Igmp Querier Commands - NETGEAR GSM7212 - ProSafe Switch Cli Reference Manual

Command Line Interface Reference for the ProSafe 7200 Series Layer-2 Switches, Software Ver-
Type
Description
Interfaces

13.3 IGMP Querier Commands

A switch configured as a querier will send general queries periodically to request group
membership information from an attached network. These queries will invoke client
response that can be used to build and refresh the multicast group membership state of
systems (snooping entries of MFDB table) on the attached networks. Interested hosts shall
respond to these queries by reporting their group membership state and this will result in
creation of snooping entry in MFDB table.
The IGMP querier function supports IGMP Version 2.
The IGMP querier function must be enabled on VLAN basis.
IGMP snooping must be enabled on the switch for the querier function to be enabled.
When a VLAN is configured as a querier, IGMP query packets will be sent on every port,
which is a member of the VLAN. If a multicast router is attached on a port (either detected
dynamically or configured statically by the user) then the IGMP general query packet will
not be sent to that port. A physical port on which IGMP query message is to be sent should
fulfill the following criteria:
• Multicast router is not attached.
• Must not be the probe port of a mirroring session.
• Must not be a LAG member.
• Must not be enabled for routing.
• Must be in the Forwarding state.
The query packets that are sent periodically will have one of the following IP addresses for
the source IP address field:
• VLAN Interface Address (for L3 switches only) 'or'
IGMP Snooping Commands
displayed as a MAC address and VLAN ID combination of 8
bytes.
Displays the type of the entry, which is either static (added by
the user) or dynamic (added to the table as a result of a learn-
ing process or protocol).
The text description of this multicast table entry.
The list of interfaces that are designated for forwarding
(Fwd:) and filtering (Flt:).
v1.0, February 2007
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