200Step Command Remarks1. Enter system view. system-view N/A2. Enter interface view. interface interface-typeinterface-number N/A3. Enable IPv6 releasenotification. ipv6 dhcp relay release-agent By default, IPv6 releasenotification is disabled.Enabling client offline detectionThis feature enables the DHCPv6 relay agent to detect the status of ND entries. After an ND entryages out, the DHCPv6 relay agent considers the client offline and deletes the relay entry for the client.For more information about ND, see Layer 3—IP Services Configuration Guide.To enable client offline detection:Step Command Remarks1. Enter system view. system-view N/A2. Enter interface view. interface interface-typeinterface-number N/A3. Enable client offline detection. ipv6 dhcp client-detect By default, client offlinedetection is disabled.Configuring DHCPv6 flood attack protectionThe DHCPv6 flood attack protection enables the DHCPv6 relay agent to detect DHCPv6 floodattacks according to the DHCPv6 packet rate threshold on a per-MAC basis.When the DHCPv6 relay agent receives a DHCPv6 packet from a client (MAC address), it creates aDHCPv6 flood attack entry in check state. If the number of DHCPv6 packets from the same MACaddress reaches the upper limit in the detection duration, the relay agent determines that the client islaunching a DHCPv6 flood attack. The DHCPv6 flood attack entry changes to the restrain state, andthe DHCPv6 relay agent discards the DHCPv6 packets from that client. When the aging time of theentry is reached, the DHCPv6 relay agent deletes the entry. If a DHCPv6 packet from the MACaddress arrives later, the DHCPv6 relay agent will create a flood attack entry and count the numberof incoming DHCPv6 packets for that client again.To configure DHCPv6 flood attack protection:Step Command Remarks1. Enter system view. system-view N/A2. (Optional) Set the DHCPv6packet rate threshold forDHCPv6 flood attackdetection.ipv6 dhcp flood-protectionthreshold packet-numbermillisecondsBy default, the device allows amaximum of 6 DHCPv6 packetsper 5000 milliseconds from eachDHCPv6 client.3. (Optional) Set the DHCPv6flood attack entry aging time.ipv6 dhcp flood-protectionaging-time timeThe default setting is 300seconds.4. Enter interface view. interface interface-typeinterface-number N/A5. Enable DHCPv6 flood attackprotection.ipv6 dhcp flood-protectionenableBy default, DHCPv6 flood attackprotection is disabled.
