实验
#client添加一个NAT网卡
让客户端能通过这张网卡和 DHCP 服务器通信，获取 IP 地址
#安装，服务器就具备了分配 IP 地址的功能
[root@server ~ 10:39:21]# yum install -y dhcp
#复制 DHCP 配置模板
[root@server ~ 10:44:20]# cp /usr/share/doc/dhcp-*/dhcpd.conf.example /etc/dhcp/dhcpd.conf
cp：是否覆盖"/etc/dhcp/dhcpd.conf"？ yes
#进入vim编辑套用cp过来的模板，删除只留以下内容，修改ip等。
[root@server ~ 10:50:24]# vim /etc/dhcp/dhcpd.conf
=======================================================================
# A slightly different configuration for an internal subnet.
subnet 10.1.8.0 netmask 255.255.255.0 { ## 配置一个内网子网
range 10.1.8.101 10.1.8.200; ## 可分配的IP范围（从101到200）
option domain-name-servers 223.5.5.5,223.6.6.6;## 给客户端的DNS服务器（阿里云的）
option domain-name "lyk.cloud"; ## 客户端的域名（类似网址的后缀）
option routers 10.1.8.2; ## 客户端的网关（上网的出口）
option broadcast-address 10.1.8.255; ## 广播地址（子网内群发消息用）
default-lease-time 600; ## 默认租约时间（10分钟，到期前会自动续租）
max-lease-time 7200; ## 最长租约时间（2小时，到期不续租就收回IP）
}
# Fixed IP addresses can also be specified for hosts. These addresses
# should not also be listed as being available for dynamic assignment.
# Hosts for which fixed IP addresses have been specified can boot using
# BOOTP or DHCP. Hosts for which no fixed address is specified can only
# be booted with DHCP, unless there is an address range on the subnet
# to which a BOOTP client is connected which has the dynamic-bootp flag
# set.
host fantasia {
hardware ethernet 08:00:07:26:c0:a5;
fixed-address fantasia.fugue.com;
}
=======================================================================
#重启 DHCP 服务
[root@server ~ 10:55:45]# systemctl restart dhcpd
#客户端配置：删除旧连接
[root@client ~ 11:15:33]# nmcli c
NAME UUID TYPE DEVICE
ens33 555eece5-af4c-45ae-bab9-c07e68d0e649 ethernet ens33
有线连接 1 04c7e0b9-f265-361a-a91c-7e37f6c4f527 ethernet ens36
[root@client ~ 11:15:36]# nmcli connection delete 有线连接\ 1
成功删除连接 "有线连接 1" (04c7e0b9-f265-361a-a91c-7e37f6c4f527)
[root@client ~ 11:18:14]# nmcli c
NAME UUID TYPE DEVICE
ens33 555eece5-af4c-45ae-bab9-c07e68d0e649 ethernet ens33
#客户端配置：新建 DHCP 连接
[root@client ~ 11:18:17]# nmcli connection add type ethernet ifname ens36 con-name ens36-dhcp
连接 "ens36-dhcp" (062eb6de-947c-4b98-ab83-29b936ecacb2) 已成功添加
#服务器配置：查找给客户端分配固定 IP
[root@client ~ 11:19:08]# nmcli c
NAME UUID TYPE DEVICE
ens33 555eece5-af4c-45ae-bab9-c07e68d0e649 ethernet ens33
ens36-dhcp 062eb6de-947c-4b98-ab83-29b936ecacb2 ethernet ens36
#ens36 UP #复制 00:0c:29:b1:07:43 <BROADCAST,MULTICAST,UP,LOWER_UP>
#进入server
[root@server dhcp 11:40:10]# vim /etc/dhcp/dhcpd.conf
#进入vim编辑
host client {
hardware ethernet 00:0c:29:b1:07:43; #粘贴替换
fixed-address 10.1.8.88; #10.1.8.88
}
[root@server dhcp 11:43:57]# systemctl restart dhcpd
#回到client端查看
[root@client ~ 11:42:47]# nmcli connection up ens36-dhcp
连接已成功激活（D-Bus 活动路径：/org/freedesktop/NetworkManager/ActiveConnection/3）
[root@client ~ 11:46:12]# ip -br a
lo UNKNOWN 127.0.0.1/8 ::1/128
ens33 UP 10.1.8.11/24 fe80::20c:29ff:feb1:739/64
ens36 UP 10.1.8.88/24 fe80::bda6:a0cf:90eb:59ac/64