The ipv6 nd ns multicast-enable command enables a sub-interface for Dot1q VLAN tag termination to send NS multicast packets.
The undo ipv6 nd ns multicast-enable command disables a sub-interface for Dot1q VLAN tag termination from sending NS multicast packets.
By default, a sub-interface for Dot1q VLAN tag termination is disabled from sending NS multicast packets.
Usage Scenario
A sub-interface for Dot1q VLAN tag termination on a route device can send NS multicast packets to actively learn ND entries or respond to NS packets to passively learn ND entries.
When a sub-interface for Dot1q VLAN tag termination needs to send multicast NS packets to actively learn ND entries but there is no corresponding ND entries, you need to run the ipv6 nd ns multicast-enable command to enable a sub-interface for Dot1q VLAN tag termination to send NS multicast packets.
Prerequisites
Do as follows before running the ipv6 nd ns multicast-enable command:
Run the ipv6 enable command in the sub-interface view to enable IPv6 on an interface.
Configuration Impact
The system discards NS multicast packets when the ipv6 nd ns multicast-enable command is not run on the sub-interface for VLAN tag termination.
The system tags NS multicast packets and forwards them through the sub-interface for VLAN tag termination when the ipv6 nd ns multicast-enable command is run on the sub-interface for VLAN tag termination.
Sending multicast NS packets consumes CPU resources. Therefore, do not enable a sub-interface for Dot1q VLAN tag termination to send multicast NS packets when the CPU performance of the system is rather low.