Configuring DVMRP ip dvmrp
21-52 Routing Protocol Configuration
Configuring DVMRP
Purpose
ToenableandconfiguretheDistanceVectorMulticastRoutingProtocol(DVMRP)onaninterface.
DVMRProutesmulticasttrafficusingatechniqueknownasReversePathForwarding.Whena
routerreceivesapacket,itfloodsthepacketoutofallpathsexcepttheonethatleadsbacktothe
packet’ssource.Doing
soallowsadatastreamtoreachallVLANs(possiblymultipletimes).Ifa
routerisattachedtoasetofVLANsthatdonotwanttoreceivefromaparticularmulticastgroup,
theroutercansenda“prune”messagebackupthedistributiontreetostopsubsequentpackets
from
travelingwheretherearenomembers.DVMRPwillperiodicallyrefloodinordertoreach
anynewhoststhatwanttoreceivefromaparticulargroup.
Commands
ip dvmrp
UsethiscommandtoenableordisableDVMRPonaninterface.
Syntax
ip dvmrp
no ip dvmrp
Parameters
None.
Defaults
None.
Mode
Routercommand,Interfaceconfiguration:Matrix>Router(config‐if(Vlan1))#
Usage
IGMPmustbeenabledonallVLANsrunningDVMRP.Todothis,usethesetigmpenable
commandasdescribedin“setigmpenable”onpage 9‐3.ItisalsorecommendedthatIGMP
queryingbeenabledonallVLANsrunningDVMRP.Todothis,usethesetigmpquery‐enable
commandasdescribedin“setigmpquery‐enable”onpage 9‐6.
Note: IGMP must be enabled on all VLANs running DVMRP. To do this, use the set igmp enable
command as described in “set igmp enable” on page 9-3. It is also recommended that IGMP
querying be enabled on all VLANs running DVMRP. To do this, use the set igmp query-enable
command as described in “set igmp query-enable” on page 9-6.
For information about... Refer to page...
ip dvmrp 21-52
ip dvmrp metric 21-53
show ip dvmrp route 21-53