一步輕鬆搞定DHCP服務器.

 搭建一個DNS服務器35秒那麼DHCP服務器呢.9秒就足能夠了

一個公司有大量的主機時一個一個的配置IP子網DNS.還不得配到吐血.有了DHCP服務器出現就能夠迎刃而解了,.它能夠動態分配IP.大大減小了管理員的工做量,並且能避免IP的衝突,而且節約IP(當IP不夠用時).可是如今你拉一條線人電信就給你配好了DHCP. 或者說我直接買個貓裏面就有DHCP功能. 還用本身搭建嗎??,

若是有多個部門的話.並且每一個部門的網段都不能同樣,這時用DHCP服務器就能夠大顯身手了,這裏單網段的DHCP服務器和多網段的DHCP服務器都搞定.

廢話很少說,開始搭建.

這個單網段的DHCP服務器我就不用拓撲圖了

簡單畫了個多網段的DHCP服務器拓撲:

 

搭建單網段的DHCP服務器:

說明一點:DHCP服務器linux和windows下還不同.分配IP的時候windows下是由小到大分配.而linux下是由大到小分配的

這裏提供腳本絕對可行。執行完你的DHCP服務器就能夠說OK了

#!/bin/bash mkdir /mafei mount /dev/cdrom  /mafei cd /mafei/Server rpm -ivh dhcp-3.0.5-3.el5.i386.rpm cp /usr/share/doc/dhcp-3.0.5/dhcpd.conf.sample /etc/dhcpd.conf  << MAFEI y MAFEI vi /etc/dhcpd.conf  << MAFEIFEI :%s/192.168.0.0/192.168.142.0/g :%s/192.168.0.128 192.168.0.254/192.168.142.129 192.168.142.254/g :%s/192.168.0.1/192.168.142.127/g :%s/192.168.1.1/192.168.142.128/g :wq MAFEIFEI service dhcpd restart chkconfig –level 35 dhcpd  on

 

下面提供具體操做過程

建立目錄將光盤掛載到指定目錄下在進行dhcp軟件包的安裝

 

[root@server ~]# mkdir /mafei [root@server ~]# mount /dev/cdrom /mafei mount: block device /dev/cdrom is write-protected, mounting read-only     [root@server Server]# rpm -ivh dhcp-3.0.5-3.el5.i386.rpm   warning: dhcp-3.0.5-3.el5.i386.rpm: Header V3 DSA signature: NOKEY, key ID 37017186 Preparing...                ########################################### [100%]    1:dhcp                   ########################################### [100%]

用模板將原文件覆蓋掉而後修改模板文件

要作多個網的話必須在原來DHCP服務器上添加一個要發佈的網段，

 

[root@server Server]# cp /usr/share/doc/dhcp-3.0.5/dhcpd.conf.sample /etc/dhcpd.conf cp：是否覆蓋「/etc/dhcpd.conf」? y [root@server Server]# vi /etc/dhcpd.conf   ddns-update-style none;    //關閉動態DNS更新模式   ignore client-updates;   subnet 192.168.142.0 netmask 255.255.255.0 {     //要發佈的網段（第一個要和本身一個網段不然會出錯得）       # --- default gateway           option routers                  192.168.142.127;  //要指定的網關         option subnet-mask              255.255.255.0;     //網關子網掩碼           option nis-domain               "domain.org";                  option domain-name              "domain.org";        //默認搜索區域         option domain-name-servers      192.168.142.128;        //DNS服務器的IP           option time-offset              -18000; # Eastern Standard Time   #       option ntp-servers              192.168.142.128; #       option netbios-name-servers     192.168.142.128; # --- Selects point-to-point node (default is hybrid). Don't change this unless # -- you understand Netbios very well #       option netbios-node-type 2;           range dynamic-bootp 192.168.142.129 192.168.142.254;  //要分佈的IP地址範圍         default-lease-time 21600;                         //默認租約時間         max-lease-time 43200;                            //最大租約時間           # we want the nameserver to appear at a fixed address           host ns {              //爲某個客戶機指定特定IP (ns爲自定義名稱,.在本文件中惟一存在)                 next-server marvin.redhat.com;                   hardware ethernet 12:34:56:78:AB:CD;  //綁定的客戶機max地址                 fixed-address 207.175.42.254;       //爲客戶機分配的IP地址         } } subnet 1.1.1.0 netmask 255.255.255.0 {           option routers                  1.1.1.1;         option subnet-mask              255.255.255.0;         range dynamic-bootp 1.1.1.3 1.1.1.222;         default-lease-time 21600;         max-lease-time 43200; }

啓動DHCP服務使服務器開始運行。

[root@server ~]# service dhcpd restart 關閉 dhcpd：                                               [失敗] 啓動 dhcpd：                                               [肯定]

 

 

 

 

默認仍是不要指了指了還容易出錯因此推薦不要作任何配置若是作dhcp中繼的話必須指

[root@server ~]# vi /etc/sysconfig/dhcpd # Command line options here DHCPDARGS=

在客戶機上先試一下能不能獲取到IP 能的話再作中繼否則 連DHCP服務器都沒搭出來後面也不用作了

仍是老規矩先隨便給同一網段的IP看是否能ping通，別犯低級錯誤。

 

搭建多網段的DHCP服務器  

其實比DHCP服務器的搭建多了一步就是在DHCP主配置文件中後面添加一個要指派的網段（這個網段必須和DHCP中繼服務器上的另外一個網卡在一個網段啊）

其實就是拷貝一下模板將原來的文件覆蓋掉而後再進行修改就好了 必要的時候指定一下使用哪一個接口就搞定了

注意一點:DHCP服務器的網關必須指向DHCP中繼服務器的IP不然會獲取不到IP的

一樣提供腳本一步搞定.連ip也OK了

#!/bin/bash LOCALIP=192.168.142.128 NETMASK=255.255.255.0 DHCPIP1=192.168.142.0 DHCPIP2=192.168.1.0 DHCPIP3=192.168.2.0 DHCPIPRANGE="192.168.142.130 192.168.142.254" DHCPIPRANGE2="192.168.1.5 192.168.1.253" DHCPIPRANGE3="192.168.2.5 192.168.2.253" DHCPROUTE=192.168.142.127 DHCPROUTE2=192.168.1.1 DHCPROUTE3=192.168.2.1 DNSIP=192.168.142.128 DNSNAME=www.mafei.com NETMASK=255.255.255.0 ETH0=/etc/sysconfig/network-scripts/ifcfg-eth0 echo "# Advanced Micro Devices [AMD] 79c970 [PCnet32 LANCE]" > $ETH0 echo "DEVICE=eth0" >> $ETH0 echo "ONBOOT=yes" >> $ETH0 echo "TYPE=Ethernet" >> $ETH0 echo "IPADDR=$LOCALIP" >> $ETH0 echo "NETMASK=$NETMASK" >> $ETH0 echo "GATEWAY=$DHCPROUTE" >> $ETH0 service network restart   mkdir /mafei mount /dev/cdrom /mafei cd /mafei/Server rpm -ivh /mafei/Server/dhcp-3.0.5-3.el5.i386.rpm cp /usr/share/doc/dhcp-3.0.5/dhcpd.conf.sample /etc/dhcpd.conf << MAFEI y MAFEI vi /etc/dhcpd.conf << MYMAFEI :%s/ddns-update-style interim/ddns-update-style none :%s/subnet 192.168.0.0 netmask 255.255.255.0/subnet $DHCPIP1 netmask 255.255.255.0 :%s/192.168.0.1;/$DHCPROUTE; :%s/range dynamic-bootp 192.168.0.128 192.168.0.254;/range dynamic-bootp $DHCPIPRANGE; :wq! MYMAFEI service dhcpd restart   echo "subnet $DHCPIP2 netmask 255.255.255.0 {" >> /etc/dhcpd.conf echo "        option routers                  $DHCPROUTE2;" >> /etc/dhcpd.conf echo "        option subnet-mask              $NETMASK;" >> /etc/dhcpd.conf echo "#        option nis-domain               "$DNSNAME";" >> /etc/dhcpd.conf echo "#        option domain-name              "$DNSNAME";" >> /etc/dhcpd.conf echo "#        option domain-name-servers      $DNSIP;" >> /etc/dhcpd.conf echo "        range dynamic-bootp $DHCPIPRANGE2;" >> /etc/dhcpd.conf echo "        default-lease-time 21600;" >> /etc/dhcpd.conf echo "        max-lease-time 43200;" >> /etc/dhcpd.conf echo "}" >> /etc/dhcpd.conf       service dhcpd restart   echo "subnet $DHCPIP3 netmask 255.255.255.0 {" >> /etc/dhcpd.conf echo "        option routers                  $DHCPROUTE3;" >> /etc/dhcpd.conf echo "        option subnet-mask              $NETMASK;" >> /etc/dhcpd.conf echo "#        option nis-domain               "$DNSNAME";" >> /etc/dhcpd.conf echo "#        option domain-name              "$DNSNAME";" >> /etc/dhcpd.conf echo "#        option domain-name-servers      $DNSIP;" >> /etc/dhcpd.conf echo "        range dynamic-bootp $DHCPIPRANGE3;" >> /etc/dhcpd.conf echo "        default-lease-time 21600;" >> /etc/dhcpd.conf echo "        max-lease-time 43200;" >> /etc/dhcpd.conf echo "}" >> /etc/dhcpd.conf service dhcpd restart chkconfig --level 35 dhcpd on

DHCP中繼服務器的搭建  

在中繼服務器上作的配置：

1.       開啓服務器的路由轉發功能

編輯「/etc/dhcpd.conf」將net.ipv4.ip_forward = 0改成net.ipv4.ip_forward = 1開啓路由功能，並執行sysctl –p 命令使配置生效

[root@server Server]# vi /etc/sysctl.conf net.ipv4.ip_forward = 1 [root@server Server]# sysctl -p net.ipv4.ip_forward = 1 net.ipv4.conf.default.rp_filter = 1 net.ipv4.conf.default.accept_source_route = 0 kernel.sysrq = 0 kernel.core_uses_pid = 1 net.ipv4.tcp_syncookies = 1 kernel.msgmnb = 65536 kernel.msgmax = 65536 kernel.shmmax = 4294967295 kernel.shmall = 268435456

 

 

 

若是沒有這個文件的話不用慌，那是你DHCP軟件包沒安裝上。再安一遍就搞定了

[root@server Server]# vi /etc/sysconfig/dhcrelay # Command line options here INTERFACES="eth0  eth1 eth2" DHCPSERVERS="192.168.142.127"

 

 

 

[root@server Server]# service dhcrelay restart Shutting down dhcrelay:                                    [FAILED] Starting dhcrelay: Internet Systems Consortium DHCP Relay Agent V3.0.5-RedHat Copyright 2004-2006 Internet Systems Consortium. All rights reserved. For info, please visit http://www.isc.org/sw/dhcp/ Listening on LPF/eth1/00:0c:29:c1:ef:89 Sending on   LPF/eth1/00:0c:29:c1:ef:89 Listening on LPF/eth0/00:0c:29:c1:ef:7f Sending on   LPF/eth0/00:0c:29:c1:ef:7f Sending on   Socket/fallback                                                            [  OK  ] [root@server Server]# chkconfig --level 35 dhcrelay on

 

調整客戶機的網段。我用的是虛擬機因此你用跳到和中繼的2網卡在同一網段便可若是在現實中直接跳到另外一個路由口上就 行了、

 

 

 

 

 

 

 

3.       啓動dhcrelay中繼服務程序。並設置開機自動啓動

 

2.       設置容許DHCP中繼數據的接口及DHCP服務器的ip地址

 

指定DHCP服務器提供服務的接口