208The DHCPv6-REQUEST check feature enables the DHCPv6 snooping device to check everyreceived DHCPv6-RENEW, DHCPv6-DECLINE, or DHCPv6-RELEASE message against DHCPv6snooping entries.• If any criterion in an entry is matched, the device compares the entry with the messageinformation.{ If they are consistent, the device considers the message valid and forwards it to theDHCPv6 server.{ If they are different, the device considers the message forged and discards it.• If no matching entry is found, the device forwards the message to the DHCPv6 server.ProcedureTo enable DHCPv6-REQUEST check:Step Command Remarks1. Enter system view. system-view N/A2. Enter interface view. interface interface-typeinterface-number N/A3. EnableDHCPv6-REQUESTcheck.ipv6 dhcp snooping checkrequest-messageBy default, DHCPv6-REQUEST check isdisabled.Configuring a DHCPv6 packet blocking portPerform this task to configure a port as a DHCPv6 packet blocking port. The DHCPv6 packetblocking port drops all incoming DHCP requests.To configure a DHCPv6 packet blocking port:Step Command Remarks1. Enter system view. system-view N/A2. Enter interface view. interface interface-typeinterface-number N/A3. Configure the port to blockDHCPv6 requests. ipv6 dhcp snooping deny By default, the port does not blockDHCPv6 requests.Enabling DHCPv6 snooping loggingThe DHCPv6 snooping logging feature enables the DHCPv6 snooping device to generate DHCPv6snooping logs and send them to the information center. For information about the log destination andoutput rule configuration in the information center, see Network Management and MonitoringConfiguration Guide.As a best practice, disable this feature if the log generation affects the device performance.To enable DHCPv6 snooping logging:Step Command Remarks1. Enter system view. system-view N/A2. Enable DHCPv6 snoopinglogging. ipv6 dhcp snooping log enable By default, DHCPv6 snoopinglogging is disabled.
