簡單配置DHCP服務器
DHCP：動態主機設定協定（Dynamic Host Configuration Protocol）是一個局域網的網絡協議，使用UDP協議工作，主要有兩個用途：
(1).給內部網絡或網絡服務供應商自動分配IP地址給用戶
(2).給內部網絡管理員作爲對所有電腦作中央管理的手段
說明：
dhcp服務不能垮網段，也不能用於外網，只能用於內網環境中
在一個內網網段中，只允許有一臺dhcp服務器，不允許出現2臺或多臺，否則會出現衝突導致dhcp服務不能正常使用。
具體配置：
1.在服務器端:
[root@localhost ~]# rpm -q dhcp package dhcp is not installed #此時發現沒有安裝dhcp # yum install dhcp –y [root@localhost ~]# cat /etc/dhcpd.conf
#
# DHCP Server Configuration file.
# see /usr/share/doc/dhcp*/dhcpd.conf.sample
# cd /usr/share/doc/dhcp-3.0.5/ # cp dhcpd.conf.sample /etc/dhcpd.conf # cd
下面是一個配置實例：
# vim /etc/dhcpd.conf ddns-update-style interim; ignore client-updates; subnet 172.16.0.0 netmask 255.255.0.0 { # --- default gateway option routers 172.16.1.1; option subnet-mask 255.255.0.0; option nis-domain "domain.org"; option domain-name "domain.org"; option domain-name-servers 172.16.1.1; option time-offset -18000; # Eastern Standard Time # option ntp-servers 172.16.1.1; # option netbios-name-servers 172.16.1.1; # --- 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 172.16.0.1 172.16.55.254; default-lease-time 21600; max-lease-time 43200; # we want the nameserver to appear at a fixed address host ns { next-server marvin.redhat.com; hardware ethernet 12:34:56:78:AB:CD; fixed-address 207.175.42.254; } }說明：
subnet 172.16.0.0 netmask 255.255.0.0 # 設置子網聲明
option routers 172.16.1.1; #爲DHCP客戶設置默認網關爲172.16.1.1
option subnet-mask 255.255.0.0; #爲DHCP客戶設置子網掩碼爲255.255.0.0
option domain-name-servers 172.16.1.1; #爲DHCP客戶設置DNS域爲172.16.1.1
range dynamic-bootp 172.16.0.1 172.16.0.254; #爲DHCP客戶設置自動獲取的IP地址範圍
default-lease-time 21600; #爲DHCP客戶設置默認地址租期
max-lease-time 43200; #爲DHCP客戶設置最大地址租期
# service dhcpd start
2.在客戶端：
[root@lihuan ~]# rpm -q dhcp
package dhcp is not installed
確保在客戶端沒有安裝dhcp軟件
# vim /etc/sysconfig/network-scripts/ifcfg-eth0
把”BOOTPROTO=static”改爲”BOOTPROTO=dhcp”
# service network restart