27
•
Enable IGMP snooping in the VLAN
•
Determine the ACL rules for multicast group filtering
•
Determine the maximum number of multicast groups that can pass the ports
•
Determine the 802.1p precedence for IGMP messages
Configuring a multicast group filter
On an IGMP snooping–enabled switch, a multicast group filter enables the service provider to define
restrictions on multicast programs available to different users.
In an actual application, when a user requests a multicast program, the user's host initiates an IGMP
report. Upon receiving this report message, the switch checks the report against the configured ACL
rule. If the port on which the report was received can join this multicast group, the switch adds an
entry for this port in the IGMP snooping forwarding table. Otherwise the switch drops this report
message. Any multicast data that has failed the ACL check will not be sent to this port. In this way,
the service provider can control the VOD programs provided for multicast users.
Configuring a multicast group filter globally
Follow these steps to configure a multicast group filter globally:
To do...
Use the command...
Remarks
Enter system view
system-view
—
Enter IGMP snooping view
igmp-snooping
—
Configure a multicast group filter
group-policy
acl-number
[
vlan
vlan-list
]
Required
By default, no group filter is
globally configured. The hosts in a
VLAN can join any valid multicast
group.
Configuring a multicast group filter on a port or a group of ports
Follow these steps to configure a multicast group filter on a port or a group of ports:
To do...
Use the command...
Remarks
Enter system view
system-view
—
Enter Ethernet interface/Layer 2
aggregate interface view or port
group view
interface
interface-type
interface-number
Required
Use either approach
port-group
manual
port-group-name
Configure a multicast group filter
igmp-snooping group-policy
acl-number
[
vlan
vlan-list
]
Required
By default, no group filter is
configured on the current port.
The hosts on this port can join any
valid multicast group.
Configuring multicast source port filtering
With the multicast source port filtering feature enabled on a port, the port can be connected with
multicast receivers only rather than with multicast sources, because the port will block all multicast
data packets but it permits multicast protocol packets to pass.
If this feature is disabled on a port, the port can be connected with both multicast sources and
multicast receivers.