H3C Technologies H3C SecPath F1000-E - Manual (Page 51)

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To do… Use the command… Remarks
Enable the IGMP proxying
feature
igmp proxying enable
Required
Disabled by default.
NOTE:
•
Each device can have only one interface serving as the proxy interface.
• You cannot enable IGMP on an interface with IGMP proxying enabled. Moreover, only the igmp
require-router-alert, igmp send-router-alert, and igmp version commands can take effect on such an
interface.
• You cannot enable other multicast routing protocols (such as PIM-DM or PIM-SM) on an interface with
IGMP proxying enabled, or vice versa. However, the source-lifetime, source-policy, and ssm-policy
commands configured in PIM view can still take effect. In addition, in IGMPv1, the designated router
(DR) is elected by the working multicast routing protocol (such as PIM) to serve as the IGMP querier.
Therefore, a downstream interface running IGMPv1 cannot be elected as the DR and thus cannot serve
as the IGMP querier.
Configuring Multicast Forwarding on a Downstream Interface
Typically, only queriers are able to forward multicast traffic while non-queriers have no multicast
forwarding capabilities, to avoid duplicate multicast flows. It is the same on IGMP proxy devices. Only
the downstream interfaces acting as a querier can forward multicast traffic to downstream hosts.
However, when a downstream interface of a proxy device fails to win the querier election, you must
enable multicast forwarding on this interface.
Follow these steps to enable multicast forwarding on a downstream interface
To do… Use the command… Remarks
Enter system view system-view —
Enter interface view
interface interface-type
interface-number
—
Enable multicast forwarding on a
non-querier downstream interface
igmp proxying forwarding
Required
Disabled by default.
CAUTION:
On a multi-access network with more than one IGMP proxy device, you cannot enable multicast
forwarding on any other non-querier downstream interface after one of the downstream interfaces of
these IGMP proxy devices has been elected as the querier. Otherwise, duplicate multicast flows may be
received on the multi-access network.