D-Link DES-1228/ME User Manual page 47

The Implementation of DHCP Information Option 82 in the DES-1228/ME switches
The config dhcp_relay option_82 command configures the DHCP relay agent information option 82 setting of the switch. The
formats for the circuit ID sub-option and the remote ID sub-option are as follows:
NOTE: For the circuit ID sub-option of a standalone switch, the module field is always zero.
1. Sub-option type
2. Length
3. Circuit ID type
4. Length
5. VLAN : the incoming VLAN ID of DHCP client packet.
6. Module : For a standalone switch, the Module is always 0; For a stackable switch, the Module is the Unit ID.
7. Port : The incoming port number of DHCP client packet, port number starts from 1.
1. Sub-option type
2. Length
3. Remote ID type
4. Length
5. MAC address: The Switch's system MAC address.
1. Sub-option type
2. Length: the string length of the Remote ID suboption
3. Remote ID type
4. Length: the string length of the user-defined string
5. User-defined string
DES-1228/ME Layer 2 Fast Ethernet Managed Switch
Circuit ID sub-option format:
Remote ID sub-option format 1:
Remote ID sub-option format 2:
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