User's Manual

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518
Users Manual of CS-6306R
In a multicast group, the multicast group information cannot be simultaneously
configured both for a specific source address and for all source addresses. The
command used in the later configuration will be omitted. For example, If you run the
command ip igmp static-group 224.1.1.7 include 192.168.20.168 after the
command ip igmp static-group 224.1.1.7 is executed, the command ip igmp
static-group 224.1.1.7 include 192.168.20.168 will be omitted.
50.3.3.7 IGMP Immediate-leave list configuration example
The following example shows how to set the access list to imme-leave on the interface ethernet 1/0 with the
immediate-leave function and to add the IP address 192.168.20.168 of the IGMP host to the access list. The
configuration ensures that the IGMP host with IP address 192.168.20.168 realizes the immediate-leave
function.
interface ethernet 1/0
ip igmp immediate-leave imme-leave
exit
ip access-list standard imme-leave
permit 192.168.20.168
PIM-DM Configuration 50.4
50.4.1 PIM-DM Introduction
Protocol Independent Multicast Dense Mode (PIM-DM) is a multicast routing protocol in dense mode. By
default, when the multicast source starts to send the multicast data, all network nodes in the domain receive
the data. Therefore, PIM-DM forwards the multicast packets in broadcast-pruning mode. When the multicast
source starts to send data, the switches alongside forward the multicast packets to all PIM-activated
interfaces except the RPF interface. In this way, all network nodes in the PIM-DM domain can receive these
multicast packets. To finish the multicast forwarding, the switches alongside need create the corresponding
multicast routing item (S,G) for group G and its source S. The routing item (S,G) includes the multicast source
address, multicast group address, incoming interface, outgoing interface list, timer and logo.
If there is no multicast group member in a certain network segment, PIM-DM will send the pruning information,
prune the forwarding interface connecting the network segment and then establish the pruning state. The
pruning state corresponds to the timeout timer. When the timer times out, the pruning state turns to be the
forwarding state again and the multicast data can be forwarded along these branches. Additionally, the
pruning state contains information about the multicast source and the multicast group. When the multicast
group member appears in the pruning area, PIM-DM actively sends the graft message to the upper field
without waiting for the pruning state of the upper field to time out, turning the pruning state to the forwarding
state.