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<p class="MsoNormal"><span style="font-family: 'WenQuanYi Micro Hei'"><span style="background-color: rgb(255, 255, 255); "><span lang="EN-US"> </span><span lang="EN-US">DNS</span>服务器介绍</span></span>
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<p class="MsoNormal"><span style="font-family: 'WenQuanYi Micro Hei'"><span style="background-color: rgb(255, 255, 255); "><br /></span></span>
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<p class="MsoNormal"><span style="font-family: 'WenQuanYi Micro Hei'"><span style="background-color: rgb(255, 255, 255); "><span lang="EN-US"> 一、</span><span lang="EN-US">DNS</span>服务器介绍</span></span>
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<p class="MsoNormal"><span style="font-family: 'WenQuanYi Micro Hei'"><span lang="EN-US">1.DNS</span>服务器:<span style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; "> <span lang="EN-US">DNS</span></span><span style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">(</span><span lang="EN-US" style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">Domain Name Server</span><span style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">,域名服务器)是进行域名</span><span lang="EN-US" style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">(domain name)</span><span style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">和与之相对应的</span><span lang="EN-US" style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">IP</span><span style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">地址</span><span lang="EN-US" style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; "> (IP address)</span><span style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">转换的服务器。</span><span lang="EN-US" style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">DNS</span><span style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">中保存了一张域名和与之相对应的</span><span lang="EN-US" style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">IP</span><span style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">地址</span><span lang="EN-US" style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; "> (IP address)</span><span style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">的表,</span><span lang="EN-US" style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">DNS</span><span style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">的作用用来</span>网络域名解析服务,使用浏览器访问网页就需要使用<span lang="EN-US">ISP</span>的<span lang="EN-US">DNS</span>服务器,如果你想访问的域名在本地<span lang="EN-US">DNS</span>未解析成功,本地<span lang="EN-US">DNS</span>会将该域名转发给<span lang="EN-US" style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">13</span><span style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">台根<span lang="EN-US">DNS</span>解析(主根服务在美国,亚洲有一台辅根服务器在日本),所有根服务器都保存有各地当前注册的域名信息,如果<span lang="EN-US">13</span>根服务器也未解析成功,说明这是一个未注册的域名,网页显示失败</span><span lang="EN-US"><o:p></o:p></span></span>
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<p class="MsoNormal"><span style="font-family: 'WenQuanYi Micro Hei'"><span lang="EN-US" style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; "><o:p> </o:p></span></span>
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<p class="MsoNormal"><span style="font-family: 'WenQuanYi Micro Hei'">二、DNS分类</span>
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<p class="MsoNormal"><span style="font-family: 'WenQuanYi Micro Hei'"><span lang="EN-US">1. </span>网络运行商<span lang="EN-US">DNS</span>服务器功能保存有本地注册的域名信息及连接<span lang="EN-US">13</span>根服务器<span lang="EN-US"><span style="mso-spacerun:yes"> </span><o:p></o:p></span></span>
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<p class="MsoNormal"><span style="font-family: 'WenQuanYi Micro Hei'"><span lang="EN-US"><o:p> </o:p></span></span>
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<p class="MsoNormal"><span style="font-family: 'WenQuanYi Micro Hei'"><span lang="EN-US">2. </span>企业内网<span lang="EN-US">DNS</span>服务器功能<span lang="EN-US"><o:p></o:p></span></span>
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<p class="MsoNormal"><span style="font-family: 'WenQuanYi Micro Hei'">企业内部主机多,<span style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">域名解析需求多,如果都使用本地<span lang="EN-US">dns</span>域名解析,都向本地<span lang="EN-US">DNS</span>发数据包,必然会消耗掉企业到互联网之间宝贵的带宽,所以很有必要在内网中搭建<span lang="EN-US">DNS</span>,将外网解析工作交由内网<span lang="EN-US">DNS</span>服务器完成,对于外网的域名,只需要内网<span lang="EN-US">DNS</span>服务器解析缓存一次即可,<span lang="EN-US"><o:p></o:p></span></span></span>
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<p class="MsoNormal"><span style="font-family: 'WenQuanYi Micro Hei'; ">如此就可以节约大量的网络带宽,<span style="background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: white; ">内网使用<span lang="