linux配置dhcp

DHCP服务配置
        安装 （linux安装光盘的第2张）
                  #mount  /mnt/cdrom
                  #cd /mnt/cdrom/Red Hat/RPMS
                  #rpm -ivh dhcp-3.0pl1-23.i386.rpm
       相关文件和目录 
                 /etc/rc.d/init.d/dhcp                     //DHCP的服务启动脚本
                 /etc/dhcpd.conf                           //核心配置文件 （默认下没这文件，须要在下面说明文档的dhcpd.conf.sample文件）
                 /usr/share/doc/dhcp-3.0pl           //存放DHCP说明文档
                 /etc/sysconfig/dhcpd                   //配置DHCP启动参数
                 /etc/sysconfig/dhcrelay/               //配置DHCP中继代理
                 /var/lib/dhcp/dhcp.leaser             //客户租约的数据库文件
       文件解析
                /etc/dhcpd.conf  
                功能：配置DHCP服务器
                文件格式：       全局参数                                                           .....          
                                                 声明{
                                                         ......
                                                          局部选项
                                                         ......  
                                                         }
（1）声明
               subnet                                             -功能：定义子网（定义作用域）
                                                                     -格式：subnet  网络号  netmask  子网掩码{ 选项 ;  参数 ；}

               host                                                - 攻能：为指定的客户机提供IP信息
                                                                     - 格式：host 名称 { 选项 ； 参数 ；}
                                                                     - 注意：通常放在subnet声明中
      （2）参数
                ddns-updata-style                          -功能：定义DNS更新方案
                                                                     - 格式：ddns-updata-style {none/interim}
                                                                     -注意：在文件中必须包含该参数。且放在第一行

               ignore                                             - 功能：忽略客户机更新 
                                                                      - 格式：ignore client-updates；
                                                                     - 注意：该选项只能作为全局选项

               default-lease-time                           - 功能：指定默认租约时间
                                                                     -格式：default-lease-time 数字（时间）
                                                                                           - 注意：可以作为全局选项和局部选项，默认单位为秒

              max-lease-time                                - 功能：指定最长的地址租期 
                                                                    - 格式：max-lease-time   数字（时间）
                                                                                          - 注意：可以作为全局选项和局部选项，默认单位为秒

              hardware                                       - 功能：指定硬件接口类型及硬件地址
                                                                    - 格式：hardware 硬件类型 硬件地址
                                                                    - 注意：硬件地址为网卡的MAC地址，该选项只能用于host声明

              fixed-address                                 - 功能：定义保留IP地址                                               
                                                                    - 格式：fixed-address IP地址
                                                                    - 注意：该选项只能用于host声明中

              range                                             - 功能：定义作用域范围
                                                                   - 格式：range  起始IP地址 终止IP地址
                                                                  - 注意：用于subnet声明，一个subnet中可以有多个range，所定义IP不能重复
        （3）选项
              options routers                              -功能：为客户机指定默认网关
                                                                  - 格式：options routers  IP地址 [IP地址·......]
                                                                   - 注意：可以作为全局选项和局部选项      
        
              options romain-name-servers       -功能：指定客户机的DNS服务器地址
                                                                 - 格式：options romain-name-servers  IP地址 [IP地址·......]
                                                                 - 注意：可以作为全局选项和局部选项

             options domain-name                    -功能：定义客户端DNS后缀名
                                                                 - 格式：options domain-name  “域名”
                                                                 - 注意：可以作为全局选项和局部选项 

              options-mask                               -功能：定义客户机的子网掩码  
                                                                  - 格式：options-mask 子网掩码
                                                                 - 注意：可以作为全局选项和局部选项

例子：