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

subnet 172.16.0.0 netmask 255.240.0.0 {
# default gateway
option routers 172.31.255.254;

option subnet-mask 255.240.0.0;
option nis-domain "nis-domain";
option domain-name "domain.name";
option domain-name-servers ns1.domain.name, ns2.domain.name;
# ntp server, nếu có
# option ntp-servers 172.16.0.2;

# dành 100 địa chỉ IP cho DHCP client
range dynamic-bootp 172.30.255.1 172.30.255.100;
default-lease-time 7200;
max-lease-time 18000;

# những máy luôn nhận IP cố định
host duyendang {
hardware ethernet 08:00:20xxx;
fixed-address 172.31.0.1;
}
host xinhxinh {
hardware ethernet 00:03:93xxx;
fixed-address 172.31.0.2;
option host-name "xinhxinh";
}
} 

#!/bin/sh
#
# dhcpd This script takes care of starting and stopping
# dhcpd.
#
# chkconfig: - 65 35
# description: dhcpd provide access to Dynamic Host Control Protocol.

# Source function library.
. /etc/rc.d/init.d/functions

# Source networking configuration.
. /etc/sysconfig/network
. /etc/sysconfig/dhcpd

# Check that networking is up.
[ ${NETWORKING} = "no" ] && exit 0

[ -f /usr/sbin/dhcpd ] || exit 0
[ -f /etc/dhcpd.conf ] || exit 0
[ -f /var/lib/dhcp/dhcpd.leases ] || touch /var/lib/dhcp/dhcpd.leases

RETVAL=0
prog="dhcpd"

configtest()
{
local retval TEMP=/tmp/dhcpd$$.err

/usr/sbin/dhcpd -t 2>$TEMP
retval=$?
if [ $retval -ne 0 ]
then
cat $TEMP
rm -f $TEMP
fi

return $retval
}

start() {
# Start daemons.
echo -n $"Starting $prog: "
daemon /usr/sbin/dhcpd ${DHCPDARGS}
RETVAL=$?
echo
[ $RETVAL -eq 0 ] && touch /var/lock/subsys/dhcpd
return $RETVAL
}

stop() {
# Stop daemons.
echo -n $"Shutting down $prog: "
killproc dhcpd
RETVAL=$?
echo
[ $RETVAL -eq 0 ] && rm -f /var/lock/subsys/dhcpd
return $RETVAL
}

# See how we were called.
case "$1" in
start)
start
;;
stop)
stop
;;
restart|reload)
configtest || exit $?
stop
start
RETVAL=$?
;;
condrestart)
if [ -f /var/lock/subsys/dhcpd ]; then
stop
start
RETVAL=$?
fi
;;
configtest)
configtest
RETVAL=$?
;;
status)
status dhcpd
RETVAL=$?
;;
*)
echo $"Usage: $0 {start|stop|restart|condrestart|configtest|status}"
exit 1
esac

exit $RETVAL