centos7搭建DHCP

前期准备

DHCP（动态主机配置协议）是一个局域网的网络协议。指的是由服务器控制一段lP地址范围，客户机登录服务器时就可以自动获得服务器分配的lP地址和子网掩码。默认情况下，DHCP作为Windows Server的一个服务组件不会被系统自动安装，还需要管理员手动安装并进行必要的配置。
准备两台虚拟机：
192.168.43.11 （服务端）
客户端 （最后验证需要）

---

服务端

配置网卡模式

重启网卡使配置生效：systemctl restart network
查看生效的网卡配置：ifconfig ens33
[root@localhost ~]# ifconfig ens33
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.43.11  netmask 255.255.255.0  broadcast 192.168.43.255
        inet6 fe80::963a:9ac6:910d:70f2  prefixlen 64  scopeid 0x20<link>
        inet6 fe80::dcd6:5415:c2cc:5266  prefixlen 64  scopeid 0x20<link>
        ether 00:0c:29:4e:7a:5e  txqueuelen 1000  (Ethernet)
        RX packets 1420  bytes 118479 (115.7 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 1003  bytes 154595 (150.9 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

安装DHCP

查看本机是否安装DHCP
rpm -qa dhcp
若无则安装
yum -y install dhcp

配置DHCP

vim /etc/dhcp/dhcpd.conf
打开发现里边没有配置文件：
# DHCP Server Configuration file.
#   see /usr/share/doc/dhcp*/dhcpd.conf.example
#   see dhcpd.conf(5) man page
此时可根据提示复制提到的文件内容：
cp /usr/share/doc/dhcp*/dhcpd.conf.example /etc/dhcp/dhcpd.conf 
cp: overwrite ‘/etc/dhcp/dhcpd.conf’? y
vim /etc/dhcp/dhcpd.conf
修改以下内容：
 47 subnet 192.168.43.0 netmask 255.255.255.0 {                // 此处为网段和子网掩码
 48   range 192.168.43.20 192.168.43.100;                      //此处为分配的IP地址
 49   option domain-name-servers ns1.internal.example.org;
 50   option domain-name "internal.example.org";
 51   option routers 192.168.43.1;                             //选择路由器
 52   option broadcast-address 192.168.43.255;                 //广播地址
 53   default-lease-time 600;                                  //租赁时间
 54   max-lease-time 7200;                                     //最长租赁时间
 55 }
 重启DHCP服务：
 systemctl restart dhcpd
 查看端口号：
netstat -anput |grep dhcpd
udp        0      0 0.0.0.0:42967           0.0.0.0:*                           2893/dhcpd          
udp        0      0 0.0.0.0:67              0.0.0.0:*                           2893/dhcpd          
udp6       0      0 :::4900                 :::*                                2893/dhcpd  

客户端1

配置网卡模式

vim /etc/sysconfig/network-scripts/ifcfg-ens33
只修改以下内容：
BOOTPROTO="dhcp"

重启网卡使配置生效：systemctl restart network
查看生效的网卡配置：ifconfig ens33
[root@localhost ~]# ifconfig ens33
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.43.20  netmask 255.255.255.0  broadcast 192.168.43.255
        inet6 fe80::963a:9ac6:910d:70f2  prefixlen 64  scopeid 0x20<link>
        ether 00:0c:29:a0:f2:9e  txqueuelen 1000  (Ethernet)
        RX packets 816  bytes 87169 (85.1 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 375  bytes 56319 (54.9 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

客户端2

指定IP

vim /etc/sysconfig/network-scripts/ifcfg-ens33
TYPE="Ethernet"
BOOTPROTO="dhcp"
DEFROUTE="yes"
PEERDNS="yes"
PEERROUTES="yes"
IPV4_FAILURE_FATAL="no"
IPV6INIT="yes"
IPV6_AUTOCONF="yes"
IPV6_DEFROUTE="yes"
IPV6_PEERDNS="yes"
IPV6_PEERROUTES="yes"
IPV6_FAILURE_FATAL="no"
IPV6_ADDR_GEN_MODE="stable-privacy"
NAME="ens33"
UUID="eee486ed-8277-4228-9134-fe49d69cd80c"
DEVICE="ens33"
ONBOOT="yes"

把客户机的MAC地址写到服务器的配置文件中

vim /etc/dhcp/dhcpd.conf
修改以下内容：
 75 host fantasia {
 76   hardware ethernet 00:0c:29:7d:b4:48;
 77   fixed-address 192.168.43.51;
 78 }
 重启DHCP：systemctl restart dhcpd

ifconfig ens33
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.43.13  netmask 255.255.255.0  broadcast 192.168.43.255
        inet6 fe80::654a:14a9:3f08:bbad  prefixlen 64  scopeid 0x20<link>
        inet6 fe80::963a:9ac6:910d:70f2  prefixlen 64  scopeid 0x20<link>
        inet6 fe80::dcd6:5415:c2cc:5266  prefixlen 64  scopeid 0x20<link>
        ether 00:0c:29:7d:b4:48  txqueuelen 1000  (Ethernet)
        RX packets 498  bytes 41888 (40.9 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 340  bytes 39381 (38.4 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0




dhclient -r ens33                                      //释放租约时间
dhclient                                               //重新分配IP
ifconfig ens33                                         //查看新的IP
ifconfig ens33
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.43.51  netmask 255.255.255.0  broadcast 192.168.43.255
        inet6 fe80::654a:14a9:3f08:bbad  prefixlen 64  scopeid 0x20<link>
        inet6 fe80::963a:9ac6:910d:70f2  prefixlen 64  scopeid 0x20<link>
        inet6 fe80::dcd6:5415:c2cc:5266  prefixlen 64  scopeid 0x20<link>
        ether 00:0c:29:7d:b4:48  txqueuelen 1000  (Ethernet)
        RX packets 915  bytes 80087 (78.2 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 747  bytes 89727 (87.6 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

来源：CSDN

作者：suiyu_eran_

链接：https://blog.csdn.net/suiyu_eran_/article/details/103833644