Chapter 23 DHCP
GS-2024 User’s Guide
168
Figure 88   IP Application > DHCP Status 
The following table describes the labels in this screen. 
23.3  DHCP Relay 
Configure DHCP relay on the Switch if the DHCP clients and the DHCP server are not in the 
same broadcast domain. During the initial IP address leasing, the Switch helps to relay 
network information (such as the IP address and subnet mask) between a DHCP client and a 
DHCP server. Once the DHCP client obtains an IP address and can connect to the network, 
network information renewal is done between the DHCP client and the DHCP server without 
the help of the Switch.
The Switch can be configured as a global DHCP relay. This means that the Switch forwards all 
DHCP requests from all domains to the same DHCP server. You can also configure the Switch 
to relay DHCP information based on the VLAN membership of the DHCP clients.
23.3.1  DHCP Relay Agent Information 
The Switch can add information about the source of client DHCP requests that it relays to a 
DHCP server by adding Relay Agent Information. This helps provide authentication about 
the source of the requests. The DHCP server can then provide an IP address based on this 
information. Please refer to RFC 3046 for more details. 
The DHCP Relay Agent Information feature adds an Agent Information field to the Option 
82 field. The Option 82 field is in the DHCP headers of client DHCP request frames that the 
Switch relays to a DHCP server.
Relay Agent Information can include the System Name of the Switch if you select this 
option. You can change the System Name in Basic Settings > General Setup. 
The following describes the DHCP relay information that the Switch sends to the DHCP 
server:
Table 57   IP Application > DHCP Status
LABEL DESCRIPTION
Relay Status This section displays configuration settings related to the Switch’s DHCP relay 
mode. 
Relay Mode This field displays:
• None - if the Switch is not configured as a DHCP relay agent.
• Global - if the Switch is configured as a DHCP relay agent only.
• VLAN - followed by a VLAN ID if it is configured as a relay agent for specific 
VLAN(s).
Table 58   Relay Agent Information
FIELD LABELS DESCRIPTION
Slot ID (1 byte) This value is always 0 for stand-alone switches.
Port ID (1 byte) This is the port that the DHCP client is connected to.