Configuring Dropping Unknown Multicast Packets; Tracing A Multicast Path; Displaying And Maintaining Common Multicast Configuration - 3Com 5500-EI PWR Install Manual

If the multicast MAC address entry to be created already exists, the system gives you a prompt.
If you want to add a port to a multicast MAC address entry created through the mac-address
multicast command, you need to remove the entry first, create this entry again, and then add the
specified port to the forwarding ports of this entry.
You cannot configure a multicast MAC address starting with 01005e on a device with XRN Fabric
enabled.
You cannot enable link aggregation on a port on which you have configured a multicast MAC
address, and you cannot configure a multicast MAC address on an aggregation port.
You cannot
IGMP-Snooping-enabled VLAN. You can do that if IGMP Snooping is not enabled in the VLAN.

Configuring Dropping Unknown Multicast Packets

Generally, if the multicast address of the multicast packet received on the switch is not registered on the
local switch, the packet will be flooded in the VLAN which the multicast packet belongs to. When the
function of dropping unknown multicast packets is enabled, the switch will drop any multicast packets
whose multicast address is not registered. Thus, the bandwidth is saved and the processing efficiency
of the system is improved.
Follow these steps to configure dropping unknown multicast packet:
To do...
Enter system view
Configure dropping unknown
multicast packets

Tracing a Multicast Path

You can run the mtracert command to trace the path down which the multicast traffic flows from a given
first-hop router to the last-hop router.
To do...
Trace a multicast path

Displaying and Maintaining Common Multicast Configuration

The information about the multicast forwarding table is mainly used for debugging. Generally, you can
get the required information by checking the core multicast routing table.
Three kinds of tables affect multicast data transmission. Their correlations are as follows:
Each multicast routing protocol has its own multicast routing table, such as PIM routing table.
The information of different multicast routing protocols forms a general multicast routing table.
configure a multicast
Use the command...
system-view
unknown-multicast drop
enable
Use the command...
mtracert source-address
[ [ last-hop-router-address ]
group-address ]
MAC address starting
—
Required
By default, the function of
dropping unknown multicast
packets is disabled.
Required
Available in any view
5
with 01005e in an
Remarks
Remarks