DHCP服务配置之主服务器配置

1.DHCP简介：

DHCP（Dynamic Host Configuration Protocol，动态主机配置协议）一般被应用在大型的局域网络环境中，主要做用是集中的管理、分配IP地址，使网络环境中的主机动态的得到IP地址、Gateway地址、DNS服务器地址等信息，并可以提高地址的使用率。

2.DHCP服务器简介:

DHCP服务器指的是由服务器控制一段IP地址范围，客户端登陆服务器时就能够自动得到服务器分配的IP地址和子网掩码。

3.安装DHCP软件

[root@localhost Server]# rpm -ivh dhcp-3.0.5-21.el5.x86_64.rpm

[root@localhost Server]# yum install   dhcp -y    

4.安装后DHCP生成的软件文件路径（部分）

[root@localhost Server]# rpm -ql dhcp
/etc/dhcpd.conf
/etc/rc.d/init.d/dhcpd
/etc/rc.d/init.d/dhcrelay
/etc/sysconfig/dhcpd
/etc/sysconfig/dhcrelay
/usr/bin/omshell
/usr/sbin/dhcpd（启动脚本）
/usr/sbin/dhcrelay
/usr/share/doc/dhcp-3.0.5/api+protocol
/usr/share/doc/dhcp-3.0.5/dhcpd.conf.sample（重点文件）
/var/lib/dhcpd/dhcpd.leases （租约文件）

5.配置文件说明

说明：CentOS 5.X之前的配置文件路径 是/etc/dhcpd.conf     新版的配置文件路径 是/etc/dhcp/dhcpd.conf

[root@localhost Server]#cat /etc/dhcpd.conf
# DHCP Server Configuration file.
# see /usr/share/doc/dhcp*/dhcpd.conf.sample （说明配置文件的模版路径 ）
[root@localhost Server]# cp /usr/share/doc/dhcp-3.0.5/dhcpd.conf.sample   /etc/dhcpd.conf

[root@localhost Server]# cat /etc/dhcpd.conf

#这部分是全局设置    

option domain-name"zzhz.com"; #设置"域名"体如今/etc/resolv.conf中的search

option domain-name-servers IP1, IP2;    # DNS设置，会修改客户端的/etc/resolv.conf

default-lease-time 259200;   租约时间

max-lease-time 518400;   最大租约时间

ddns-update-style none;  #也有这个值 interim; 

 ignore client-updates;

#subnet ：指定子网做用域(动态IP)

subnet 192.168.0.0 netmask 255.255.255.0 {

range dynamic-bootp 192.168.0.128 192.168.0.254;#地址范围  有使用这个range dynamic-BOOTP

option routers 192.168.0.1;   #网关

option subnet-mask 255.255.255.0; #子网掩码

 

option nis-domain "domain.org"; 

option broadcast-address 192.168.0.255;#广播地址

option time-offset -18000; #时区时间

option ntp-servers 192.168.1.1;

 option netbios-name-servers 192.168.1.1;

option netbios-node-type 2;

# 固定IP地址设置
　　host win7 {
　　hardware ethernet 12:34:56:78:AB:CD;
　　fixed-address 207.175.42.254;
　　}
}

6.重启服务和语法检查

[root@localhost Server]# service dhcpd restart
启动 dhcpd： [肯定]
[root@localhost Server]# service dhcpd configtest
Syntax: OK

7.防火墙设置

iptables -I INPUT 1 -p tcp tcp --dport 67  -j ACCEPT

iptables -I INPUT 1 -p tcp tcp --dport 68  -j ACCEPT

iptables -I INPUT 1 -p tcp udp --dport 67  -j ACCEPT

iptables -I INPUT 1 -p tcp udp --dport 68 -j ACCEPT

8.一些文件说明： 

tailf /var/log/messages   服务器端：显示客户端请求IP过程
Aug 21 16:13:45 localhost dhcpd: Sending on LPF/eth0/00:0c:29:52:2f:a0/192.168.80/24
Aug 21 16:13:45 localhost dhcpd: Sending on Socket/fallback/fallback-net
Aug 21 16:13:50 localhost dhcpd: DHCPREQUEST for 192.168.80.200 from 00:0c:29:b8:d1:2a via eth0
Aug 21 16:13:50 localhost dhcpd: DHCPACK on 192.168.80.200 to 00:0c:29:b8:d1:2a via eth0
Aug 21 16:14:02 localhost dhcpd: DHCPREQUEST for 192.168.80.200 from 00:0c:29:b8:d1:2a via eth0
Aug 21 16:14:02 localhost dhcpd: DHCPACK on 192.168.80.200 to 00:0c:29:b8:d1:2a via eth0
Aug 21 16:15:31 localhost dhcpd: DHCPDISCOVER from 00:0c:29:f4:21:01 via eth0
Aug 21 16:15:31 localhost dhcpd: DHCPOFFER on 192.168.80.199 to 00:0c:29:f4:21:01 via eth0
Aug 21 16:15:32 localhost dhcpd: DHCPREQUEST for 192.168.80.199 (192.168.80.100) from 00:0c:29:f4:21:01 via eth0
Aug 21 16:15:32 localhost dhcpd: DHCPACK on 192.168.80.199 to 00:0c:29:f4:21:01 via eth0

服务器端：显示分配过的IP信息

cat /var/lib/dhcpd/dhcpd.leases

客户端：显示客户端请求到的IP信息

cat /var/lib//dhclient/dhclient-eth0.leases

服务器端：若是有我个网卡，设置其中一个接受客户端DHCP请求接口

[root@localhost Server]# cat /etc/sysconfig/dhcpd 

DHCPDARGS="eht0"