ZyXEL Communications GS2220 Series - Dhcp; Dhc P; DHCP Overview; What You Can Do

Chapter 44 DHCP
GS2220 Series User’s Guide
370
C HAPTER 44
DHCP
44.1 DHC P O ve rvie w
This chapter shows you how to configure the DHCP feature.
DHCP (Dynamic Host Configuration Protocol RFC 2131 and RFC 2132) allows individual computers to
obtain TCP/IP configuration at start-up from a server. If you configure the Switch as a DHCP relay agent,
then the Switch forwards DHCP requests to DHCP server on your network. If you do not configure the
Switch as a DHCP relay agent then you must have a DHCP server in the broadcast domain of the client
computers or else the client computers must be configured manually.
44.1.1 Wha t You C a n Do
• Use the DHC Pv4 Sta tus screen (
Section 44.3 on page 371) to display the relay mode.
• Use the DHC Pv4 O ptio n 82 Pro file screen (
Section 44.4.2 on page 373) to create DHCPv4 option 82
profiles.
• Use the DHC Pv4 G lo ba l Re la y screen (Section 44.4.3 on page 374) to configure global DHCPv4 relay.
• Use the DHC Pv4 G lo ba l Re la y Po rt screen (
Section 44.4.4 on page 375) to apply a different DHCP
option 82 profile to certain ports on the Switch.
• Use the VLAN Se tting screen (Section 44.4.6 on page 377) to configure your DHCPv4 settings based on
the VLAN domain of the DHCPv4 clients.
• Use the DHC Pv4 VLAN Po rt screen (Section 44.4.7 on page 378) to apply a different DHCP option 82
profile to certain ports in a VLAN.
• Use the DHC Pv6 Re la y screen (Section 44.5 on page 380) to enable and configure DHCPv6 relay.
• Use the DHCP Se rve r G ua rd screen (
Section 44.6 on page 382) to specify whether ports are trusted or
untrusted ports for DHCP packets.
44.1.2 Wha t You Ne e d to Kno w
Read on for concepts on DHCP that can help you configure the screens in this chapter.
DHC P Mo de s
If there is already a DHCP server on your network, then you can configure the Switch as a DHCP relay
agent. When the Switch receives a request from a computer on your network, it contacts the DHCP
server for the necessary IP information, and then relays the assigned information back to the computer.