60Configuring the DHCP relay agent to release an IPaddressConfigure the relay agent to release the IP address for a relay entry. The relay agent sends aDHCP-RELEASE message to the server and meanwhile deletes the relay entry. Upon receiving theDHCP-RELEASE message, the DHCP server releases the IP address.To configure the DHCP relay agent to release an IP address:Step Command Remarks1. Enter system view. system-view N/A2. Configure the DHCP relayagent to release an IPaddress.dhcp relay release ip client-ip[ vpn-instance vpn-instance-name ]This command can release only theIP addresses in the recorded relayentries.Configuring Option 82Follow these guidelines when you configure Option 82:• To support Option 82, you must perform related configuration on both the DHCP server and relayagent. For DHCP server Option 82 configuration, see "Enabling handling of Option 82."• The system name (sysname) if padded in sub-option 1 (node identifier) of Option 82 must notcontain spaces. Otherwise, the DHCP relay agent drops the message.To configure Option 82:Step Command Remarks1. Enter system view. system-view N/A2. Enter interface view. interface interface-typeinterface-number N/A3. Enable the relay agent to handleOption 82. dhcp relay information enable By default, handling ofOption 82 is disabled.4. (Optional.) Configure the strategyfor handling DHCP requests thatcontain Option 82.dhcp relay information strategy{ drop | keep | replace }By default, the handlingstrategy is replace.5. (Optional.) Configure the paddingcontent and code type for thecircuit ID sub-option.dhcp relay information circuit-id{ string circuit-id | { normal |verbose [ node-identifier { mac |sysname | user-definednode-identifier } ] } [ format { ascii |hex } ] }By default, the paddingformat for circuit IDsub-option is normal, and thecode type is hex.6. (Optional.) Configure the paddingcontent and code type for theremote ID sub-option.dhcp relay information remote-id{ normal [ format { ascii | hex } ] |string remote-id | sysname }By default, the paddingformat for the remote IDsub-option is normal, and thecode type is hex.
