DHCP

术语

作用域：一个完整的IP地址段，DHCP协议根据作用域来管理网络的分布、分配IP地址及其他配置参数

超级作用域：用于管理处于同一个物理网络中的多个逻辑子网段。超级作用域中包含了可以统一管理的作用域列表

排除范围：把作用域中的某些IP地址排除，确保这些IP地址不会分配给DHCP客户端

地址池：在定义了DHCP的作用域并应用了排除范围后，剩余的用来动态分配给DHCP客户端的IP地址范围

租约：DHCP客户端能够使用动态分配的IP地址的时间

预约：保证网络中的特定设备总是获取到相同的IP地址

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
yum install dhcp
Loaded plugins: langpacks, product-id, subscription-manager
This system is not registered to Red Hat Subscription Management. You can use 
subscription-manager to register.
rhel | 4.1 kB 00:00 
Resolving Dependencies
--> Running transaction check
---> Package dhcp.x86_64 12:4.2.5-27.el7 will be installed
--> Finished Dependency Resolution
Dependencies Resolved
===============================================================================
 Package Arch Version Repository Size
===============================================================================
Installing:
 dhcp x86_64 12:4.2.5-27.el7 rhel 506 k
Transaction Summary
===============================================================================
Install 1 Package
Total download size: 506 k
Installed size: 1.4 M
Is this ok [y/d/N]: y
Downloading packages:
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
 Installing : 12:dhcp-4.2.5-27.el7.x86_64 1/1 
 Verifying : 12:dhcp-4.2.5-27.el7.x86_64 1/1 
Installed:
 dhcp.x86_64 12:4.2.5-27.el7 
Complete!

cat /etc/dhcp/dhcpd.conf
# DHCP Server Configuration file.
# see /usr/share/doc/dhcp*/dhcpd.conf.example
# see dhcpd.conf(5) man page

dhcpd参数

参数作用
ddns-update-style-[类型]定义DNS服务动态更新的类型，类型包括none（不支持动态更新）、interim（互动更新模式）与ad-hoc（特殊更新模式）
`[allowignore]_client-updates`允许/忽略客户端更新DNS记录
default-lease-time_[21600]默认超时时间
max-lease-time_[43200]最大超时时间
option_domain-name-servers_[8.8.8.8]定义DNS服务器地址
option_domain-name_["domain.org"]定义DNS域名
range定义用于分配的IP地址池
option_subnet-mask定义客户端的子网掩码
option-routers定义客户端的网关地址
broadcase-address[广播地址]定义客户端的广播地址
ntp-server[IP地址]定义客户端的网络时间服务器（NTP）
nis-servers[IP地址]定义客户端的NIS域服务器的地址
Hardware[网卡物理地址]指定网卡接口的类型与MAC地址
server-name[主机名]向DHCP客户端通知DHCP服务器的主机名
fixed-address[IP地址]将某个固定的IP地址分配给指定主机
time-offset[偏移误差]指定客户端与格林尼治时间的偏移差

机房网络信息

参数名称值
默认租约时间21600秒
最大租约时间43200秒
IP地址范围192.168.10.50～192.168.10.150
子网掩码255.255.255.0
网关地址192.168.10.1
DNS服务器地址192.168.10.1
搜索域linuxprobe.com

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
vim /etc/dhcp/dhcpd.conf
ddns-update-style none;
ignore client-updates;
subnet 192.168.10.0 netmask 255.255.255.0 {
range 192.168.10.50 192.168.10.150;
option subnet-mask 255.255.255.0;
option routers 192.168.10.1;
option domain-name "linuxprobe.com";
option domain-name-servers 192.168.10.1;
default-lease-time 21600;
max-lease-time 43200;
}

dhcpd参数

参数作用
ddns-update-style_none;设置DNS服务不自动进行动态更新
ignore_client-updates;忽略客户端更新DNS记录
subnet-192.168.10.0-netmask-255.255.255.0-{作用域为192.168.10.0/24网段
range-192.168.10.50-192.168.10.150;IP地址池为192.168.10.50-150（约100个IP地址）
option_subnet-mask_255.255.255.0;定义客户端默认的子网掩码
option-routers-192.168.10.1;定义客户端的网关地址
option-domain-name-"linuxprobe.com";定义默认的搜索域
option_domain-name-servers_192.168.10.1;定义客户端的DNS地址
default-lease-time_21600;定义默认租约时间（单位：秒）
max-lease-time_43200;定义最大预约时间（单位：秒）
}结束符

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
systemctl start dhcpd
systemctl enable dhcpd
ln -s '/usr/lib/systemd/system/dhcpd.service' '/etc/systemd/system/multi-user.target.wants/dhcpd.service'

#分配固定ip
tail -f /var/log/messages 
Mar 30 05:33:17 localhost dhcpd: Copyright 2004-2013 Internet Systems Consortium.
Mar 30 05:33:17 localhost dhcpd: All rights reserved.
Mar 30 05:33:17 localhost dhcpd: For info, please visit https://www.isc.org/
software/dhcp/
Mar 30 05:33:17 localhost dhcpd: Not searching LDAP since ldap-server, ldap-
port and ldap-base-dn were not specified in the config file
Mar 30 05:33:17 localhost dhcpd: Wrote 0 leases to leases file.
Mar 30 05:33:17 localhost dhcpd: Listening on LPF/eno16777728/00:0c:29:c4:a4:
09/192.168.10.0/24
Mar 30 05:33:17 localhost dhcpd: Sending on LPF/eno16777728/00:0c:29:c4:a4:09/
192.168.10.0/24
Mar 30 05:33:17 localhost dhcpd: Sending on Socket/fallback/fallback-net
Mar 30 05:33:26 localhost dhcpd: DHCPDISCOVER from 00:0c:29:27:c6:12 via eno16777728
Mar 30 05:33:27 localhost dhcpd: DHCPOFFER on 192.168.10.50 to 00:0c:29:27:c6:
12 (WIN-APSS1EANKLR) via eno16777728
Mar 30 05:33:29 localhost dhcpd: DHCPDISCOVER from 00:0c:29:27:c6:12 (WIN-
APSS1EANKLR) via eno16777728
Mar 30 05:33:29 localhost dhcpd: DHCPOFFER on 192.168.10.50 to 00:0c:29:27:c6:
12 (WIN-APSS1EANKLR) via eno16777728
Mar 30 05:33:29 localhost dhcpd: DHCPREQUEST for 192.168.10.50 (192.168.10.10)
from 00:0c:29:27:c6:12 (WIN-APSS1EANKLR) via eno16777728
Mar 30 05:33:29 localhost dhcpd: DHCPACK on 192.168.10.50 to 00:0c:29:27:c6:12
(WIN-APSS1EANKLR) via eno16777728

vim /etc/dhcp/dhcpd.conf 
 1 ddns-update-style none;
 2 ignore client-updates;
 3 subnet 192.168.10.0 netmask 255.255.255.0 {
 4 range 192.168.10.50 192.168.10.150;
 5 option subnet-mask 255.255.255.0;
 6 option routers 192.168.10.1;
 7 option domain-name "linuxprobe.com";
 8 option domain-name-servers 192.168.10.1;
 9 default-lease-time 21600;
 10 max-lease-time 43200;
 11 host linuxprobe {
 12 hardware ethernet 00:0c:29:27:c6:12;
 13 fixed-address 192.168.10.88;
 14 }
 15 }

systemctl restart dhcpd

Copyright ©2010-2022 比特日记 All Rights Reserved.

浙ICP备11005866号-12