The 1721 makes a handy dhcp server in a pinch.  It is a little easier
and cheaper than building a dedicated linux box running dhcpd, but not
as versitile.  If it fits your needs, just drop this config in place. 
Be warned - this version does not have any ACLs to block inbound intrusion
attempts or unauthorized administration.  See one of the other 1721
tutorials for information on security.

!
service nagle
no service pad
service timestamps debug datetime msec localtime show-timezone
service timestamps log datetime msec localtime show-timezone
service password-encryption
!
hostname my.dhcp.hostname.generic.com
!
! Identify the boot image
boot system flash c1700-sy-mz.122-15.T5.bin
logging queue-limit 100
enable secret 5 enablepassword
!
username root privilege 15 password rootpassword
ip subnet-zero
!
!
ip name-server 192.168.1.1
no ip dhcp conflict logging
ip dhcp excluded-address 10.0.0.1 10.0.0.10
!
ip dhcp pool local
   network 10.0.0.0 255.255.255.0
   domain-name generic.com
   default-router 10.0.0.1
   dns-server 192.168.1.1

ip dhcp pool server1_hardcode 
   host 10.0.0.5 255.255.255.0
   client-identifier 0100.084b.18bf.4f

no ip bootp server
!
!
!
!
interface FastEthernet0
 ip address 10.0.0.3 255.255.255.0
 speed 10
 half-duplex
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.0.0.1
no ip http server
!
!
!
!
snmp-server community privatename RO
snmp-server enable traps snmp authentication linkdown linkup coldstart warmstart
snmp-server enable traps tty
snmp-server enable traps hsrp
snmp-server enable traps config
snmp-server enable traps entity
snmp-server enable traps frame-relay
snmp-server enable traps frame-relay subif
snmp-server enable traps syslog
snmp-server enable traps rtr
banner motd ^C
=============================================
 DHCP Server : my.dhcp.hostname.generic.com
=============================================^C
!
line con 0
 login local
line aux 0
 login local
line vty 0 4
 login local
line vty 5 15
 login local
!
!