3Com CoreBuilder 2500, User Manual

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Administering IP Multicast Interfaces 11-3
Administering IP
Multicast Interfaces
With the IP multicast interface selections, you can enable and disable
multicast characteristics on previously defined IP interfaces.
Multicast Interface
Characteristics
A multicast interface has three characteristics:
■
DVMRP Metric Value — Determines the cost of a multicast interface.
Use a higher cost to decrease the likelihood that multicast packets will
be routed over the interface. The default value is
1 .
■
Time To Live (TTL) Threshold — Determines whether the interface
forwards multicast packets to other switches and routers in the
subnetwork. If you do not want the interface to forward packets, use
an interface TTL greater than the packet TTL. If you want the interface
to forward all packets, use the default value of
1 .
■
Rate Limit — Determines how fast multicast traffic can travel over
the interface in packets per second. If multicast traffic exceeds the rate
limit, the system drops packets to maintain the set rate. If you want no
rate limit, use the default value of
0. If you want to reduce traffic over
the interface, use a low rate limit.
Displaying Multicast
Interfaces
To display a multicast interface:
1 From the top level of the Administration Console, enter:
ip multicast interface display
2 Enter the index numbers of the interfaces to display.
This example shows a multicast interface configuration:
Top-Level Menu
system
ethernet
fddi
atm
bridge
➧
ip
ipx
appletalk
snmp
analyzer
script
logout
interface
route
arp
atmArpServer
➧
multicast
udpHelper
icmpRouterDiscovery
rip
ping
statistics
dvmrp
igmp
➧
interface
tunnel
routeDisplay
cacheDisplay
➧
display
enable
disable
Index Local Address Metric Threshold RateLimit State
1 158.101.112.32 1 1 0 querier leaf
pkts in:0 pkts out:0
DVRMP is disabled, IGMP snooping is enabled