User guide

OmniSwitch 6600 Family Network Configuration Guide April 2005 page 17-1
17 Configuring DHCP Relay
The User Datagram Protocol (UDP) is a connectionless transport protocol that runs on top of IP networks.
The DHCP Relay allows you to use nonroutable protocols (such as UDP) in a routing environment. UDP
is used for applications that do not require the establishment of a session and end-to-end error checking.
Email and file transfer are two applications that could use UDP. UDP offers a direct way to send and
receive datagrams over an IP network and is primarily used for broadcasting messages. This chapter
describes the DHCP Relay feature. This feature allows UDP broadcast packets to be forwarded across
VLANs that have IP routing enabled.
In This Chapter
This chapter describes the basic components of DHCP Relay and how to configure them. CLI commands
are used in the configuration examples. For more details about the syntax of commands, see the
OmniSwitch CLI Reference Guide.
Configuration procedures described in this chapter include:
• Quick steps for configuring DHCP Relay on page 17-3.
• Setting the IP address for Global DHCP on page 17-8.
• Identifying the VLAN for Per-VLAN DHCP on page 17-9.
• Enabling BOOTP/DHCP Relay on page 17-9.
• Setting the Forward Delay time on page 17-10.
• Setting the Maximum Hops value on page 17-10.
• Setting the Relay Forwarding Option to Standard, Per-VLAN, or AVLAN on page 17-10.
• Using automatic IP configuration to obtain an IP address for the switch on page 17-11.
• Configuring relay for generic UDP service ports on page 17-12.
For information about the IP protocol, see Chapter 13, “Configuring IP.”