Dell PowerConnect 8024 User Configuration Manual page 739

Multicast Source directly connected to Multicast Router, and Listener
connected to a different routing VLAN via intermediate snooping switches:
Server A Client F
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Clients A, D and F are in the same subnet VLAN20 - 192.168.20.70/24. Server
A is in a different subnet VLAN10 – 192.168.10.70/24.
1 Client F sends a report for 239.20.30.40.
2 A multicast forwarding entry is created on D2 VLAN20, 239.20.30.40 –
1/0/20, PortChannel1.
3 The Client F report message is forwarded to D3-PortChannel1 (multicast
router attached port).
4 A multicast forwarding entry is created on D3 VLAN 20, 239.20.30.40 –
PortChannel1, 1/0/20.
5 The Client F report message is forwarded to D4 via D3 – 1/0/20 (multicast
router attached port).
6 An IP multicast routing entry is created on D4 VLAN 10 – VLAN 20 with
the L3 outgoing port list as VLAN 20 – 1/0/20.
7 The multicast stream is routed to D3.
8 The multicast stream is forwarded to listener Client F using forwarding
entries created on D3 and D2.
9 Clients A and D do not receive the Server A multicast stream because they
did not send a report.
Multicast Source connected to Multicast Router via intermediate snooping
switches, and Listener directly connected to multicast router in a different
routing interface: Server B
Server A and Clients B, C, and E are on the same subnet
VLAN10 – 192.168.10.70/24. Server B is in a different subnet
VLAN20 – 192.168.20.70/24.
1 Client B sends a report for 239.20.30.42.
2 Multicast Router D4 learns group 239.20.30.42 but cannot identify the
source because Server B traffic is dropped by D1 and D3 as it is not a
registered group for the snooping switches.
3 Client B cannot receive traffic from Server B.
Client B
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Configuring L2 Multicast Features
739