(Optional) Configuring the Function of Checking the Retransmission Rate of DAD NS Packets

Context

If an untrusted interface on a device receives a DAD NS packet, the interface forwards the packet for the duplicate address detection and bogus user check. To avoid the situation that the remote interface cannot receive packets forwarded by the local device because of packet loss when the ND snooping binding entry is not established, configure the untrusted interface on the local device to forward a DAD NS packet after receiving it. By default, a device does not control the retransmission rate of DAD NS packets. When excessive packets are received, packet retransmission may affect normal operation of network services. To solve this problem, you can configure the function of checking the retransmission rate of DAD NS packets. After this function is configured, the device limits the retransmission rate of DAD NS packets. If the number of DAD NS packets retransmitted per second exceeds the specified value, the device directly discards excessive packets instead of forwarding these packets.

Procedure

Configure the function of checking the retransmission rate of DAD NS packets in the system view.
1. Run system-view
  The system view is displayed.
2. Run nd snooping check dad-ns retransmit-rate enable
  The function of checking the retransmission rate of DAD NS packets is enabled.
  
  By default, the function of checking the retransmission rate of DAD NS packets is disabled.
3. Run nd snooping check dad-ns retransmit-rate rate rate-value
  The maximum retransmission rate of DAD NS packets is configured.
  
  By default, the maximum retransmission rate of DAD NS packets is 50 packets per second.
Configure the function of checking the retransmission rate of DAD NS packets in the VLAN view.
1. Run system-view
  The system view is displayed.
2. Run vlan vlan-id
  The VLAN view is displayed.
3. Run nd snooping check dad-ns retransmit-rate enable
  The function of checking the retransmission rate of DAD NS packets is enabled.
  
  By default, the function of checking the retransmission rate of DAD NS packets is disabled.
4. Run nd snooping check dad-ns retransmit-rate rate rate-value
  The maximum retransmission rate of DAD NS packets is configured.
  
  By default, the maximum retransmission rate of DAD NS packets is 50 packets per second.
Configure the function of checking the retransmission rate of DAD NS packets in the interface view.
1. Run system-view
  The system view is displayed.
2. Run interface interface-type interface-number
  The interface view is displayed.
3. Run nd snooping check dad-ns retransmit-rate enable
  The function of checking the retransmission rate of DAD NS packets is enabled.
  
  By default, the function of checking the retransmission rate of DAD NS packets is disabled.
4. Run nd snooping check dad-ns retransmit-rate rate rate-value
  The maximum retransmission rate of DAD NS packets is configured.
  
  By default, the maximum retransmission rate of DAD NS packets is 50 packets per second.