最简单的DHCP服务

时间:2022-12-12 14:33:14

这几天在准备网络安装linux操作系统。最后决定用pxe + kickstart 的方式完成。原理、方案弄完了之后,开始搭建,结果被DHCP给挡住了。这不就得研究研究最简单最实用的DHCP使用方法。

   * 红色的是必须有

   * 绿色的是要注意

   * 蓝色的是包安装时,要有的程序包

 

           1. DHCP的实现

           2. 配置文件实例

               实例1

               实例2

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1. DHCP的实现

DHCP服务必须给本网段提供一个地址池。

# yum -y install dhcp-devel
# rpm -aq | grep dhcp
dhcp-4.1.-.P1.el6.centos.i686
dhcp-devel-4.1.-.P1.el6.centos.i686 # cp /usr/share/doc/dhcp-4.1./dhcpd.conf.sample /etc/dhcp/dhcpd.conf
# vi dhcpd.conf
ddns-update-style interim;
default-lease-time ;
max-lease-time ;
option domain-name “test.com”;
option domain-name-servers 192.168.1.1,202.106.0.20;
subnet 192.168.1.0 netmask 255.255. {
range 192.168.1.128 192.168.1.254;
option subnet-mask 255.255.255.0;
option routers 192.168.1.1;
} host server01 { hardware ethernet :c0:c3:::; fixed-address 192.168.1.11; option subnet-mask 255.255.255.0; option routers 192.168.1.1; } subnet 117.34.70.0 netmask 255.255.255.0 { default-lease-time ; max-lease-time ; option routers 117.34.70.1; option subnet-mask 255.255.255.0; }

一台主机有多块网卡,需要在某个网卡上启用DHCP服务时,需要配置如下:

# vi /etc/sysconfig/dhcpd
# Command line options here DHCPDARGS="eth0"

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2. 配置文件实例

简单的样例:(红色部分必须有)

# vi /etc/dhcp/dhcpd.conf
# dhcpd.conf
# Sample configuration file for ISC dhcpd
# option definitions common to all supported networks...
option domain-name "example.org";
option domain-name-servers ns1.example.org, ns2.example.org;
default-lease-time ;
max-lease-time ;
# Use this to enble / disable dynamic dns updates globally.
ddns-update-style none;
# If this DHCP server is the official DHCP server for the local
# network, the authoritative directive should be uncommented.
#authoritative;
# Use this to send dhcp log messages to a different log file (you also
# have to hack syslog.conf to complete the redirection).
log-facility local7; # No service will be given on this subnet, but declaring it helps the
# DHCP server to understand the network topology.
subnet 117.34.73.0 netmask 255.255.255.0 { } subnet 10.152.187.0 netmask 255.255.255.0 { } # vi /etc/dhcp/dhcpd.conf
default-lease-time ;
max-lease-time ;
ddns-update-style none;
subnet 117.34.73.0 netmask 255.255.255.0 { }

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* 注意:

● 如果主机网卡比较多,可以选择一块作为服务网卡。

vi /etc/sysconfig/dhcpd

# Command line options here
        DHCPDARGS="em1:1"
    ● 提供服务的网卡必需是 非自动获取 的地址。

ifconfig eth0 172.16.40.129/25 up

● 服务提供的地址池必需包含本地提供服务的地址在里面。

● 地址池(range)不能与作用域(subnet)冲突。

● 其他的参数、选项没有也可以启动的。所以可以不设置,因为这里是为了网络安装。

● 如果配置了这里所说的最简单的 dhcp 服务,却无法启动。就剩下一个原因,每句后面有没有分号。