Asante Technologies 35516 Configuring Igmp, Modifying the Igmp Host-Query Message Interval

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IGMP

The Internet Group Management Protocol (IGMP) manages the multicast groups on a LAN. IP hosts use IGMP to report their group membership to directly connected multicast routers. Routers executing a multicast routing protocol maintain forwarding tables to forward multicast datagrams. Routers use the IGMP to learn whether members of a group are present on their directly attached sub-nets. Hosts join multicast groups by sending IGMP report messages.

IGMP uses group addresses, which are Class D IP addresses. The high-order four bits of a Class D address are 1110. Therefore, host group addresses can be in the range 224.0.0.0 to 239.255.255.255.

The address 224.0.0.0 will not be assigned to any group. The address 224.0.0.1 is assigned to all systems on a sub-net. The address 224.0.0.2 is assigned to all routers on a sub-net.

DVMRP

Distance Vector Multicast Routing Protocol (DVMRP) is a routing protocol that provides packet delivery to a group of hosts across an inter-network. DVMRP routers dynamically discover their neighbors by sending neighbor probe messages periodically to an IP multicast group address that is reserved for all DVMRP routers. These mechanisms allow the formation of shortest-path trees, which are used to forward packets to all group members from each network source of multicast traffic. Multicast packets are initially flooded down a source tree. If redundant paths are on the source tree, packets are not forwarded along those paths. Forwarding occurs until Prune messages are received on those links, which further constrain the broadcast of multicast packets.

DVMRP is designed as an interior gateway protocol (IGP) within a multicast domain.

5.5.1 Configuring IGMP

Use the following commands to configure IGMP.

Modifying the IGMP Host-Query Message Interval

Multicast routers send IGMP host-query messages to discover which multicast groups are present on attached networks. These messages are sent to the all-systems group address of 224.0.0.1 with a time-to- live (TTL) value of 1.

Multicast routers continue to periodically send host-query messages to refresh their knowledge of memberships present on their networks. If, after some number of queries, the router software discovers that no local hosts are members of a multicast group, the software stops forwarding onto the local network multicast packets from remote origins for that group and sends a prune message upstream toward the source.

Multicast routers elect designated router (DR) for the LAN (subnet). The DR is the router with the highest IP address. The DR is responsible for sending IGMP host-query messages to all hosts on the LAN. By default, the DR sends IGMP host-query messages every 60 seconds in order to keep the IGMP overhead on hosts and networks very low. To modify this interval, use the following command in interface configuration mode:

 

Command

Purpose

 

 

ip igmp query-interval <1-65535 seconds>

Configure the frequency at which the designated router

 

 

 

sends IGMP host-query messages.

 

 

 

 

 

 

 

 

 

Router(config-if-veth1)# ip igmp query-interval 200

 

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Contents IntraCore 35516 Series IntraCore 35516 Series Technical SupportTable of Contents Page Features IntroductionPackage Contents LEDsFront and Back Panel Descriptions GbicManagement and Configuration Console InterfaceSafety Overview Hardware Installation and SetupInstallation Overview Recommended Installation ToolsEnvironmental Requirements Installation into an Equipment RackPower Requirements Cooling and AirflowInstalling a Gbic Gigabit Interface ConvertersGbic Care and Handling Installing the Optional Emergency Power SupplyRemoving a Gbic System Information System up since 103443 Fri Feb 071 10/100/1000BaseT Ports Cabling Procedures Connecting PowerConnecting to the Network Connecting to a Console SetupGigabit Ethernet Ports Cabling Procedures User Access Verification Password Specifies an Unencrypted line password will follow Setting PasswordsUnencrypted cleartext line password Specifies a Hidden line password will followRouterconfig-if-veth1# Configuring an IP AddressSetting a Default IP Gateway Address Routerconfig# boot system flash bank1bank2 Restoring Factory DefaultsSystem Boot Parameters Access Each Command Mode Understanding the Command Line Interface CLIUser Top User Exec Mode Command Show ? PurposeCommand Purpose Privileged Top Privileged Exec ModeRouter enable Password Router# Command Exit end Ctrl-Z Purpose Global Configuration ModeCommand Purpose Router# configure terminal Interface Configuration Mode Router Configuration Mode Route-Map Configuration ModeAdvanced Features Supported within the Command Mode Command Help PurposeRouterconfig# routed rip Invalid input detected at marker Checking Command SyntaxRouterconfig# hostname ? Word This systems network name Routerconfig# route Ambiguous command. Routerconfig#Using Command-Line Editing Features and Shortcuts Using CLI Command HistoryUsing the No and Default Forms of Commands Routerconfig# router Command incomplete. Routerconfig#Router# confTab Router# configure Moving Around on the Command LineCompleting a Partial Command Name Keystrokes PurposeDeleting Entries Editing Command Lines that WrapRouter# co? configure copy Router# co Keystrokes Purpose Press the Delete or BackspaceTransposing Mistyped Characters Redisplaying the Current Command LineScrolling Down a Line or a Screen Controlling CapitalizationPassword Passwords and Privileges CommandsEnable Password Routerconfig-line# password AsanteService Password-Encryption Changing the Password Managing the System and Configuration FilesSetting the System Clock Managing the SystemTrace Packet Routes Enable the System LogDisplaying the Operating Configuration Test Connections with Ping TestsConfiguration to Nvram Managing Configuration FilesConfiguring from the Terminal Routerconfig# hostname newname Newnameconfig# endCopying Configuration Files to a Network Server Running-config Configuring Snmp and Spanning TreeConfiguring Snmp Support Startup-configRouterconfig# duplicate-ip detect Configuring Spanning Tree Protocol STPCreate or Modify Access Control for Snmp Community Disable the Snmp ProtocolMaximum Age Forward TimeHello Time PriorityPort Priority Routerconfig# mac-address-table aging-timeMAC Address Table Port Path CostAssign IP Addresses to Network Interfaces Configuring IPConfiguring IP Addressing Class Address or Range StatusCidr Prefix Class C Equivalent Host Addresses Command PurposeAssign Multiple IP Addresses to Network Interfaces Define a Static ARP Cache Establish Address ResolutionConfiguring IP Routing SecondaryConfiguring Static Routes Route Source Default DistanceAllow Unicast Updates for RIP Configuring RIPEnable RIP Neighbor ip-addressRedistribute Routing Information Command Purpose Route-map map-tagdeny permit sequenceSpecify a RIP Version Set Administrative Distance Set Metrics for Redistributed RoutesFiltering Routing Information Generate a Default RouteSuppress Routing Updates through an Interface Manage Authentication Keys Adjust TimersEnable or Disable Split-horizon Command Purpose Offset-list access-list-name in outConfiguring IP Multicast Routing Monitor and Maintain RIPPurpose Ip igmp query-interval 1-65535 seconds Configuring IgmpModifying the Igmp Host-Query Message Interval Changing the Igmp Version CommandConfiguring the Router as a Statically Connected Member SecondsConfiguring Dvmrp Nbr-timeout 35-8000 secondsDefault value 200 seconds Default value 180 secondsCommand Purpose Route-expire-time 20-4000 seconds Report-intervalUsing Access Lists Create a Standard Access ListCreate an Expanded Access List Destination address to match. e.gOperator equal to Creating an Access List with a NameApplying an Access List to an Interface Operator greater thenConfigure ABR Type Configuring OspfEnable Ospf Command Purpose Router ospf StepConfigure Ospf Network Type Configure CompatibilityConfigure Ospf Interface Parameters Configure Ospf Not So Stubby Area Nssa Configure Ospf for Non-broadcast NetworksConfigure Area Parameters Command Purpose Neighbor ip-address priority numberCreate Virtual Links Configure Route Summarization between Ospf AreasCommand Purpose Area area-idvirtual-link router-idhello Not-advertisedRefresh Timer Configuration Control Default MetricsConfigure Route Calculation Timers Redistribute Routes into OspfCommand Purpose Distance ospf external distance1 inter-area Change the Ospf Administrative DistancesPrevent Routes from being Advertised in Routing Updates Suppress Routes on an InterfaceRouter ip-address NameVrrp Configuration Virtual Router Redundancy Protocol VrrpMonitoring and Maintaining the Network Configuring Icmp Router Discovery Protocol IrdpEnable Irdp Processing Change Irdp ParametersShow ip prefix-list prefix-list-name Command Purpose Show arp interfaceShow access-lists access-list Show ip irdpVlan Configuration Creating or Modifying a VlanDeleting a Vlan Routerconfig# interface veth2 vlan Routerconfig-if-veth2#Routerconfig# no vlan Routerconfig# exit Router# show vlan Trunk Ieee 802.1Q Static AccessVlan Port Membership Modes Trunk allowed vlan add all except Command Purpose Routerconfig# vlan dot1q tag native3 Dot1q Tunnel Mode dot1q-tunnel Appendix A. Basic Troubleshooting Problem Possible SolutionsTechnical Support and Warranty Appendix B. SpecificationsPhysical Characteristics Standards ComplianceIntraCare Warranty Statement Appendix C. FCC Compliance and Warranty StatementsFCC Compliance Statement Important Safety Instructions Page Pin Number Signal Name Appendix D. Console Port Pin OutsAppendix E. Online Warranty Registration
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