ip multicast dvmrp routeDisplay

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ip multicast dvmrp routeDisplay 517

For CoreBuilder 9000: Applies to Layer 3 switching modules only.

Displays IP multicast route information that your system has learned from using the Distance-Vector Multicast Routing Protocol (DVMRP). The system uses this information to forward IP multicast traffic that it receives.

Valid Minimum Abbreviation

ip m d r

Fields in the IP Multicast DVMRP Route Display

Field

Description

 

 

Origin

IP address of the subnetwork that contains an IP multicast

 

source, followed by a forward slash and subnetwork

 

mask.

Gateway

IP address of the routing interface that lies upstream of

 

the local system on the path back towards an IP multicast

 

source. If the source subnetwork is connected directly to

 

your system, this field contains a dash (--).

Metric

Number of hops from your system back to the origin

 

subnetwork. This value is not the DVMRP interface or

 

tunnel metric, which are shown under Metric in other

 

displays.

 

Occasionally, instead of a numeric value, you may see NR,

 

meaning “network unreachable.” Your system may have

 

trouble computing the hop count because of factors such

 

as an upstream router being temporarily congested. This

 

condition is usually resolved in a short period of time.

Tmr

Amount of time (in seconds) since each entry was last

 

reset.

Parent

The interface that connects to the upstream router

 

(Gateway). Because DVMRP forms a loopless spanning

 

tree to reach all hosts for a given IP multicast group, your

 

system always chooses a single parent interface. Either an

 

I or a T precedes the index number. An I indicates that

 

the index is an interface index number. A T indicates that

 

the index is a tunnel index number.

Children

Interfaces that communicate with downstream routers or

 

local subnetworks. The system forwards incoming IP

 

multicast traffic through these interfaces. Either an I or a

 

T precedes each index number. An I precedes an

 

interface index number. A T precedes a tunnel index

 

number.

 

 

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3Com 3500 manual Fields in the IP Multicast Dvmrp Route Display