RH253Linux服务器架设笔记四-DHCP服务器配置.doc

RH253Linux服务器架设笔记四-DHCP服务器配置今天我们的课程是DHCP服务器的架设,在安装虚拟机的时候网卡选择桥接的就可以.DHCP基于客户/服务器模式。当DHCP客户端启动时，它会自动与DHCP服务器通信，由DHCP服务器为DHCP客户端提供自动分配IP地址的服务。 当然高级的DHCP，不光只是分配地址这么简单,今天我们的课程只是架设一个普通的DHCP的服务器, client端能获取到上网必须的网络配置信息安装了DHCP服务软件的服务器称为DHCP服务器，而启用了DHCP功能的客户机称为DHCP客户端,DHCP服务器是以地址租约的方式为DHCP客户端提供服务的，它有以下两种方式。 限定租期 永久租用学DHCP服务器，就一定要知道DHCP服务器的工作原理,不然你就白学了 DHCPDISCOVER（DHCP发现） DHCPOFFER（DHCP提供） DHCPREQUEST（DHCP请求） DHCPACK（DHCP确认）这个4个步骤，是client获取IP地址必经的步骤 在第二步，DHCP提供的时候，服务器已经给client分配了IP地址,第二部分分给client的IP地址是临时的，client得到这个 IP地址后，会发出DHCP请求,请求租用这个地址，服务器收到请求后，就会正式把这个地址分配给client，继而向client发送DHCP确认。 这个四步主要是应对同一网络多个DHCP服务器后台进程：dhcpd 脚本：/etc/rc.d/init.d/dhcpd 使用端口：67 所需RPM包：dhcp 相关RPM包： dhcp-devel-3.0.5-7.el5.i386.rpm dhcpv6-0.10-33.el5.i386.rpm dhcpv6_client-0.10-33.el5.i386.rpm 配置文件：/etc/dhcpd.conf 日志：/var/log/xferlog68号是网络启动模式使用的,暂时不讨论再提示一点吧，网络启动方式也叫bootpc，这样获取的IP地址是不会受服务器的租期限制的，它永远有效 好了，我们先安装DHCP服务器 编辑DHCP的主配置文件vim /etc/dhcpd.conf这里的意思是see的路劲是一个模板 我们把这个文件内容导进来,在末行模式运行以下命令 末行模式使用 :r 文件名:r /usr/share/doc/dhcp*/dhcpd.conf.sample这样模板就被导入进来了使用模板的好处 第一自己写配置文件，麻烦还容易出错 第二使用模板架设很快，只需要修改几个参数就OK了ddns-update-style 类型 定义所支持的DNS动态更新类型（必选）,一般我们设置成关闭,interim和none都是关闭的意思 allow/ignore client-updates 允许/忽略客户机更新DNS记录 subnet 网络号 netmask 子网掩码 定义作用域（或IP子网）配置文件已经说的很清楚了 option routers ,网关，我的网关是 nis-domain 局域网内有nis服务器的，可以设置nis服务器的域名我没有架设nis服务器，所以这行可以注释了 下一行是domain-name，域名 我的是 域名服务器是我这个机器的IP，linux当然有超级域,linux也能实现中继DHCP,相关设置参考RHEL5企业级Linux服务攻略-第3季 DHCP服务全攻略time-offset：为客户端指定格林威治时间偏移时间，单位秒，该选项可以在全局配置、局部配置均可使用。 ntp-servers：NTP是时间服务器 netbios-name-servers：是微软的名字服务器 NTP服务器，你可以设置一个外网的，如果觉得没必要就可以不设置range dynamic-bootp 就是动态分配的IP地址池，这个是IP地址是连在一起的地址池范围下面两行是默认租期和最大租期，单位是秒 如果你某个主机要固定获取某个IP，就可以使用下面的功能，next-server 这里用不上，意思就是下一个服务器，一般指向tftp的，一般是PXE网络使用这个参数 好了，保存退出 重新启动服务记住，配置文件中的一定要对应，还有第一个参数ddns-update-styple 必须要，一般就不会出什么问题了看下日志 cat /var/log/messagesrootrhel5 # cat /var/log/messages Mar 22 04:02:10 rhel5 syslogd 1.4.1: restart. Mar 22 04:02:09 rhel5 nmbd24089: 2009/03/22 04:02:09, 0 nmbd/nmbd_workgroupdb.c:dump_workgroups(282) Mar 22 04:02:09 rhel5 nmbd24089: dump_workgroups() Mar 22 04:02:09 rhel5 nmbd24089: dump workgroup on subnet 88: netmask= : Mar 22 04:02:09 rhel5 nmbd24089: WANXUAN(7) current master browser = SERVER Mar 22 04:02:09 rhel5 nmbd24089: WORKGROUP(6) current master browser = LENOVO-A5A67FC0 Mar 22 04:02:09 rhel5 nmbd24089: MYGROUP(1) current master browser = RHEL5 Mar 22 04:02:09 rhel5 nmbd24089: RHEL5 40849a03 (Samba Server Version 3.0.25b-0.el5.4) Mar 22 08:38:43 rhel5 kernel: VFS: busy inodes on changed media. Mar 22 08:38:49 rhel5 last message repeated 7 times Mar 22 08:48:06 rhel5 scim-bridge: Panel client has not yet been prepared Mar 22 08:48:09 rhel5 Panel client has not yet been prepared Mar 22 08:48:09 rhel5 scim-bridge: Panel client has not yet been prepared Mar 22 08:53:07 rhel5 kernel: VFS: busy inodes on changed media. Mar 22 08:53:38 rhel5 last message repeated 33 times Mar 22 08:54:21 rhel5 last message repeated 42 times Mar 22 13:27:30 rhel5 Panel client has not yet been prepared Mar 22 13:27:30 rhel5 scim-bridge: Panel client has not yet been prepared Mar 22 13:29:09 rhel5 nmbd24089: 2009/03/22 13:29:09, 0 nmbd/nmbd.c:terminate(58) Mar 22 13:29:09 rhel5 nmbd24089: Got SIGTERM: going down. Mar 22 13:34:09 rhel5 nmbd18273: 2009/03/22 13:34:09, 0 nmbd/nmbd.c:terminate(58) Mar 22 13:34:09 rhel5 nmbd18273: Got SIGTERM: going down. Mar 22 13:39:51 rhel5 nmbd18445: 2009/03/22 13:39:51, 0 nmbd/nmbd_become_lmb.c:become_local_master_stage2(396) Mar 22 13:39:51 rhel5 nmbd18445: * Mar 22 13:39:51 rhel5 nmbd18445: Mar 22 13:39:51 rhel5 nmbd18445: Samba name server RHEL5 is now a local master browser for workgroup MYGROUP on subnet 88 Mar 22 13:39:51 rhel5 nmbd18445: Mar 22 13:39:51 rhel5 nmbd18445: * Mar 22 16:17:20 rhel5 nmbd18445: 2009/03/22 16:17:20, 0 nmbd/nmbd.c:terminate(58) Mar 22 16:17:20 rhel5 nmbd18445: Got SIGTERM: going down. Mar 22 16:22:51 rhel5 nmbd23030: 2009/03/22 16:22:51, 0 nmbd/nmbd_become_lmb.c:become_local_master_stage2(396) Mar 22 16:22:51 rhel5 nmbd23030: * Mar 22 16:22:51 rhel5 nmbd23030: Mar 22 16:22:51 rhel5 nmbd23030: Samba name server RHEL5 is now a local master browser for workgroup MYGROUP on subnet 88 Mar 22 16:22:51 rhel5 nmbd23030: Mar 22 16:22:51 rhel5 nmbd23030: * Mar 22 16:28:33 rhel5 nmbd23030: 2009/03/22 16:28:33, 0 nmbd/nmbd.c:terminate(58) Mar 22 16:28:33 rhel5 nmbd23030: Got SIGTERM: going down. Mar 22 16:34:15 rhel5 nmbd23366: 2009/03/22 16:34:15, 0 nmbd/nmbd_become_lmb.c:become_local_master_stage2(396) Mar 22 16:34:15 rhel5 nmbd23366: * Mar 22 16:34:15 rhel5 nmbd23366: Mar 22 16:34:15 rhel5 nmbd23366: Samba name server RHEL5 is now a local master browser for workgroup MYGROUP on subnet 88 Mar 22 16:34:15 rhel5 nmbd23366: Mar 22 16:34:15 rhel5 nmbd23366: * Mar 23 10:44:21 rhel5 kernel: VFS: busy inodes on changed media. Mar 23 10:44:26 rhel5 last message repeated 7 times Mar 23 14:01:09 rhel5 dhcpd: WARNING: Host declarations are global. They are not limited to the scope you declared them in. Mar 23 14:01:10 rhel5 dhcpd: dhcpd shutdown succeeded Mar 23 14:01:10 rhel5 dhcpd: Internet Systems Consortium DHCP Server V3.0.5-RedHat Mar 23 14:01:10 rhel5 dhcpd: Copyright 2004-2006 Internet Systems Consortium. Mar 23 14:01:10 rhel5 dhcpd: All rights reserved. Mar 23 14:01:10 rhel5 dhcpd: For info, please visit url/sw/dhcp/url Mar 23 14:01:10 rhel5 dhcpd: WARNING: Host declarations are global. They are not limited to the scope you declared them in. Mar 23 14:01:10 rhel5 dhcpd: Wrote 0 deleted host decls to leases file. Mar 23 14:01:10 rhel5 dhcpd: Wrote 0 new dynamic host decls to leases file. Mar 23 14:01:10 rhel5 dhcpd: Wrote 0 leases to leases file. Mar 23 14:01:10 rhel5 dhcpd: Listening on LPF/eth0/00:0c:29:ec:fd:83/192.168.0/24 Mar 23 14:01:11 rhel5 dhcpd: Sending on LPF/eth0/00:0c:29:ec:fd:83/192.168.0/24 Mar 23 14:01:11 rhel5 dhcpd: Se