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Configuring an MLD snooping policy
This section describes how to configure an MLD snooping policy.
Configuration prerequisites
Before you configure an MLD snooping policy, complete the following tasks:
•
Enable MLD snooping for the VLAN.
•
Determine the IPv6 ACL for IPv6 multicast group filtering.
•
Determine the maximum number of IPv6 multicast groups that a port can join.
•
Determine the 802.1p precedence for MLD messages.
Configuring an IPv6 multicast group filter
On a MLD snooping–enabled switch, you can configure an IPv6 multicast group filter to limit
multicast programs available to different users.
In an application, when a user requests a multicast program, the user's host initiates an MLD report.
After receiving this report message, the switch resolves the IPv6 multicast group address in the
report and looks up the ACL. If a match is found to permit the port that received the report can join
this IPv6 multicast group, the switch creates an MLD snooping forwarding entry for the IPv6 multicast
group and adds the port to the entry. Otherwise, the switch drops this report message, in which case,
the IPv6 multicast data for the IPv6 multicast group is not sent to this port, and the user cannot
retrieve the program.
Configuration guidelines
•
When you configure a multicast group filter in an IPv6 multicast VLAN, be sure to configure the
filter in the sub-VLANs of the IPv6 multicast VLAN. Otherwise, the configuration does not take
effect.
•
In MLDv2, when a host is enabled to join multiple multicast groups, the multicast group filter
cannot correctly filter multicast groups because the host that runs MLDv2 sends multiple
multicast groups that it wants to join in one membership report.
Configuration procedure
To configure an IPv6 multicast group filter globally:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter MLD-snooping view.
mld-snooping
N/A
3.
Configure an IPv6 multicast
group filter.
group-policy
acl6-number
[
vlan
vlan-list
]
By default, no IPv6 group filter is
globally configured, and the hosts
in a VLAN can join any valid IPv6
multicast group.
To configure an IPv6 multicast group filter on a port:
Step Command
Remarks
1.
Enter system view.
system-view
N/A