H3C Technologies H3C S3100V2 Series Switches - Manual (Page 102)

94
Host port(s):total 1 port(s).
Eth1/0/3
The output shows that Ethernet 1/0/3 on Switch B has joined FF1E::101 but not FF1E::102.
Assume that Source 2 starts sending multicast traffic to FF1E::101. Use the display multicast ipv6
forwarding-table to display the IPv6 multicast forwarding table information.
# 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. It indicates that IPv6
multicast packets from Source 2 are blocked.
Troubleshooting MLD snooping
Switch fails in layer 2 multicast forwarding
Symptom
A switch fails to implement Layer 2 multicast forwarding.
Analysis
MLD snooping is not enabled.
Solution
1. Enter the display current-configuration command to view 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, just 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.