IGMP Configuration Summary show igmp enable
9-2 IGMP Configuration
However,notethatIGMPneitheraltersnorroutesanyIPmulticastpackets.SinceIGMPisnot
concernedwiththedeliveryofIPmulticastpacketsacrosssubnetworks,anexternalIPmulticast
switchdeviceisneededifIPmulticastpacketshavetoberoutedacrossdifferentsubnetworks.

IGMP Configuration Summary

Multicastingisusedtosupportrealtimeapplicationssuchasvideoconferencesorstreaming
audio.Amulticastserverdoesnothavetoestablishaseparateconnectionwitheachclient.It
merelybroadcastsitsservicetothenetwork,andanyhoststhatwanttoreceivethemulticast
registerwiththeirlocalmulticastswitch/router.Althoughthisapproachreducesthenetwork
overheadrequiredbyamulticastserver,thebroadcasttrafficmustbecarefullyprunedatevery
multicastswitch/routeritpassesthroughtoensurethattrafficisonlypassedtothehoststhat
subscribedtothisservice.
TheEnterasysMatrixSeriesswitchdeviceusesIGMP(InternetGroupManagementProtocol)to
queryforanyattachedhostswhowanttoreceiveaspecificmulticastservice.Thedevicelooksup
theIPMulticastGroupusedforthisserviceandaddsanyportthatreceivedasimilarrequestto
thatgroup.Itthenpropagatestheservicerequestontoanyneighboringmulticastswitch/routerto
ensurethatitwillcontinuetoreceivethemulticastservice.

Enabling / Disabling IGMP

Purpose
TodisplayIGMPinformationandtoenableordisableIGMPsnoopingonthedevice.
Commands

show igmp enable

UsethiscommandtodisplaythestatusofIGMPononeormoreVLAN(s).
Syntax
show igmp enable vlan-list
Parameters
Defaults
None.
For information about... Refer to page...
show igmp enable 9-2
set igmp enable 9-3
set igmp disable 9-3
vlanlistSpecifiestheVLAN(s)forwhichtodisplayIGMPstatus.