3-5
Catalyst 2960 Switch SoftwareConfiguration Guide
78-16881-01
Chapter3 Assigning the Switch IP Address and Default Gateway
Assigning Switch Information
Configuring DHCP-Based Autoconfiguration
These sections contain this configuration information:
DHCP Server Configuration Guidelines, page 3-5
Configuring the TFTP Server, page 3-5
Configuring the DNS, page 3-6
Configuring the Relay Device, page 3-6
Obtaining Configuration Files, page 3-7
Example Configuration, page 3-8
If your DHCP server is a Cisco device, see the “Configuring DHCP” section of the “IP Addressing and
Services” section of the Cisco IOS IP Configuration Guide, Release 12.2 for additional information
about configuring DHCP.

DHCP Server Configuration Guidelines

Follow these guidelines if you are configuring a device as a DHCP server:
You should configure the DHCP server with reserved leases that are bound to each switch by the switch
hardware address.
If you want the switch to receive IP address information, you must configure the DHCP server with these
lease options:
IP address of the client (required)
Subnet mask of the client (required)
DNS server IP address (optional)
Router IP address (default gateway address to be used by the switch) ( required)
If you want the switch to receive the configuration file from a TFTP server, you must configure the
DHCP server with these lease options:
TFTP server name (required)
Boot filename (the name of the configuration file that the client needs) (recommended)
Hostname (optional)
Depending on the settings of the DHCP server, the switch can receive IP address information, the
configuration file, or both.
If you do not configure the DHCP server with the lease options described previously, it replies to client
requests with only those parameters that are configured. If the IP address and the subnet mask are not in
the reply, the switch is not configured. If the router IP address or the TFT P server name are not found,
the switch might send broadcast, instead of unicast, TFTP requests. Unavailability of other lease options
does not affect autoconfiguration.

Configuring the TFTP Server

Based on the DHCP server configuration, the switch attempts to download one or more configuration
files from the TFTP server. If you configured the DHCP server to respond to the switch with all the
options required for IP connectivity to the TFTP server, and if you configured the DHCP server with a
TFTP server name, address, and configuration filename, the switch attempts to download the specified
configuration file from the specified TFTP server.