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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
Chapter 3 Assigning the Switch IP Address and Default Gateway Assigning Switch Information
TFTP Server Configuration (on UNIX)
The TFTP server base directory is set to /tftpserver/work/. This directory contains the network-confg file
used in the two-file read method. This file contains the hostname to be assigned to the switch based on
its IP address. The base directory also contains a configuration file for each switch (switcha-confg,
switchb-confg, and so forth) as shown in this display:
prompt> cd /tftpserver/work/
prompt> ls
network-confg
switcha-confg
switchb-confg
switchc-confg
switchd-confg
prompt> cat network-confg
ip host switcha 10.0.0.21
ip host switchb 10.0.0.22
ip host switchc 10.0.0.23
ip host switchd 10.0.0.24
DHCP Client Configuration
No configuration file is present on Switch A through Switch D.
Configuration Explanation
In Figure 3-3, Switch A reads its configuration file as follows:
• It obtains its IP address 10.0.0.21 from the DHCP server.
• If no configuration filename is given in the DHCP server reply, Switch A reads the network-confg
file from the base directory of the TFTP server.
• It adds the contents of the network-confg file to its host table.
• It reads its host table by indexing its IP address 10.0.0.21 to its hostname (switcha).
• It reads the configuration file that corresponds to its hostname; for example, it reads switch1-confg
from the TFTP server.
Switches B through D retrieve their configuration files and IP addresses in the same way.
Configuring the DHCP Auto Configuration and Image Update Features
Using DHCP to download a new image and a new configuration to a switch requires that you configure
at least two switches: One switch acts as a DHCP and TFTP server. The client switch is configured to
download either a new configuration file or a new configuration file and a new image file.

Configuring DHCP Autoconfiguration (Only Configuration File)

Beginning in privileged EXEC mode, follow these steps to configure DHCP autoconfiguration of the
TFTP and DHCP settings on a new switch to download a new configuration file.
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 ip dhcp poolname Create a name for the DHCP Server address pool, and enter DHCP
pool configuration mode.
Step 3 bootfile filename Specify the name of the configuration file that is used as a boot image.