内外网DNS分流解决方案-陌上烟雨遥

一般公司内部都会有内部 DNS 服务器，由于托管公司内网域名，且会当成公司内部上网的专用 DNS，同时承载外网的域名解析工作。但是有时候公司内网的 DNS 服务不稳定时，就比较尴尬，不用吧，解析不了内网域名，用吧，上不了外网。这时候用 DNS 的分流工具就是解决这个问题的好办法。这篇文章会拿 win10 举例，讲解 coredns 的简单配置，来解决 DNS 分流问题。

首先下载 coredns 安装包 https://github.com/coredns/coredns/releases/latest 将其解压到本地磁盘

图 1.1

这里解压到的是 D:\program2\coredns_1.8.6_windows_amd64\ 这个目录。然后在这个目录中编写 coredns 的配置文件


(inner) { errors # 禁用ipv6解析 rewrite stop type AAAA A cache 3 forward . 内网DNS服务的IP reload log } 17zuoye.net { import inner } . { any errors health { lameduck 5s } ready forward . 119.29.29.29 223.5.5.5 cache 30 reload log }<span aria-hidden="true" class="line-numbers-rows"><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span></span>
(inner) { errors # 禁用ipv6解析 rewrite stop type AAAA A cache 3 forward . 内网DNS服务的IP reload log } 17zuoye.net { import inner } . { any errors health { lameduck 5s } ready forward . 119.29.29.29 223.5.5.5 cache 30 reload log }<span aria-hidden="true" class="line-numbers-rows"><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span></span>
(inner) { errors # 禁用ipv6解析 rewrite stop type AAAA A cache 3 forward . 内网DNS服务的IP reload log } 17zuoye.net { import inner } . { any errors health { lameduck 5s } ready forward . 119.29.29.29 223.5.5.5 cache 30 reload log }

为了保证 coredns 能够在windows中开机自启动，还要借助 winsw 这个工具，从 https://github.com/winsw/winsw/releases 中下载最新版本，其中 win10 对应的二进制文件 WinSW.NET461.exe。将 winsw 的二进制文件拷贝到刚才的工作目录，然后重命名为 coredns-service.exe 。

接着在刚才的工作目录中创建 coredns-service.xml，输入以下内容


<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>service</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>id</span><span class="token punctuation">></span></span>CoreDNS<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>id</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>name</span><span class="token punctuation">></span></span>CoreDNS Service (powered by WinSW)<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>name</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>description</span><span class="token punctuation">></span></span>This service is a CoreDNS service<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>description</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>executable</span><span class="token punctuation">></span></span>D:\program2\coredns_1.8.6_windows_amd64\coredns.exe<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>executable</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>workingdirectory</span><span class="token punctuation">></span></span>D:\program2\coredns_1.8.6_windows_amd64\<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>workingdirectory</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>onfailure</span> <span class="token attr-name">action</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>restart<span class="token punctuation">"</span></span> <span class="token attr-name">delay</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>10 sec<span class="token punctuation">"</span></span><span class="token punctuation">/></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>startmode</span><span class="token punctuation">></span></span>Automatic<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>startmode</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>log</span> <span class="token attr-name">mode</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>reset<span class="token punctuation">"</span></span><span class="token punctuation">/></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>service</span><span class="token punctuation">></span></span><span aria-hidden="true" class="line-numbers-rows"><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>service</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>id</span><span class="token punctuation">></span></span>CoreDNS<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>id</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>name</span><span class="token punctuation">></span></span>CoreDNS Service (powered by WinSW)<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>name</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>description</span><span class="token punctuation">></span></span>This service is a CoreDNS service<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>description</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>executable</span><span class="token punctuation">></span></span>D:\program2\coredns_1.8.6_windows_amd64\coredns.exe<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>executable</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>workingdirectory</span><span class="token punctuation">></span></span>D:\program2\coredns_1.8.6_windows_amd64\<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>workingdirectory</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>onfailure</span> <span class="token attr-name">action</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>restart<span class="token punctuation">"</span></span> <span class="token attr-name">delay</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>10 sec<span class="token punctuation">"</span></span><span class="token punctuation">/></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>startmode</span><span class="token punctuation">></span></span>Automatic<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>startmode</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>log</span> <span class="token attr-name">mode</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>reset<span class="token punctuation">"</span></span><span class="token punctuation">/></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>service</span><span class="token punctuation">></span></span><span aria-hidden="true" class="line-numbers-rows"><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span><span></span></span>
<service> <id>CoreDNS</id> <name>CoreDNS Service (powered by WinSW)</name> <description>This service is a CoreDNS service</description> <executable>D:\program2\coredns_1.8.6_windows_amd64\coredns.exe</executable> <workingdirectory>D:\program2\coredns_1.8.6_windows_amd64\</workingdirectory> <onfailure action="restart" delay="10 sec"/> <startmode>Automatic</startmode> <log mode="reset"/> </service>

通过命令 D:\program2\coredns_1.8.6_windows_amd64\coredns-service.exe install 可以在 windows 中将 coredns 安装为系统服务，通过命令 D:\program2\coredns_1.8.6_windows_amd64\coredns-service.exe start 可以在后台启动这个系统服务。上面两个命令只需要在初始化安装的时候执行一次即可，下次开机的时候，就能自动启动 coredns 了，不过需要注意的是运行需要的超管权限。通过命令 D:\program2\coredns_1.8.6_windows_amd64\coredns-service.exe status 可以查看服务状态。

通过命令 nslookup www.baidu.com 127.0.0.1 ，如果返回如下内容


服务器: localhost Address: 127.0.0.1 非权威应答: 名称: www.a.shifen.com Addresses: 163.177.151.109 163.177.151.110 Aliases: www.baidu.com<span aria-hidden="true" class="line-numbers-rows"><span></span><span></span><span></span><span></span><span></span><span></span><span></span></span>
服务器: localhost Address: 127.0.0.1 非权威应答: 名称: www.a.shifen.com Addresses: 163.177.151.109 163.177.151.110 Aliases: www.baidu.com<span aria-hidden="true" class="line-numbers-rows"><span></span><span></span><span></span><span></span><span></span><span></span><span></span></span>
服务器: localhost Address: 127.0.0.1 非权威应答: 名称: www.a.shifen.com Addresses: 163.177.151.109 163.177.151.110 Aliases: www.baidu.com