System information

xStack

DGS-3200 Series Layer 2 Gigabit Ethernet Managed Switch

The Implementation of DHCP Relay Agent Information Option 82

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.

Circuit ID sub-option format:

1. 2. 3. 4. 5. 6. 7.

1 6 0 4 VLAN Module Port

1 byte 1 byte 1 byte 1 byte 2 bytes 1 byte 1 byte

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 the DHCP client packet, the port number starts from 1.

Remote ID sub-option format:

1. 2. 3. 4. 5.

2 8 0 6 MAC address

1 byte 1 byte 1 byte 1 byte 6 bytes

1. Sub-option type

2. Length

3. Remote ID type

4. Length

5. MAC address: The Switch’s system MAC address.

Figure 2 - 19. Circuit ID and Remote ID Sub-option Format