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2.
If MLD snooping is not enabled, enter system view and use the
mld-snooping
command to
enable MLD snooping globally. Then, enter VLAN view and use the
mld-snooping enable
and
pim-snooping ipv6 enable
commands to enable MLD snooping and IPv6 PIM snooping for
the VLAN.
3.
If IPv6 PIM snooping is not enabled, enter VLAN view and use the
pim-snooping ipv6 enable
command to enable IPv6 PIM snooping for the VLAN.
Some downstream IPv6 PIM-capable routers cannot receive
multicast data
Symptom
In a network with fragmented join/prune messages, some downstream IPv6 PIM-capable routers
cannot receive multicast data.
Analysis
IPv6 PIM snooping cannot reassemble messages, and it cannot maintain the status of downstream
routers that the join/prune message fragments carry. To ensure the normal operation of the system,
IPv6 PIM snooping must broadcast join/prune message fragments in the VLAN.
However, if the VLAN instance has an IPv6 PIM-capable router that has the join suppression function
enabled, the broadcast join/prune message fragments might suppress the join messages of other
IPv6 PIM-capable routers in the VLAN. As a result, some IPv6 PIM-capable routers cannot receive
the multicast data addressed to a specific multicast group because their join messages are
suppressed. To solve this problem, disable the join suppression function on all IPv6 PIM-capable
routers that connect to the IPv6 PIM snooping-capable switch in the VLAN.
Solution
1.
Use the
pim ipv6 hello-option neighbor-tracking
command to enable the neighbor tracking
function on the interfaces of IPv6 PIM-capable routers that connect to the IPv6 PIM
snooping-capable switch.
2.
If an IPv6 PIM-capable router cannot be enabled with the neighbor tracking function, be sure to
disable IPv6 PIM snooping on the switch.
