This document provides instructions for configuring IP addresses, hostnames, DHCP server, and DNS server on a Debian Lenny server. It describes editing configuration files such as interfaces, hostname, and dhcpd.conf to set the IP address, netmask, gateway and hostname. It also explains installing the dhcp3-server and bind9 packages and editing files such as dhcpd.conf and named.conf to configure the DHCP and DNS servers, respectively. Commands shown include ifconfig, hostname, service networking commands, and apt-get install.