Multicast Listener Discovery (MLD) is a Layer 3 multicast protocol used between IPv6 hosts, and routers similar to how IGMP is used for IPv4. MLD snooping allows a switch to examine MLD packets, and make forwarding decisions based on their content.

MLD snooping constrains IPv6 multicast traffic at Layer 2 by configuring Layer 2 LAN ports dynamically to forward IPv6 multicast traffic only to those ports that want to receive it.

The default behavior, when you do not configure MLD Snooping, Netvisor forwards multicast traffic to all the switch ports, impacting switch performance.

Syntax   mld-snooping-modify

scope local|fabric

Modify the scope of MLD Snooping to local or fabric.


Enable, disable MLD Snooping. Default: disable

mldv1-vlans vlan-list

VLANs on which to enable snooping, and use MLDv1 protocol. Default: none

mldv2-vlans vlan-list

VLANs on which to enable snooping, and use MLDv2 protocol. Default 1 - 4092

snoop-linklocal-vlans vlan-list

Allow snooping of link-local groups (ff02::/16) on these vlans. Default 1 - 4092

snoop-nd-vlans vlan-list

Allow snooping of ND SN Multicast addresses (ff02::1:ff/104) on these vlans. Default 1 - 4092

query-interval seconds

Specify the interval between queries in seconds.

query-max-response-time seconds

Specify the maximum response time for a query.

Defaults   See above description

Access   CLI


Version 2.3

Command introduced.

Version 2.4

The parameters version and snoop-link introduced.

Version 2.5.2

The parameters version, snoop-linklocal and snoop-nd deprecated.

The parameters mldv1-vlans, mldv2-vlans, snoop-linklocal-vlans, and snoop-nd-vlans introduced.

Version 3.1.0

The parameters query-interval and query-max-response-time added.

Usage   When MLD Snooping is not configured, multicast traffic is forwarded to all the switch ports, impacting switch performance. Use this command to modify the scope of MLD Snooping, enable snooping on specific VLANs, link-local groups, or ND SN multicast addresses, or to disable snooping.

Examples  To modify the scope from local to fabric use the following syntax:

CLI (network-admin@switch) > mld-snooping-modify scope fabric