Cisco IE 4000, Руководство по настройке программного обеспечения

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Configuring IGMP Snooping and MVR
Information About IGMP Snooping and MVR
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MVR data received on an MVR receiver port is not forwarded to MVR source ports.
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MVR does not support IGMPv3 messages.
IGMP Filtering and Throttling
In some environments, for example, metropolitan or multiple-dwelling unit (MDU) installations, you might want to control
the set of multicast groups to which a user on a switch port can belong. You can control the distribution of multicast
services, such as IP/TV, based on some type of subscription or service plan. You might also want to limit the number of
multicast groups to which a user on a switch port can belong.
With the IGMP filtering feature, you can filter multicast joins on a per-port basis by configuring IP multicast profiles and
associating them with individual switch ports. An IGMP profile can contain one or more multicast groups and specifies
whether access to the group is permitted or denied. If an IGMP profile denying access to a multicast group is applied to
a switch port, the IGMP join report requesting the stream of IP multicast traffic is dropped, and the port is not allowed to
receive IP multicast traffic from that group. If the filtering action permits access to the multicast group, the IGMP report
from the port is forwarded for normal processing. You can also set the maximum number of IGMP groups that a Layer 2
interface can join.
IGMP filtering controls only group-specific query and membership reports, including join and leave reports. It does not
control general IGMP queries. IGMP filtering has no relationship with the function that directs the forwarding of IP
multicast traffic. The filtering feature operates in the same manner whether CGMP or MVR is used to forward the multicast
traffic.
IGMP filtering is applicable only to the dynamic learning of IP multicast group addresses, not static configuration.
With the IGMP throttling feature, you can set the maximum number of IGMP groups that a Layer 2 interface can join. If
the maximum number of IGMP groups is set, the IGMP snooping forwarding table contains the maximum number of
entries, and the interface receives an IGMP join report, you can configure an interface to drop the IGMP report or to
replace the randomly selected multicast entry with the received IGMP report.
Note: IGMPv3 join and leave messages are not supported on switches running IGMP filtering.
Default IGMP Filtering and Throttling Configuration
When the maximum number of groups is in forwarding table, the default IGMP throttling action is to deny the IGMP report.
IGMP Profiles
To configure an IGMP profile, use the ip igmp profile global configuration command with a profile number to create an
IGMP profile and to enter IGMP profile configuration mode. From this mode, you can specify the parameters of the IGMP
profile to be used for filtering IGMP join requests from a port. When you are in IGMP profile configuration mode, you can
create the profile by using these commands:
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deny —Specifies that matching addresses are denied; this is the default.
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exit —Exits from igmp-profile configuration mode.
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no —Negates a command or returns to its defaults.
Feature Default Setting
IGMP filters None applied
IGMP maximum number of IGMP groups No maximum set
IGMP profiles None defined
IGMP profile action Deny the range addresses