Build DHCP on CentOS 5.3

First day at new office, our DNS and DHCP server was down, IP address for user is between 192.168.1.100 - 192.168.1.255.

In my chase DNS and DHCP server installed in one machine using FreeBSD for internet gateway is in different and has ip 192.168.1.1 and has DMZ with range IP 192.168.1.2-192.168.1.99,  IP for DNS and DHCP  is 192.168.1.10.

To install dhcp in CentOS type :



# yum install dhcp

after install process finish, now let's configure dhcp.conf file in /etc/dhcpd.conf

first copy dhcp configuration file;

# cp /etc/dhcpd.conf.sample /etc/dhcpd.conf

then edit

# vi /etc/dhcpd.conf

ddns-update-style interim;
ignore client-updates;

subnet 192.168.1.0 netmask 255.255.255.0 {

# --- default gateway
option routers                     192.168.1.1; # ip address your local internet gateway
option subnet-mask          255.255.255.0;

option nis-domain             "cyberthug.com";
option domain-name        "cyberthug.com";
option domain-name-servers    202.73.99.44,61.247.0.4; #input your ISP DNS Server

option time-offset              -18000;    # Eastern Standard Time
# option ntp-servers        192.168.1.1;
option netbios-name-servers    192.168.1.10;
# --- Selects point-to-point node (default is hybrid). Don't change this unless
# -- you understand Netbios very well
#    option netbios-node-type 2;

range dynamic-bootp 192.168.1.100 192.168.1.255;
default-lease-time 21600;
max-lease-time 43200;

# we want the nameserver to appear at a fixed address

host pc01 {
hardware ethernet 00:1E:EC:01:E2:DC;
fixed-address 192.168.1.125;
}
host laptop01 {
hardware ethernet 00:1A:92:34:F9:19;
fixed-address 192.168.1.215;
}
}

Save after you edit.

Then restart dhcp using

# /etc/init.d/dhcpd restart