I am assuming you have a layer 3 capable device somewhere that can allow the packets to route. While the IGMP of the switch will forward multicast packet to their respective group based off the packet info and what it learns in the tables.

Please mark answered for helpful posts

-Tom Please mark answered for helpful posts