ES-3124 User’s Guide
Chapter 23 DHCP Relay 183
CHAPTER 23
DHCP Relay
This chapter shows you how to set up DHCP relay.
23.1 DHCP Relay Overview
DHCP (Dynamic Host Configuration Protocol, RFC 2131 and RFC 2132) allows individual
clients to obtain TCP/IP configuration at start-up from a DHCP server. You can configure the
switch to relay client DHCP requests to a DHCP server and the server's responses back to the
clients.
23.1.1 DHCP Relay Agent Information
The switch can add information to client DHCP requests that it relays to a DHCP server. This
helps provide authentication about the source of the requests. You can also specify additional
information for the switch to add to the client DHCP requests that it relays to the DHCP
server. Please refer to RFC 3046 for more details.
The DHCP relay agent information feature adds an Agent Information field to the option 82
field of the DHCP headers of client TCP/IP configuration request frames that the switch relays
to a DHCP server. The following lists the DHCP relay agent option 82 information that the
switch sends to the DHCP server:
• Slot ID (1 byte)
• Port ID (1 byte)
• VLAN ID (2 bytes)
• System name (up to 32 bytes, this is optional).
23.2 DHCP Relay Configuration
To configure DHCP relay information and specify the DHCP server(s), click Advanced
Application and DHCP Relay to display the screen as shown next.
