Quick Reference Guide

PowerConnect B-Series TI24X Configuration Guide 441
53-1002269-02
IGMP snooping overview
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NOTE
In a topology of one or more connecting devices, at least one device must be running PIM, or
configured as active. Otherwise, none of the devices can send out queries, and traffic cannot be
forwarded to clients.
IGMP snooping enhancements
This section describes the enhancements to IGMP snooping . These features are also supported
on PowerConnect B-Series TI24X devices, except where noted.
Support for IGMP V3 snooping
Refer to “IGMP snooping overview” on page 439.
VLAN-specific configuration
IGMP snooping can be enabled on some VLANs or on all VLANs. Each VLAN can be independently
configured to be a quierier or non-quierier and can be configured for IGMP V2 or IGMP V3. In
general, the ip multicast commands apply globally to all VLANs except those configured with
VLAN-specific multicast commands. The VLAN-specific multicast commands supersede the global
ip multicast commands.
IGMP snooping can be configured for IGMP V2 or IGMP V3 on individual ports of a VLAN. An
interface or router sends the queries and reports that include its IGMP version specified on it. The
version configuration only applies to sending queries. The snooping device recognizes and
processes IGMP V2 and IGMP V3 packets regardless of the version configuration.
To avoid version deadlock, an interface retains its version configuration even when it receives a
report with a lower version.
Tracking and fast leave
Devices support fast leave for IGMP V2, and tracking and fast leave for IGMP V3. Fast leave stops
the traffic immediately when the port receives a leave message. Tracking traces all IGMP V3
clients. Refer to “IGMP V3 membership tracking and fast leave” on page 452 and “Fast leave for
IGMP V2” on page 452.
Configuration notes and feature limitations for
PowerConnect B-Series TI24X devices
The following details apply to PowerConnect B-Series TI24X devices:
• Servers (traffic sources) are not required to send IGMP memberships.
• The default IGMP version is V2.
• Hardware resource is installed only when there is data traffic. If a VLAN is configured for
IGMPv3, the hardware matches (S G), otherwise it matches (* G).
• A user can configure the maximum numbers of groups and hardware switched data streams.
• The device supports static groups that apply to the entire VLAN, or to just a few ports. The
device acts as a proxy to send IGMP reports for the static groups when receiving queries.