Configuration Guide User guide

FastIron Configuration Guide 1615
53-1002494-02
MLD snooping configuration
Because non-queriers always forward multicast data traffic and MLD messages to router ports
which receive MLD queries or IPv6 PIM hellos, Brocade recommends that you configure the devices
with the data traffic source (server) as queriers. If a server is attached to a non-querier, the
non-querier always forwards traffic to the querier regardless of whether or not there are clients on
the querier.
NOTE
In a topology with one or more connected devices, at least one device must be running PIM, or
configured as active. Otherwise, no devices can send queries, and traffic cannot be forwarded to
clients.
To configure the MLD mode (querier or non-querier) on an MLD snooping-enabled device, refer to
“Configuring the global MLD mode” on page 1617. To configure the MLD mode on a VLAN, refer to
“Configuring the MLD mode for a VLAN” on page 1619.
MLD and VLAN configuration
You can configure MLD snooping on some VLANs or all VLANs. Each VLAN can be independently
enabled or disabled for MLD snooping, or can be configured with MLDv1 or MLDv2. In general, the
ipv6 mld-snooping... commands apply globally to all VLANs except those configured with
VLAN-specific mld-snooping... commands. VLAN-specific mld-snooping commands supersede
global ipv6 mld-snooping commands.
MLDv1 with MLDv2
MLD snooping can be configured as MLDv1 or MLDv2 on individual ports on a VLAN. An interface
or router sends queries and reports that include the MLD version with which it has been
configured. The version configuration applies only to the sending of queries. The snooping device
recognizes and processes MLDv1 and MLDv2 packets regardless of the version configured.
NOTE
To avoid version deadlock, when an interface receives a report with a lower version than that for
which it has been configured, the interface does not automatically downgrade the running MLD
version.
MLD snooping configuration
Configuring Multicast Listening Discovery (MLD) snooping on an IPv6 device consists of the
following global and VLAN-specific tasks.
MLD snooping global tasks
• Configuring hardware and software resource limits
• Disabling transmission and receipt of MLD packets on a port
• Configuring the MLD mode: active or passive (must be enabled for MLD snooping)
• Modifying the age interval
• Modifying the interval for query messages (active MLD mode only)
• Specifying the global MLD version
• Enabling and disabling report control (rate limiting)