Configuring Dhcp-Based Autoconfiguration; Understanding Dhcp-Based Autoconfiguration - Cisco 4500M Software Manual

Configuring DHCP-Based Autoconfiguration

Table 3-1
Feature
Passwords
Switch prompt
Interfaces
Configuring DHCP-Based Autoconfiguration
These sections describe how to configure DHCP-based autoconfiguration.
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If your DHCP server is a Cisco device, or if you are configuring the switch as a DHCP server, refer to
the "IP Addressing and Services" section in the Cisco IOS IP and IP Routing Configuration Guide for
Cisco IOS Release 12.1 for additional information about configuring DHCP.

Understanding DHCP-Based Autoconfiguration

Note Starting with Release 12.2(20)EW, you can enable DHCP AutoConfiguration by issuing the write erase
command. This command clears the startup-config in NVRAM. In images prior to Release 12.2(20)EW,
this command will not enable autoconfiguration.
DHCP provides configuration information to Internet hosts and internetworking devices. This protocol
consists of two components: one component for delivering configuration parameters from a DHCP
server to a device and another component that is a mechanism for allocating network addresses to
devices. DHCP is built on a client-server model, in which designated DHCP servers allocate network
addresses and deliver configuration parameters to dynamically configured devices. The switch can act
as both a DHCP client and a DHCP server.
With DHCP-based autoconfiguration, no DHCP client-side configuration is needed on your switch
because your switch (the DHCP client) is automatically configured at startup with IP address
information and a configuration file. However, you need to configure the DHCP server or the DHCP
server feature on your switch for various lease options associated with IP addresses. If you are using
DHCP to relay the configuration file location on the network, you might also need to configure a Trivial
File Transfer Protocol (TFTP) server and a Domain Name System (DNS) server.
DHCP-based autoconfiguration replaces the BOOTP client functionality on your switch.
Software Configuration Guide—Release 12.2(25)EW
3-2
Default Switch Configuration (continued)
Understanding DHCP-Based Autoconfiguration, page 3-2
DHCP Client Request Process, page 3-3
Configuring the DHCP Server, page 3-3
Configuring the TFTP Server, page 3-4
Configuring the DNS Server, page 3-5
Configuring the Relay Device, page 3-5
Obtaining Configuration Files, page 3-6
Example Configuration, page 3-7
Chapter 3
Default Settings
No passwords are configured for normal mode or enable mode
(press the Return key)
Switch>
Enabled, with speed and flow control autonegotiated, and without
IP addresses
Configuring the Switch for the First Time
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