Multicast Vlan Configuration Task List; Configuring A Sub-Vlan-Based Multicast Vlan; Configuration Prerequisites; Configuration Restrictions And Guidelines - HP FlexFabric 5950 series Configuration Manual

Forward transmission and reverse transmission
The device supports both forward transmission and reverse transmission for multicast VLAN.
In forward transmission, multicast receivers are connected to downstream devices of a Layer 2
device. The Layer 2 device forwards multicast traffic only from the upstream Layer 3 device to
downstream devices that are in sub-VLANs or have member ports.
In reverse transmission, multicast sources are connected to downstream devices of a Layer 2
device. Upon receiving multicast traffic from a downstream multicast source, the Layer 2 device
changes the user VLAN of the traffic to the associated multicast VLAN. Then, it floods the traffic to
the upstream Layer 3 device through the multicast VLAN. The upstream Layer 3 device forwards the
traffic to receivers based on the associated Layer 3 multicast forwarding entry.

Multicast VLAN configuration task list

Tasks at a glance
(Required.) Perform one of the following tasks:
•

Configuring a sub-VLAN-based multicast VLAN

•
Configuring a port-based multicast
Configuring user port attributes

Assigning user ports to a multicast VLAN

(Optional.) Setting the maximum number of multicast VLAN forwarding entries
When you configure the multicast VLANs, follow these guidelines:
•
If you have configured both a sub-VLAN-based multicast VLAN and a port-based multicast
VLAN on a device, the port-based multicast VLAN configuration takes effect.
•
The multicast VLAN feature does not take effect on secondary VLANs. As a best practice, do
not configure the multicast VLAN feature for secondary VLANs. For more information about
secondary VLANs, see Layer 2
Configuring a sub-VLAN-based multicast VLAN
To configure a sub-VLAN-based multicast VLAN, configure a VLAN as a multicast VLAN, and assign
the VLANs that contain multicast receivers to the multicast VLAN as sub-VLANs.

Configuration prerequisites

Before you configure a sub-VLAN-based multicast VLAN, complete the following tasks:
•
Create VLANs as required.
•
Enable IGMP snooping for the VLAN to be configured as the multicast VLAN, and for the
VLANs to be configured as sub-VLANs.

Configuration restrictions and guidelines

When you configure a sub-VLAN-based multicast VLAN, follow these restrictions and guidelines:
•
The VLAN to be configured as the multicast VLAN must exist.
•
The VLANs to be configured as sub-VLANs of the multicast VLAN must exist and cannot be
multicast VLANs or sub-VLANs of any other multicast VLAN.
•
The total number of multicast VLANs on a device cannot exceed the upper limit.
VLAN:
—
LAN Switching Configuration Guide.
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