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GS300 multicast over trunk link

I'm having difficulty in receiving multicast traffic over a trunk link. My IPTV network is shown below. I have 2 x Cisco GS300 switches in Layer 3 mode. I have created a Trunk link between the two switches The top switch is what we would refer to as the Designated Switch (although the GS300 doesn't seem to allow any direct commands that include PIM) and has the IPTV multicast server directly connected. The bottom switch has a couple of VLANs 10 and 20 which represent two separate departments that require access to the multicast IPTV network. IP routing is perfect and a pc in ether of these vlans can ping any other device including all links and the multicast server. However, no multicast traffic reaches the STB in vlan 10 or can be viewed on the PC using VLC.

IGMP is enabled for vlan 10, 20 and the trunk link 2. and as shown all VLANS have been allowed to pass through the trunk interfaces.

If I create VLAN 2 on the bottom switch and give it an IP address of and then put int gig 1 on vlan 252 then the multicast is received at the STB and VLC PC, even with the PC remaining as, so I guess this is inter vlan trunking in a way but I am then unable to ping anything on the network. My problem is we also have security cameras we want to have access in vlan 10 and 20 which are on a separate switch (not shown) an given that it seems that a port can only be a member of one vlan how do you get more than one service to a vlan? Also as I can no longer ping any device vlan 10 and 20 no longer communicate with each other so if I create a new vlan (40) and connect a NAS to it nothing will see it.

In short can I keep port 1 as vlan 10 and port 2 as vlan 20 and have both Multicast from vlan 252 on the other side of the trunk link and our Camera feeds which I will create a trunk link to later?

I hope I have not confused you guys too much, this is my first question ever so you can imagine how frustrated I am.

Thank you in advance,

Kind regards,


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