HPE 5820X Series, Руководство по настройке

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For more information about the SSM group range, see " Configuring PIM ."
IGMP proxying
In some simple tree-shaped topologies, it is not necessary to configure complex multicast routing
protocols, such as PIM, on the edge devices. Instead, you can configure IGMP proxying on these
devices. With IGMP proxying configured, the device serves as a proxy for the downstream hosts to
send IGMP messages, maintain group memberships, and implement multicast forwarding based on
the memberships. In this case, each boundary device is a host but no longer a PIM neighbor to the
upstream device.
Figure 36 Network diagram
As shown in Figure 36 , an IGMP proxy device has the following types of interfaces:
•
Upstream interface
—Also called the "proxy interface." A proxy interface is an interface on
which IGMP proxying is configured. It is in the direction toward the root of the multicast
forwarding tree. An upstream interface acts as a host that is running IGMP. Therefore, it is also
called the "host interface."
•
Downstream interface
—An interface that is running IGMP and is not in the direction toward
the root of the multicast forwarding tree. A downstream interface acts as a router that is running
IGMP. Therefore, it is also called the "router interface."
A device with IGMP proxying configured maintains a group membership database, which stores the
group memberships on all downstream interfaces. Each entry comprises the multicast address, filter
mode, and source list. Such an entry is a collection of members in the same multicast group on each
downstream interface.
A proxy device performs host functions on the upstream interface based on the database. It
responds to queries according to the information in the database or sends join/leave messages
when the database changes. On the other hand, the proxy device performs router functions on the
downstream interfaces by participating in the querier election, sending queries, and maintaining
memberships based on the reports.
IGMP support for VPNs
IGMP maintains group memberships on a per-interface base. After receiving an IGMP message on
an interface, IGMP processes the packet within the VPN that the interface belongs to. If IGMP that