1. Run:
system-view
The system view is displayed.
2. Run:
ip vpn-instance vpn-instance-name
The VPN instance view is displayed.
3. Run:
multicast forwarding-table downstream-limit limit
The maximum number of downstream nodes of a forwarding entry in the multicast
forwarding table is configured.
----End
9.6.4 Checking the Configuration
After control parameters for the multicast forwarding table are configured, you can check
information about the multicast routing table to ensure normal running of the multicast network.
Procedure
l Run the display multicast [ vpn-instance vpn-instance-name | all-instance ] forwarding-
table [ group-address [ mask { group-mask | group-mask-length } ] | source-address
[ mask { source-mask | source-mask-length } ] | incoming-interface { interface-type
interface-number | register } | outgoing-interface { include | exclude | match } { interface-
type interface-number | register | none } | statistics ] 
*
 command to check the multicast
forwarding table.
----End
9.7 Maintaining the Multicast Policy
Maintaining IPv4 multicast routing management involves testing multicast routing, checking
the RPF path and multicast path, clearing multicast forwarding and routing entries, and
monitoring multicast routing and forwarding.
9.7.1 Testing Multicast Routing
When a fault occurs during multicast data transmission, you can run the ping command to check
the RPF path and multicast path.
Context
When data transmission is abnormal, you can ping related multicast addresses to check the
multicast routing.
Procedure
l Run the ping multicast [ -i interface-type interface-number | -c count | -h ttl-value | -m
time | -p pattern | -q | -s packet(s)ize | -t timeout | -tos tos-value | -v ] 
*
 host command in
any view to ping a reserved group address.
Quidway S7700 Smart Routing Switch
Configuration Guide - Multicast 9 IPv4 Multicast Routing Management
Issue 01 (2011-07-15) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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