C H A P T E R
11
Configuring MVR
This chapter contains the following sections:
•
Information About MVR, page 125
•
Licensing Requirements for MVR, page 126
•
Guidelines and Limitations for MVR, page 126
•
Default MVR Settings, page 127
•
•
Verifying the MVR Configuration, page 130
Information About MVR
MVR Overview
In a typical Layer 2 multi-VLAN network, subscribers to a multicast group can be on multiple VLANs. To
maintain data isolation between these VLANs, the multicast stream on the source VLAN must be passed to
a router, which replicates the stream on all subscriber VLANs, wasting upstream bandwidth.
Multicast VLAN Registration (MVR) allows a Layer 2 switch to forward the multicast data from a source on
a common assigned VLAN to the subscriber VLANs, conserving upstream bandwidth by bypassing the router.
The switch forwards multicast data for MVR IP multicast streams only to MVR ports on which hosts have
joined, either by IGMP reports or by MVR static configuration. The switch forwards IGMP reports received
from MVR hosts only to the source port. For other traffic, VLAN isolation is preserved.
MVR requires at least one VLAN to be designated as the common VLAN to carry the multicast stream from
the source. More than one such multicast VLAN (MVR VLAN) can be configured in the system, and you
can configure a global default MVR VLAN as well as interface-specific default MVR VLANs. Each multicast
group using MVR is assigned to an MVR VLAN.
MVR allows a subscriber on a port to subscribe and unsubscribe to a multicast stream on the MVR VLAN
by sending IGMP join and leave messages. IGMP leave messages from an MVR group are handled according
to the IGMP configuration of the VLAN on which the leave message is received. If IGMP fast leave is enabled
Cisco Nexus 6000 Series NX-OS Layer 2 Switching Configuration Guide, Release 7.x
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