Multicast Forwarding
Configuring MLD Snooping
Cisco 220 Series Smart Switches Administration Guide Release 1.1.0.x
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•
MLDv2 Snooping uses MLDv2 control packets to forward traffic based on
the destination IPv6 Multicast address only
.
It supports the capability to
resolve the MLDv2 control packets.
The actual MLD version is selected by the Multicast router in the network.
In an approach similar to IGMP Snooping, MLD frames are snooped as they are
forwarded by the switch from stations to an upstream Multicast router and vice
versa. This facility enables a switch to conclude the following:
•
On which ports stations interested in joining a specific Multicast group are
located
•
On which ports Multicast routers sending Multicast frames are located
This knowledge is used to exclude irrelevant ports (ports on which no stations
have registered to receive a specific Multicast group) from the forwarding set of an
incoming Multicast frame.
If you enable MLD Snooping in addition to the manually configured Multicast
groups, the result is a union of the Multicast groups and port memberships derived
from the manual setup and the dynamic discovery by MLD Snooping. However,
only the static definitions are preserved when the switch is rebooted.
To enable MLD Snooping:
STEP 1
Click
Multicast
>
MLD Snooping
.
STEP 2
Enter the following information:
•
MLD Snooping Version
—Select either MLDv1 or MLDv2.
•
Report Suppression
—Enable or disable MLD Snooping report suppression.
Disabling this feature will forward all MLDv1 reports to Multicast routers.
STEP 3
Click
Apply
.
STEP 4
Select a VLAN, and click
Edit
.
STEP 5
Enter the following information:
•
VLAN ID
—Select the VLAN ID.
•
MLD Snooping Status
—Enable or disable MLD Snooping on the VLAN. The
switch monitors network traffic to determine which hosts have asked to be
sent Multicast traffic. The switch performs MLD Snooping only when MLD
Snooping is enabled globally and on the VLAN.
