Configuring Igmp Filtering - Cisco Catalyst 2950 Software Configuration Manual

Configuring IGMP Filtering

This example shows the results of the show mvr interface privileged EXEC command when the
members keyword is included:
Switch# show mvr interface gigabitethernet0/1 members
239.255.0.0
239.255.0.1
239.255.0.2
239.255.0.3
239.255.0.4
239.255.0.5
239.255.0.6
239.255.0.7
239.255.0.8
239.255.0.9
This example shows the results of the show mvr members privileged EXEC command:
Switch# show mvr members
MVR Group IP
------------
239.255.0.1
239.255.0.2
239.255.0.3
239.255.0.4
239.255.0.5
239.255.0.6
239.255.0.7
239.255.0.8
239.255.0.9
239.255.0.10
<output truncated>
239.255.0.255
239.255.1.0

Configuring IGMP Filtering

In some environments, for example metropolitan or multiple-dwelling unit (MDU) installations, an
administrator might want to control the set of multicast groups to which a user on a switch port can
belong. This allows the administrator to control the distribution of multicast services, such as IP/TV,
based on some type of subscription or service plan. 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.
IGMP filtering controls only IGMP queries and membership join reports and 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.
You can also set the maximum number of IGMP groups that an interface can join.
Catalyst 2950 Desktop Switch Software Configuration Guide
16-18
DYNAMIC ACTIVE
DYNAMIC ACTIVE
DYNAMIC ACTIVE
DYNAMIC ACTIVE
DYNAMIC ACTIVE
DYNAMIC ACTIVE
DYNAMIC ACTIVE
DYNAMIC ACTIVE
DYNAMIC ACTIVE
DYNAMIC ACTIVE
Status Members
------ -------
ACTIVE Gi0/1(d), Gi0/5(s)
INACTIVE None
INACTIVE None
INACTIVE None
INACTIVE None
INACTIVE None
INACTIVE None
INACTIVE None
INACTIVE None
INACTIVE None
INACTIVE None
INACTIVE None
Chapter 16 Configuring IGMP Snooping and MVR
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