HOWTO DHCP SERVER RHEL 5

DHCP

Dynamic Host Configuration Protocol
Author Cristhian Nunez
Date 2007-06-05

Overview

DHCP is a set of rules used by communications devices such as a computer, router or network adapter to allow the device to request and obtain an IP address from a server which has a list of addresses available for assignment.

DHCP is a protocol used by networked computers (clients) to obtain IP addresses and other parameters such as the default gateway, subnet mask, and IP addresses of DNS servers from a DHCP server. It facilitates access to a network because these settings would otherwise have to be made manually for the client to participate in the network.

The DHCP server ensures that all IP addresses are unique, e.g., no IP address is assigned to a second client while the first client's assignment is valid (its lease has not expired). Thus IP address pool management is done by the server and not by a human network administrator.

Requirenments
- dhcp-3.0.5-3.el5.rpm

Implementation

-> Install the rpm file
rpm -ivh dhcp-3.0.5-3.el5.rpm
-> Create the /etc/dhcpd.conf
-> Add the following lines
addns-domainname "mydomain.local";
ddns-update-style interim;
option domain-name-servers 10.1.0.15,10.1.0.12; #Dns for the clients
default-lease-time 18000; #assigns time in seconds to a client with ip address
max-lease-time 25200; #Max lease time in seconds
option routers 10.0.0.1; # Assigns the default gateway to a client
option subnet-mask 255.0.0.0;
option domain-name "onemax.local";
option ntp-servers 10.1.0.13; # NTP Server
subnet 10.0.0.0 netmask 255.0.0.0 { # IP Range to offer the clients
range 10.0.0.20 10.0.0.199;
}

-> After save the file, start the service.
/etc/init.d/dhcpd start
-> Start Dhcp at every linux restart
chkconfig –level 345 dhcpd on