H3C Technologies H3C S10500 Series Switches - Manual (Page 311)

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# Display the information about FF1E::101 in the IPv6 multicast forwarding table on Switch A.
[SwitchA] display multicast ipv6 forwarding-table ff1e::101
IPv6 Multicast Forwarding Table
Total 1 entry
Total 1 entry matched
00001. (1::1, FF1E::101)
MID: 0, Flags: 0x0:0
Uptime: 00:08:32, Timeout in: 00:03:26
Incoming interface: Vlan-interface101
List of 1 outgoing interfaces:
1: Vlan-interface104
Matched 19648 packets(20512512 bytes), Wrong If 0 packets
Forwarded 19648 packets(20512512 bytes)
The output shows that Switch A maintains a multicast forwarding entry for multicast packets from Source
1 to FF1E::101. No forwarding entry exists for packets from Source 2 to FF1E::101, which indicates that
IPv6 multicast packets from Source 2 are blocked.
Troubleshooting MLD snooping
Layer 2 multicast forwarding cannot function
Symptom
Layer 2 multicast forwarding cannot function.
Analysis
MLD snooping is not enabled.
Solution
1. Use the display current-configuration command to display the running status of MLD snooping.
2. If MLD snooping is not enabled, use the mld-snooping command to enable MLD snooping globally,
and then use mld-snooping enable command to enable MLD snooping in VLAN view.
3. If MLD snooping is disabled only for the corresponding VLAN, use the mld-snooping enable
command in VLAN view to enable MLD snooping in the corresponding VLAN.
Configured IPv6 multicast group policy fails to take effect
Symptom
Although an IPv6 multicast group policy has been configured to allow hosts to join specific IPv6 multicast
groups, the hosts can still receive IPv6 multicast data addressed to other groups.
Analysis
• The IPv6 ACL rule is incorrectly configured.
• The IPv6 multicast group policy is not correctly applied.