3Com 10002211 manual Administering IP, Multicast, Interfaces

Administering IP Multicast Interfaces A-3

			When you select the IGMP option, the interface prompts you to enable or
			disable IGMP snooping mode and IGMP query mode. Both are enabled by
			default. Under most conditions, IGMP snooping mode and IGMP query
			mode should remain enabled.
Top-Level Menu			To enable or disable IGMP, from the top level of the Administration Console,
system
ethernet	interface		enter:
fddi	route	dvrmp
tokenring	arp	➧igmp	ip multicast igmp
bridge	➧multicast	interface
➧ip	udpHelper	tunnel	1 Enter the slot of the switching module for which you want to enable IGMP.
ipx	routing	routeDisplay
appletalk	icmpRouterDis	cacheDisplayovery	Select IP stack(s) by slot (2,3,7,9-12all) [12]:
snmp	rip
analyzer	ping
script	statistics		2 The interface prompts you to enable or disable IGMP query mode and IGMP
logout
			snooping mode. If an IP interface has been defined on an EFSM or a TMM
			module in the CoreBuilder system, IGMP snooping mode is enabled by
			default.
			Slots 9-12 - Enter IGMP snooping mode (disabled, enabled)
			[enabled]: enabled
Administering IP			The IP multicast interface selections allow you to enable and disable
Multicast			multicast characteristics on previously defined IP interfaces. A multicast
Interfaces			interface has three characteristics, explained next.

DVMRP Metric Value

The DVMRP metric value determines the cost of a multicast interface. The higher the cost, the less likely it is that the packets will be routed over the interface. The default value is 1.

Time To Live (TTL) Threshold

The TTL threshold determines whether the interface will forward multicast packets to other switches and routers in the subnetwork. If the interface TTL is greater than the packet TTL, then the interface does not forward the packet. The default value is 1, which means that the interface will forward all packets.