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<?xml version="1.0" encoding="UTF-8"?><rss xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:content="http://purl.org/rss/1.0/modules/content/" xmlns:atom="http://www.w3.org/2005/Atom" version="2.0"><channel><title><![CDATA[Mingxin's Blog RSS Feed]]></title><description><![CDATA[A personal website of Mingxin]]></description><link>https://mingxinwei.github.io</link><generator>GatsbyJS</generator><lastBuildDate>Mon, 11 May 2026 14:44:14 GMT</lastBuildDate><item><title><![CDATA[一次http debug经历]]></title><description><![CDATA[最近有同事反馈，调用服务A的内部接口会偶现超时错误。于是开始查出错的原因。 首先了解了具体情况，调用方的设置的超时时间是2s；错误是偶发的；超时之后重试一般都会成功。 再往服务里加了一些debug日志，最后查出来是这个服务A调用另一个服务B…]]></description><link>https://mingxinwei.github.io/An HTTP Debug Experience/</link><guid isPermaLink="false">https://mingxinwei.github.io/An HTTP Debug Experience/</guid><pubDate>Fri, 22 May 2020 18:20:31 GMT</pubDate><content:encoded>&lt;p&gt;最近有同事反馈，调用服务A的内部接口会偶现超时错误。于是开始查出错的原因。&lt;/p&gt;
&lt;p&gt;首先了解了具体情况，调用方的设置的超时时间是2s；错误是偶发的；超时之后重试一般都会成功。&lt;/p&gt;
&lt;p&gt;再往服务里加了一些debug日志，最后查出来是这个服务A调用另一个服务B的时候会超时。这个调用设置的超时时间是5s，所以这个请求超时之前，那边2s的请求就已经先报超时错误了。这是错误的表象，深层的原因还需要去服务B里查看。&lt;/p&gt;
&lt;p&gt;在服务B里查看对应的日志，发现这些超时的请求都会报出一个&lt;code class=&quot;language-text&quot;&gt;Error: Parse Error&lt;/code&gt;:&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;text&quot;&gt;&lt;pre class=&quot;language-text&quot;&gt;&lt;code class=&quot;language-text&quot;&gt;Error: Parse Error
at socketOnEnd (_http_server.js:455:20)
at Socket.emit (events.js:203:15)
at Socket.EventEmitter.emit (domain.js:448:20)
at endReadableNT (_stream_readable.js:1129:12)
at process._tickCallback (internal/process/next_tick.js:63:19)&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;查看对应的代码&lt;a href=&quot;https://github.com/nodejs/node/blob/v10.16.0/lib/_http_server.js#L455-L461&quot;&gt;_http_server.js&lt;/a&gt;，这个错误是由client超时关闭socket，server在处理socket end事件时释放HTTP parser出错导致的。&lt;/p&gt;
&lt;p&gt;这说明HTTP请求的解析失败，可能是server收到了一个错误格式的HTTP请求。不过这里我有了另一个疑问，server在一个无法解析的HTTP请求上为什么没有马上报错，而是hang up直到5s之后超时？&lt;/p&gt;
&lt;p&gt;所以怀疑是A服务的HTTP请求库 &lt;a href=&quot;https://github.com/request/request&quot;&gt;request&lt;/a&gt;会偶尔发送一个错误格式的HTTP请求过去。在github找到一个可能相关的request的&lt;a href=&quot;https://github.com/request/request/issues/2047&quot;&gt;issue&lt;/a&gt;，尤其是里面有一个&lt;a href=&quot;https://github.com/request/request/issues/2047#issuecomment-471077041&quot;&gt;comment&lt;/a&gt;和我遇到的现象很相似。不过这些都是猜测，要证明是request的问题，还是需要找到一个错误格式的HTTP请求的例子。&lt;/p&gt;
&lt;p&gt;因为server在接受到HTTP请求的时候无法解析hang up了，不能在HTTP协议这一层去获取到数据。所以尝试在TCP层去输出数据。多亏Node.js是事件驱动的特性，输出socket的数据只需要在socket上增加一个data事件的listener:&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;js&quot;&gt;&lt;pre class=&quot;language-js&quot;&gt;&lt;code class=&quot;language-js&quot;&gt;&lt;span class=&quot;token keyword&quot;&gt;const&lt;/span&gt; Koa &lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;token function&quot;&gt;require&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token string&quot;&gt;&apos;koa&apos;&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;
&lt;span class=&quot;token keyword&quot;&gt;const&lt;/span&gt; app &lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;token keyword&quot;&gt;new&lt;/span&gt; &lt;span class=&quot;token class-name&quot;&gt;Koa&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;

&lt;span class=&quot;token keyword&quot;&gt;const&lt;/span&gt; server &lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; http&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;createServer&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;app&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;callback&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;listen&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;config&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;get&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token string&quot;&gt;&apos;port&apos;&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;

server&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;on&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token string&quot;&gt;&apos;connection&apos;&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;token parameter&quot;&gt;socket&lt;/span&gt; &lt;span class=&quot;token operator&quot;&gt;=&gt;&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;{&lt;/span&gt;
  socket&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;on&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token string&quot;&gt;&apos;data&apos;&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;token parameter&quot;&gt;d&lt;/span&gt; &lt;span class=&quot;token operator&quot;&gt;=&gt;&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;{&lt;/span&gt;
    console&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;log&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token string&quot;&gt;&apos;%d socket data: %s&apos;&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;,&lt;/span&gt; Date&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;now&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;token constant&quot;&gt;JSON&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;stringify&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;d&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;toString&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt; &lt;span class=&quot;token comment&quot;&gt;// stringify是为了输出日志到一行&lt;/span&gt;
  &lt;span class=&quot;token punctuation&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;
&lt;span class=&quot;token punctuation&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;注：测试时发现这种做法会与koa-morgan middleware冲突，会让之后的handler无法读取到body。所以如果使用了morgan需要暂时禁用。&lt;/p&gt;
&lt;p&gt;加了日志之后觉得终于可以抓到错误格式的请求了，没想到这个bug就玩消失了-_-（可能是具有量子力学不可观测性的bug）。一周之后终于找到几个日志，错误的http请求是长这样的：&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;text&quot;&gt;&lt;pre class=&quot;language-text&quot;&gt;&lt;code class=&quot;language-text&quot;&gt;POST /list HTTP/1.1\r\ncontent-type: application/json\r\naccept-encoding: gzip, deflate\r\naccept: application/json\r\ncontent-length: 117\r\nConnection: close\r\n\r\n
&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;这个请求应该传递117字节的数据，但是却没有传对应的body，所以解析失败。&lt;/p&gt;
&lt;p&gt;这也解释了为什么server为什么会hang up到超时，因为header里指定了content-length，但是却没有传对应的body，server认为还有数据没有传过来，于是一直在等待后续的数据。在client超时关闭连接后，server的HTTP parser就报错了。&lt;/p&gt;
&lt;p&gt;由于request&lt;a href=&quot;https://github.com/request/request#deprecated&quot;&gt;已经不在维护&lt;/a&gt;，最后换用了&lt;a href=&quot;https://github.com/sindresorhus/got&quot;&gt;got&lt;/a&gt;来解决这个问题。&lt;/p&gt;</content:encoded></item><item><title><![CDATA[VXLAN & Flannel]]></title><description><![CDATA[VXLAN 是什么 Virtual Extensible LAN(VXLAN)是一个在三层网络上模拟二层网络的网络虚拟化技术。可以解决云计算场景下子网不够用的问题。 有一个和 VXLAN 名字和解决的问题都很相似的技术：VLAN，VXLAN 和 VLAN…]]></description><link>https://mingxinwei.github.io/VXLAN&amp;Flannel/</link><guid isPermaLink="false">https://mingxinwei.github.io/VXLAN&amp;Flannel/</guid><pubDate>Mon, 23 Dec 2019 11:51:30 GMT</pubDate><content:encoded>&lt;h3&gt;VXLAN 是什么&lt;/h3&gt;
&lt;p&gt;Virtual Extensible LAN(VXLAN)是一个在三层网络上模拟二层网络的网络虚拟化技术。可以解决云计算场景下子网不够用的问题。&lt;/p&gt;
&lt;p&gt;有一个和 VXLAN 名字和解决的问题都很相似的技术：VLAN，VXLAN 和 VLAN 相比的优点是什么？&lt;/p&gt;
&lt;p&gt;传统 VLAN 只能支持 4000 个子网，VXLAN 可以支持 1600 万个子网。&lt;/p&gt;
&lt;h3&gt;VXLAN 原理&lt;/h3&gt;
&lt;p&gt;使用三层网络的 udp 包来封装二层的数据包。..&lt;/p&gt;
&lt;h4&gt;包结构&lt;/h4&gt;
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&lt;p&gt;（图片来源：&lt;a href=&quot;https://cizixs.com/2017/09/25/vxlan-protocol-introduction/&quot;&gt;vxlan 协议原理简介&lt;/a&gt;）&lt;/p&gt;
&lt;p&gt;从最内层往外看：最内层的 Original L2 Frame 是虚拟子网的二层数据包，在前面加上 VXLAN 的 header。之后就被当作一个普通的 udp 包的 payload，在真正的物理子网上发送出去。&lt;/p&gt;
&lt;p&gt;这里可以注意一下 VXLAN Header 中的 VNID 字段，共占 24bit，所以 VXLAN 能够支持的不同子网共有&lt;code class=&quot;language-text&quot;&gt;2^24 = 16777216&lt;/code&gt;个。&lt;/p&gt;
&lt;h4&gt;组网原理&lt;/h4&gt;
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&lt;p&gt;（图片来源：&lt;a href=&quot;https://cizixs.com/2017/09/25/vxlan-protocol-introduction/&quot;&gt;vxlan 协议原理简介&lt;/a&gt;）&lt;/p&gt;
&lt;p&gt;一个 VXLAN 网络中有几个重要的部分：&lt;/p&gt;
&lt;ol&gt;
&lt;li&gt;VTEP，VXLAN Tunnel Endpoint。这个是每个机器上都会有一个 VXLAN 网络的 endpoint，负责对数据包进行封包和解包。可以是软件实现，也可以是专有的硬件。&lt;/li&gt;
&lt;li&gt;VNI，区分不同 VXLAN 网络的标识符，这个主要是设置在每个 VTEP 上，VNI 相同的 VTEP 在一个子网里。&lt;/li&gt;
&lt;/ol&gt;
&lt;p&gt;几台机器想要组成一个 VXLAN，需要哪些信息？换句话说，假设已经有了一个 VXLAN 网络，在这个网络内的机器 A 想要给机器 B 发个数据包，有哪些地址字段需要填写？&lt;/p&gt;
&lt;p&gt;需要填写的字段有 4 个：&lt;/p&gt;
&lt;ol&gt;
&lt;li&gt;内层（虚拟子网）的 IP 地址&lt;/li&gt;
&lt;li&gt;内层的 MAC 地址&lt;/li&gt;
&lt;li&gt;外层（物理子网）的 IP 地址&lt;/li&gt;
&lt;li&gt;外层的 MAC 地址&lt;/li&gt;
&lt;/ol&gt;
&lt;p&gt;A 上的应用要给 B 发消息，肯定是知道 B 的 IP 地址（内层 IP 地址）；并且如果知道外层的 IP 地址，通过物理子网的 arp 可以知道外层的 MAC。所以还缺少的地址有：&lt;/p&gt;
&lt;ol&gt;
&lt;li&gt;内层（虚拟子网）的 MAC 地址&lt;/li&gt;
&lt;li&gt;外层（物理子网）的 IP 地址&lt;/li&gt;
&lt;/ol&gt;
&lt;p&gt;想要得到这两个信息，一般有组播和控制中心两种办法。&lt;/p&gt;
&lt;ol&gt;
&lt;li&gt;组播是通过在组播地址上组播，VTEP 自动学习着两个信息。这里先不展开介绍&lt;/li&gt;
&lt;li&gt;控制中心是通过一个中心数据库来提供这两个信息，比如在 k8s 中可以在创建 pod 的时候，把 1. pod 的 MAC 地址 2. pod 所在机器的 IP 地址存储到 etcd 里，在后面别的机器（上的 pod）需要和这个 pod 通信的时候，可以通过像 etcd 发起查询得到这两个信息，就可以通信了。&lt;/li&gt;
&lt;/ol&gt;
&lt;h3&gt;在 linux 中实践 VXLAN&lt;/h3&gt;
&lt;h4&gt;目标&lt;/h4&gt;
&lt;p&gt;在 2 台机器上构建一个 VXLAN，使机器&amp;#x3C;==&gt;机器，机器&amp;#x3C;==&gt;容器，容器&amp;#x3C;==&gt;容器之间都可以通信。&lt;/p&gt;
&lt;h4&gt;网络拓扑&lt;/h4&gt;
&lt;p&gt;&lt;span
      class=&quot;gatsby-resp-image-wrapper&quot;
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        src=&quot;/static/12be2088c186b3768405cb0713bbedc6/fcda8/expected-network-topography-vxlan.png&quot;
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&lt;p&gt;（图片来源: &lt;a href=&quot;https://github.com/yangyuqian/k8s-the-hard-way/blob/master/network/vxlan-flannel-cn.md&quot;&gt;VXLAN 在 Flannel 中的 Overlay 网络的实现&lt;/a&gt;）&lt;/p&gt;
&lt;p&gt;需要搭建的 overlay 子网为 192.1.0.0/16。&lt;/p&gt;
&lt;h4&gt;步骤&lt;/h4&gt;
&lt;ol&gt;
&lt;li&gt;创建 VXLAN interface（VTEP），给 VXLAN 分配 ip&lt;/li&gt;
&lt;li&gt;路由表新增一项，把虚拟子网的流量交给 VTEP 处理&lt;/li&gt;
&lt;li&gt;上面提到要打包缺少的地址：「内层（虚拟子网）的 MAC 地址」，这里通过手动修改 ARP 表实现。ARP 表新增几项，把 overlay 网络上需要访问的容器（机器）ip 地址都指向&lt;strong&gt;该机器的 VTEP 的 MAC 地址&lt;/strong&gt;。&lt;/li&gt;
&lt;li&gt;另一个缺少的地址：「外层（物理子网）的 IP 地址」，通过修改转发表来实现。转发表新增一项，把发往 VTEP MAC 地址的流量都指向另一台机器的物理子网 ip&lt;/li&gt;
&lt;/ol&gt;
&lt;h4&gt;一个数据包的奥德赛&lt;/h4&gt;
&lt;p&gt;经过这样的配置之后，一个数据包怎么从一个机器/容器路由到另一个机器/容器呢？这里选择讲解一个最长的路由路径：容器&amp;#x3C;==&gt;容器，其他情况都包含在这个路径里。
假设 node1 上的容器 A 192.1.78.2 想要发一个数据包给 node2 上的容器 B 192.1.87.2&lt;/p&gt;
&lt;ol&gt;
&lt;li&gt;
&lt;p&gt;数据包从 A 发出，通过 docker bridge 来到 docker0 interface，docker0 需要知道该把这个数据包发给谁，于是他查询了路由表，发现命中了这条规则&lt;code class=&quot;language-text&quot;&gt;192.1.0.0/16&lt;/code&gt;，于是发往 vxlan.1 interface。&lt;/p&gt;
&lt;/li&gt;
&lt;li&gt;
&lt;p&gt;vxlan.1 收到数据包之后开始打包，需要填写 4 个地址：&lt;/p&gt;
&lt;blockquote&gt;
&lt;ol&gt;
&lt;li&gt;内层（虚拟子网）的 IP 地址&lt;/li&gt;
&lt;li&gt;内层的 MAC 地址&lt;/li&gt;
&lt;li&gt;外层（物理子网）的 IP 地址&lt;/li&gt;
&lt;li&gt;外层的 MAC 地址&lt;/li&gt;
&lt;/ol&gt;
&lt;/blockquote&gt;
&lt;/li&gt;
&lt;/ol&gt;
&lt;p&gt;1 已知；2 会通过 arp 请求去查找，命中前面手动维护的本地 arp 缓存，得到 node2 VTEP 的 MAC 地址；3 会命中手动维护的 fdb 转发表，得到 node2 的物理子网 IP 地址；4 通过物理子网 arp 得到。&lt;/p&gt;
&lt;ol start=&quot;3&quot;&gt;
&lt;li&gt;
&lt;p&gt;打包完成后，得到一个物理子网的普通 udp 包发往 node2 的 4789 端口。node2 的 vxlan.1 interface 监听该端口，接到 udp 包之后解开封装得到内层的数据包。&lt;/p&gt;
&lt;/li&gt;
&lt;li&gt;
&lt;p&gt;vxlan.1 需要知道数据包该发往哪里，同样查询本机的路由表，命中&lt;code class=&quot;language-text&quot;&gt;192.1.87.0/24&lt;/code&gt;，发往 docker0 interface。docker0 再将数据包发给容器 B。&lt;/p&gt;
&lt;/li&gt;
&lt;/ol&gt;
&lt;h4&gt;实践&lt;/h4&gt;
&lt;h5&gt;1. 实现机器&amp;#x3C;==&gt;机器通信&lt;/h5&gt;
&lt;p&gt;将以上步骤写到一起，方便执行：&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;bash&quot;&gt;&lt;pre class=&quot;language-bash&quot;&gt;&lt;code class=&quot;language-bash&quot;&gt;&lt;span class=&quot;token comment&quot;&gt;# step1&lt;/span&gt;
&lt;span class=&quot;token builtin class-name&quot;&gt;export&lt;/span&gt; &lt;span class=&quot;token assign-left variable&quot;&gt;IP&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;token comment&quot;&gt;# 本机ip&lt;/span&gt;
&lt;span class=&quot;token builtin class-name&quot;&gt;export&lt;/span&gt; &lt;span class=&quot;token assign-left variable&quot;&gt;DEST_IP&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;token comment&quot;&gt;# 另一台机器ip&lt;/span&gt;
&lt;span class=&quot;token builtin class-name&quot;&gt;export&lt;/span&gt; &lt;span class=&quot;token assign-left variable&quot;&gt;VTEP_IP&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;token comment&quot;&gt;# 本机VTEP ip&lt;/span&gt;
&lt;span class=&quot;token builtin class-name&quot;&gt;export&lt;/span&gt; &lt;span class=&quot;token assign-left variable&quot;&gt;PREFIX&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt;vxlan
&lt;span class=&quot;token builtin class-name&quot;&gt;export&lt;/span&gt; &lt;span class=&quot;token assign-left variable&quot;&gt;PORT&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;token number&quot;&gt;4789&lt;/span&gt;
&lt;span class=&quot;token builtin class-name&quot;&gt;export&lt;/span&gt; &lt;span class=&quot;token assign-left variable&quot;&gt;VNI&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;token number&quot;&gt;1&lt;/span&gt;
&lt;span class=&quot;token builtin class-name&quot;&gt;export&lt;/span&gt; &lt;span class=&quot;token assign-left variable&quot;&gt;SUBNET&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;token number&quot;&gt;192&lt;/span&gt;.&lt;span class=&quot;token variable&quot;&gt;$VNI&lt;/span&gt;.0.0/16
&lt;span class=&quot;token builtin class-name&quot;&gt;export&lt;/span&gt; &lt;span class=&quot;token assign-left variable&quot;&gt;DEVICE_NAME&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;token variable&quot;&gt;$PREFIX&lt;/span&gt;&lt;span class=&quot;token builtin class-name&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token variable&quot;&gt;$VNI&lt;/span&gt;

&lt;span class=&quot;token function&quot;&gt;ip&lt;/span&gt; &lt;span class=&quot;token function&quot;&gt;link&lt;/span&gt; &lt;span class=&quot;token function&quot;&gt;add&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$DEVICE_NAME&lt;/span&gt; &lt;span class=&quot;token builtin class-name&quot;&gt;type&lt;/span&gt; vxlan &lt;span class=&quot;token function&quot;&gt;id&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$VNI&lt;/span&gt; dev eth0 dstport &lt;span class=&quot;token variable&quot;&gt;$PORT&lt;/span&gt; nolearning
&lt;span class=&quot;token function&quot;&gt;ip&lt;/span&gt; address &lt;span class=&quot;token function&quot;&gt;add&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$VTEP_IP&lt;/span&gt; dev &lt;span class=&quot;token variable&quot;&gt;$DEVICE_NAME&lt;/span&gt;
&lt;span class=&quot;token function&quot;&gt;ip&lt;/span&gt; &lt;span class=&quot;token function&quot;&gt;link&lt;/span&gt; &lt;span class=&quot;token builtin class-name&quot;&gt;set&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$DEVICE_NAME&lt;/span&gt; up
&lt;span class=&quot;token function&quot;&gt;ip&lt;/span&gt; route &lt;span class=&quot;token function&quot;&gt;add&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$SUBNET&lt;/span&gt; dev &lt;span class=&quot;token variable&quot;&gt;$DEVICE_NAME&lt;/span&gt; scope global

&lt;span class=&quot;token comment&quot;&gt;# step2 需要拿到step1的结果后在再进行&lt;/span&gt;
&lt;span class=&quot;token builtin class-name&quot;&gt;export&lt;/span&gt; &lt;span class=&quot;token assign-left variable&quot;&gt;ANOTHER_VTEP_MAC&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;token comment&quot;&gt;# 需要等另一台机器的VXLAN设备创建之后，查看其MAC地址&lt;/span&gt;
bridge fdb &lt;span class=&quot;token function&quot;&gt;add&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$ANOTHER_VTEP_MAC&lt;/span&gt; dev &lt;span class=&quot;token variable&quot;&gt;$DEVICE_NAME&lt;/span&gt; dst &lt;span class=&quot;token variable&quot;&gt;$DEST_IP&lt;/span&gt;

&lt;span class=&quot;token builtin class-name&quot;&gt;export&lt;/span&gt; &lt;span class=&quot;token assign-left variable&quot;&gt;ANOTHER_NODE_IP&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;token comment&quot;&gt;# 需要访问的另一台机器上的（容器或机器）ip&lt;/span&gt;
&lt;span class=&quot;token function&quot;&gt;ip&lt;/span&gt; neighbor &lt;span class=&quot;token function&quot;&gt;add&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$ANOTHER_NODE_IP&lt;/span&gt; lladdr &lt;span class=&quot;token variable&quot;&gt;$ANOTHER_VTEP_MAC&lt;/span&gt; dev &lt;span class=&quot;token variable&quot;&gt;$DEVICE_NAME&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;Node1:&lt;/p&gt;
&lt;p&gt;&lt;span
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    &lt;/span&gt;&lt;/p&gt;
&lt;p&gt;Node2 :&lt;/p&gt;
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        style=&quot;width:100%;height:100%;margin:0;vertical-align:middle;position:absolute;top:0;left:0;&quot;
        loading=&quot;lazy&quot;
        decoding=&quot;async&quot;
      /&gt;
  &lt;/a&gt;
    &lt;/span&gt;&lt;/p&gt;
&lt;p&gt;查看一下这样执行之后机器上的路由表、arp 表、和 fdb 转发表的内容，这里以 node1 为例：&lt;/p&gt;
&lt;p&gt;路由表：&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;bash&quot;&gt;&lt;pre class=&quot;language-bash&quot;&gt;&lt;code class=&quot;language-bash&quot;&gt;root@VM-0-7-ubuntu:~&lt;span class=&quot;token comment&quot;&gt;# ip route&lt;/span&gt;
default via &lt;span class=&quot;token number&quot;&gt;172.17&lt;/span&gt;.0.1 dev eth0 proto static
&lt;span class=&quot;token number&quot;&gt;172.17&lt;/span&gt;.0.0/20 dev eth0 proto kernel scope &lt;span class=&quot;token function&quot;&gt;link&lt;/span&gt; src &lt;span class=&quot;token number&quot;&gt;172.17&lt;/span&gt;.0.7
&lt;span class=&quot;token number&quot;&gt;172.18&lt;/span&gt;.0.0/16 dev docker0 proto kernel scope &lt;span class=&quot;token function&quot;&gt;link&lt;/span&gt; src &lt;span class=&quot;token number&quot;&gt;172.18&lt;/span&gt;.0.1 linkdown
&lt;span class=&quot;token number&quot;&gt;192.1&lt;/span&gt;.0.0/16 dev vxlan.1&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;&lt;code class=&quot;language-text&quot;&gt;192.1.0.0/16 dev vxlan.1&lt;/code&gt;这条规则指定了&lt;code class=&quot;language-text&quot;&gt;192.1.0.0/16&lt;/code&gt;这个子网的流量都会通过&lt;code class=&quot;language-text&quot;&gt;vxlan.1&lt;/code&gt;这个设备来处理。&lt;/p&gt;
&lt;p&gt;arp 表：&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;bash&quot;&gt;&lt;pre class=&quot;language-bash&quot;&gt;&lt;code class=&quot;language-bash&quot;&gt;root@VM-0-7-ubuntu:~&lt;span class=&quot;token comment&quot;&gt;# ip neighbor&lt;/span&gt;
&lt;span class=&quot;token number&quot;&gt;192.1&lt;/span&gt;.87.0 dev vxlan.1 lladdr d2:04:98:13:a7:aa PERMANENT
&lt;span class=&quot;token number&quot;&gt;172.17&lt;/span&gt;.0.1 dev eth0 lladdr fe:ee:00:2e:16:9a REACHABLE
&lt;span class=&quot;token number&quot;&gt;172.17&lt;/span&gt;.0.4 dev eth0 lladdr fe:ee:00:2e:16:9a STALE&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;在 arp 表中添加了我们需要访问的 ip &lt;code class=&quot;language-text&quot;&gt;192.1.87.0&lt;/code&gt;的 MAC 地址（因为我们需要 ping 的 node2 的机器 ip）。需要注意的是，如果等下需要访问 node2 容器的 ip 地址（比如&lt;code class=&quot;language-text&quot;&gt;192.1.87.2&lt;/code&gt;)，这里还需要添加一条记录。&lt;/p&gt;
&lt;p&gt;fdb 转发表：&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;bash&quot;&gt;&lt;pre class=&quot;language-bash&quot;&gt;&lt;code class=&quot;language-bash&quot;&gt;root@VM-0-7-ubuntu:~&lt;span class=&quot;token comment&quot;&gt;# bridge fdb&lt;/span&gt;
&lt;span class=&quot;token number&quot;&gt;33&lt;/span&gt;:33:00:00:00:01 dev eth0 self permanent
01:00:5e:00:00:01 dev eth0 self permanent
&lt;span class=&quot;token number&quot;&gt;33&lt;/span&gt;:33:ff:7b:75:85 dev eth0 self permanent
01:80:c2:00:00:00 dev eth0 self permanent
01:80:c2:00:00:03 dev eth0 self permanent
01:80:c2:00:00:0e dev eth0 self permanent
&lt;span class=&quot;token number&quot;&gt;33&lt;/span&gt;:33:00:00:00:01 dev docker0 self permanent
01:00:5e:00:00:01 dev docker0 self permanent
02:42:c0:52:69:49 dev docker0 vlan &lt;span class=&quot;token number&quot;&gt;1&lt;/span&gt; master docker0 permanent
02:42:c0:52:69:49 dev docker0 master docker0 permanent
d2:04:98:13:a7:aa dev vxlan.1 dst &lt;span class=&quot;token number&quot;&gt;172.17&lt;/span&gt;.0.4 self permanent&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;指定了发往&lt;code class=&quot;language-text&quot;&gt;d2:04:98:13:a7:aa&lt;/code&gt;这个 MAC 地址（node2 VTEP 的 MAC 地址）的流量都发向&lt;code class=&quot;language-text&quot;&gt;172.17.0.4&lt;/code&gt;这个 ip。&lt;/p&gt;
&lt;p&gt;这样就可以 ping 通两台机器了：&lt;/p&gt;
&lt;p&gt;&lt;span
      class=&quot;gatsby-resp-image-wrapper&quot;
      style=&quot;position: relative; display: block; margin-left: auto; margin-right: auto; max-width: 590px; &quot;
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        loading=&quot;lazy&quot;
        decoding=&quot;async&quot;
      /&gt;
  &lt;/a&gt;
    &lt;/span&gt;&lt;/p&gt;
&lt;h5&gt;2. 实现容器&amp;#x3C;==&gt;容器通信&lt;/h5&gt;
&lt;p&gt;有了前面机器&amp;#x3C;==&gt;机器的通信基础之后，容器&amp;#x3C;==&gt;容器就比较简单了。&lt;/p&gt;
&lt;p&gt;首先需要改一下 docker 的子网，修改 docker 的启动参数并重启 docker：&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;bash&quot;&gt;&lt;pre class=&quot;language-bash&quot;&gt;&lt;code class=&quot;language-bash&quot;&gt;&lt;span class=&quot;token function&quot;&gt;cat&lt;/span&gt; &lt;span class=&quot;token operator&quot;&gt;&gt;&lt;/span&gt; /etc/docker/daemon.json &lt;span class=&quot;token operator&quot;&gt;&amp;lt;&amp;lt;&lt;/span&gt; &lt;span class=&quot;token string&quot;&gt;EOF
{&quot;bip&quot;:&quot;192.1.78.1/24&quot;}
EOF&lt;/span&gt;

systemctl restart &lt;span class=&quot;token function&quot;&gt;docker&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;然后启动 docker 容器：&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;bash&quot;&gt;&lt;pre class=&quot;language-bash&quot;&gt;&lt;code class=&quot;language-bash&quot;&gt;&lt;span class=&quot;token function&quot;&gt;docker&lt;/span&gt; run &lt;span class=&quot;token parameter variable&quot;&gt;-it&lt;/span&gt; &lt;span class=&quot;token parameter variable&quot;&gt;--rm&lt;/span&gt; busybox&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;查看一下容器的 ip 地址：&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;bash&quot;&gt;&lt;pre class=&quot;language-bash&quot;&gt;&lt;code class=&quot;language-bash&quot;&gt;/ &lt;span class=&quot;token comment&quot;&gt;# ip a&lt;/span&gt;
&lt;span class=&quot;token number&quot;&gt;1&lt;/span&gt;: lo: &lt;span class=&quot;token operator&quot;&gt;&amp;lt;&lt;/span&gt;LOOPBACK,UP,LOWER_UP&lt;span class=&quot;token operator&quot;&gt;&gt;&lt;/span&gt; mtu &lt;span class=&quot;token number&quot;&gt;65536&lt;/span&gt; qdisc noqueue qlen &lt;span class=&quot;token number&quot;&gt;1000&lt;/span&gt;
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet &lt;span class=&quot;token number&quot;&gt;127.0&lt;/span&gt;.0.1/8 scope &lt;span class=&quot;token function&quot;&gt;host&lt;/span&gt; lo
       valid_lft forever preferred_lft forever
&lt;span class=&quot;token number&quot;&gt;6&lt;/span&gt;: eth0@if7: &lt;span class=&quot;token operator&quot;&gt;&amp;lt;&lt;/span&gt;BROADCAST,MULTICAST,UP,LOWER_UP,M-DOWN&lt;span class=&quot;token operator&quot;&gt;&gt;&lt;/span&gt; mtu &lt;span class=&quot;token number&quot;&gt;1500&lt;/span&gt; qdisc noqueue
    link/ether 02:42:c0:01:4e:02 brd ff:ff:ff:ff:ff:ff
    inet &lt;span class=&quot;token number&quot;&gt;192.1&lt;/span&gt;.78.2/24 brd &lt;span class=&quot;token number&quot;&gt;192.1&lt;/span&gt;.78.255 scope global eth0
       valid_lft forever preferred_lft forever&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;在 node2 上面重复以上步骤（对应的子网地址需要改一下）。&lt;/p&gt;
&lt;p&gt;可以看到 node1 上 container 的 ip 是&lt;code class=&quot;language-text&quot;&gt;192.1.78.2&lt;/code&gt;，node2 上的 container 的 ip 是&lt;code class=&quot;language-text&quot;&gt;192.1.87.2&lt;/code&gt;，所以需要在 2 台机器上分别添加这两个 ip 的 arp 记录：&lt;/p&gt;
&lt;p&gt;Node1:&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;bash&quot;&gt;&lt;pre class=&quot;language-bash&quot;&gt;&lt;code class=&quot;language-bash&quot;&gt;&lt;span class=&quot;token builtin class-name&quot;&gt;export&lt;/span&gt; &lt;span class=&quot;token assign-left variable&quot;&gt;ANOTHER_NODE_IP&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;token number&quot;&gt;192.1&lt;/span&gt;.87.2 &lt;span class=&quot;token comment&quot;&gt;# 需要访问的另一台机器上的（容器或机器）ip&lt;/span&gt;
&lt;span class=&quot;token function&quot;&gt;ip&lt;/span&gt; neighbor &lt;span class=&quot;token function&quot;&gt;add&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$ANOTHER_NODE_IP&lt;/span&gt; lladdr &lt;span class=&quot;token variable&quot;&gt;$ANOTHER_VTEP_MAC&lt;/span&gt; dev &lt;span class=&quot;token variable&quot;&gt;$DEVICE_NAME&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;Node2:&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;bash&quot;&gt;&lt;pre class=&quot;language-bash&quot;&gt;&lt;code class=&quot;language-bash&quot;&gt;&lt;span class=&quot;token builtin class-name&quot;&gt;export&lt;/span&gt; &lt;span class=&quot;token assign-left variable&quot;&gt;ANOTHER_NODE_IP&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;token number&quot;&gt;192.1&lt;/span&gt;.78.2 &lt;span class=&quot;token comment&quot;&gt;# 需要访问的另一台机器上的（容器或机器）ip&lt;/span&gt;
&lt;span class=&quot;token function&quot;&gt;ip&lt;/span&gt; neighbor &lt;span class=&quot;token function&quot;&gt;add&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$ANOTHER_NODE_IP&lt;/span&gt; lladdr &lt;span class=&quot;token variable&quot;&gt;$ANOTHER_VTEP_MAC&lt;/span&gt; dev &lt;span class=&quot;token variable&quot;&gt;$DEVICE_NAME&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;这样就可以 ping 通容器…了吗？并没有，这时候 ping 会发现是 ping 不通的。&lt;/p&gt;
&lt;p&gt;经过很长时间的摸索，我发现是 docker 设置的 iptables 的规则阻止了 ping 包:&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;bash&quot;&gt;&lt;pre class=&quot;language-bash&quot;&gt;&lt;code class=&quot;language-bash&quot;&gt;root@VM-0-4-ubuntu:~&lt;span class=&quot;token comment&quot;&gt;# iptables -L -v&lt;/span&gt;
Chain INPUT &lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;policy ACCEPT &lt;span class=&quot;token number&quot;&gt;1322&lt;/span&gt; packets, 897K bytes&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;
 pkts bytes target     prot opt &lt;span class=&quot;token keyword&quot;&gt;in&lt;/span&gt;     out     &lt;span class=&quot;token builtin class-name&quot;&gt;source&lt;/span&gt;               destination

Chain FORWARD &lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;policy DROP &lt;span class=&quot;token number&quot;&gt;10&lt;/span&gt; packets, &lt;span class=&quot;token number&quot;&gt;840&lt;/span&gt; bytes&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;
 pkts bytes target     prot opt &lt;span class=&quot;token keyword&quot;&gt;in&lt;/span&gt;     out     &lt;span class=&quot;token builtin class-name&quot;&gt;source&lt;/span&gt;               destination
   &lt;span class=&quot;token number&quot;&gt;10&lt;/span&gt;   &lt;span class=&quot;token number&quot;&gt;840&lt;/span&gt; DOCKER-&lt;span class=&quot;token environment constant&quot;&gt;USER&lt;/span&gt;  all  --  any    any     anywhere             anywhere
   &lt;span class=&quot;token number&quot;&gt;10&lt;/span&gt;   &lt;span class=&quot;token number&quot;&gt;840&lt;/span&gt; DOCKER-ISOLATION-STAGE-1  all  --  any    any     anywhere             anywhere
    &lt;span class=&quot;token number&quot;&gt;0&lt;/span&gt;     &lt;span class=&quot;token number&quot;&gt;0&lt;/span&gt; ACCEPT     all  --  any    docker0  anywhere             anywhere             ctstate RELATED,ESTABLISHED
   &lt;span class=&quot;token number&quot;&gt;10&lt;/span&gt;   &lt;span class=&quot;token number&quot;&gt;840&lt;/span&gt; DOCKER     all  --  any    docker0  anywhere             anywhere
    &lt;span class=&quot;token number&quot;&gt;0&lt;/span&gt;     &lt;span class=&quot;token number&quot;&gt;0&lt;/span&gt; ACCEPT     all  --  docker0 &lt;span class=&quot;token operator&quot;&gt;!&lt;/span&gt;docker0  anywhere             anywhere
    &lt;span class=&quot;token number&quot;&gt;0&lt;/span&gt;     &lt;span class=&quot;token number&quot;&gt;0&lt;/span&gt; ACCEPT     all  --  docker0 docker0  anywhere             anywhere

Chain OUTPUT &lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;policy ACCEPT &lt;span class=&quot;token number&quot;&gt;1294&lt;/span&gt; packets, 147K bytes&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;
 pkts bytes target     prot opt &lt;span class=&quot;token keyword&quot;&gt;in&lt;/span&gt;     out     &lt;span class=&quot;token builtin class-name&quot;&gt;source&lt;/span&gt;               destination

Chain DOCKER &lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token number&quot;&gt;1&lt;/span&gt; references&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;
 pkts bytes target     prot opt &lt;span class=&quot;token keyword&quot;&gt;in&lt;/span&gt;     out     &lt;span class=&quot;token builtin class-name&quot;&gt;source&lt;/span&gt;               destination

Chain DOCKER-ISOLATION-STAGE-1 &lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token number&quot;&gt;1&lt;/span&gt; references&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;
 pkts bytes target     prot opt &lt;span class=&quot;token keyword&quot;&gt;in&lt;/span&gt;     out     &lt;span class=&quot;token builtin class-name&quot;&gt;source&lt;/span&gt;               destination
    &lt;span class=&quot;token number&quot;&gt;0&lt;/span&gt;     &lt;span class=&quot;token number&quot;&gt;0&lt;/span&gt; DOCKER-ISOLATION-STAGE-2  all  --  docker0 &lt;span class=&quot;token operator&quot;&gt;!&lt;/span&gt;docker0  anywhere             anywhere
   &lt;span class=&quot;token number&quot;&gt;10&lt;/span&gt;   &lt;span class=&quot;token number&quot;&gt;840&lt;/span&gt; RETURN     all  --  any    any     anywhere             anywhere

Chain DOCKER-ISOLATION-STAGE-2 &lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token number&quot;&gt;1&lt;/span&gt; references&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;
 pkts bytes target     prot opt &lt;span class=&quot;token keyword&quot;&gt;in&lt;/span&gt;     out     &lt;span class=&quot;token builtin class-name&quot;&gt;source&lt;/span&gt;               destination
    &lt;span class=&quot;token number&quot;&gt;0&lt;/span&gt;     &lt;span class=&quot;token number&quot;&gt;0&lt;/span&gt; DROP       all  --  any    docker0  anywhere             anywhere
    &lt;span class=&quot;token number&quot;&gt;0&lt;/span&gt;     &lt;span class=&quot;token number&quot;&gt;0&lt;/span&gt; RETURN     all  --  any    any     anywhere             anywhere

Chain DOCKER-&lt;span class=&quot;token environment constant&quot;&gt;USER&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token number&quot;&gt;1&lt;/span&gt; references&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;
 pkts bytes target     prot opt &lt;span class=&quot;token keyword&quot;&gt;in&lt;/span&gt;     out     &lt;span class=&quot;token builtin class-name&quot;&gt;source&lt;/span&gt;               destination
   &lt;span class=&quot;token number&quot;&gt;10&lt;/span&gt;   &lt;span class=&quot;token number&quot;&gt;840&lt;/span&gt; RETURN     all  --  any    any     anywhere             anywhere&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;iptables 的&lt;code class=&quot;language-text&quot;&gt;FORWARD&lt;/code&gt;chain 阻止了包从&lt;code class=&quot;language-text&quot;&gt;vxlan.1&lt;/code&gt; 到&lt;code class=&quot;language-text&quot;&gt;docker0&lt;/code&gt;interface 的 forward，所以导致 ping 不通。这里不细究&lt;code class=&quot;language-text&quot;&gt;FORWARD&lt;/code&gt;chain 下的 iptables 规则，先简单直接地把&lt;code class=&quot;language-text&quot;&gt;FORWARD&lt;/code&gt;chain 的默认 policy 设置为&lt;code class=&quot;language-text&quot;&gt;ACCEPT&lt;/code&gt;：&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;text&quot;&gt;&lt;pre class=&quot;language-text&quot;&gt;&lt;code class=&quot;language-text&quot;&gt;iptables -P FORWARD ACCEPT&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;这样 2 个容器之间就可以 ping 通了：&lt;/p&gt;
&lt;p&gt;&lt;span
      class=&quot;gatsby-resp-image-wrapper&quot;
      style=&quot;position: relative; display: block; margin-left: auto; margin-right: auto; max-width: 590px; &quot;
    &gt;
      &lt;a
    class=&quot;gatsby-resp-image-link&quot;
    href=&quot;/static/43cf0a876f7d5381e7b9f1d2dc7b1fb5/cc6fe/image-20191223192249290.png&quot;
    style=&quot;display: block&quot;
    target=&quot;_blank&quot;
    rel=&quot;noopener&quot;
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    &lt;span
    class=&quot;gatsby-resp-image-background-image&quot;
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  &gt;&lt;/span&gt;
  &lt;img
        class=&quot;gatsby-resp-image-image&quot;
        alt=&quot;image-20191223192249290&quot;
        title=&quot;&quot;
        src=&quot;/static/43cf0a876f7d5381e7b9f1d2dc7b1fb5/fcda8/image-20191223192249290.png&quot;
        srcset=&quot;/static/43cf0a876f7d5381e7b9f1d2dc7b1fb5/12f09/image-20191223192249290.png 148w,
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        sizes=&quot;(max-width: 590px) 100vw, 590px&quot;
        style=&quot;width:100%;height:100%;margin:0;vertical-align:middle;position:absolute;top:0;left:0;&quot;
        loading=&quot;lazy&quot;
        decoding=&quot;async&quot;
      /&gt;
  &lt;/a&gt;
    &lt;/span&gt;&lt;/p&gt;
&lt;h3&gt;Flannel and VXLAN&lt;/h3&gt;
&lt;p&gt;Flannel 和 VXLAN 有什么关系？&lt;/p&gt;
&lt;p&gt;Flannel 采用搭建 overlay 网络的方法来满足&lt;a href=&quot;https://kubernetes.io/docs/concepts/cluster-administration/networking/#the-kubernetes-network-model&quot;&gt;k8s 的网络模型&lt;/a&gt;，它提供了几个不通的 backend 来搭建 overlay 网络，其中 VXLAN 是最推荐的一个 backend。VXLAN 在 linux 内核中有良好支持，性能好。&lt;/p&gt;
&lt;p&gt;Flannel 利用 VXLAN 来构建 overlay 网络，本身只维护几个表，其余工作都是 VXLAN 完成。基本原理和上面的手工操作是一样的，只是 flannel 把这个过程自动化了。&lt;/p&gt;
&lt;p&gt;Flannel 一共迭代了 3 个版本：&lt;/p&gt;
&lt;h4&gt;第一版&lt;/h4&gt;
&lt;p&gt;每个机器上的 flannel daemon 会创建 VXLAN interface，并把自己注册为 L2MISS 和 L3MISS 事件的 handler。&lt;/p&gt;
&lt;p&gt;L2MISS 是在 2 层网络的 miss，也就是从 IP 查找 MAC 这一步的 miss（对应上面的地址 2）。Flannel daemon 收到 miss 后会查找存储的数据来给出对应的 MAC 地址，并将其加入 arp 缓存。&lt;/p&gt;
&lt;p&gt;L3MISS 是 host 不知道某个 MAC 地址应该发往哪里时产生的 miss（对应上面的地址 3）。收到 miss 后给出 ip 地址，并加入 fdb。&lt;/p&gt;
&lt;p&gt;这个版本每个机器上需要有：&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;1 条路由表记录（指向 VXLAN interface）&lt;/li&gt;
&lt;li&gt;每个最近通信过的 container1 条 arp 表记录&lt;/li&gt;
&lt;li&gt;每个主机 1 条 fdb 表记录&lt;/li&gt;
&lt;/ul&gt;
&lt;h4&gt;第二版&lt;/h4&gt;
&lt;p&gt;去掉 L3MISS handler。每次新机器加入集群时，直接添加在所有主机上添加好所需的 fdb 记录。&lt;/p&gt;
&lt;h4&gt;第三版&lt;/h4&gt;
&lt;p&gt;去掉 L2MISS handler。需要添加 n-1 条路由表记录，这些路由表记录和前面不同的是，除了将路由指向 VXLAN interface，还指定了通过 VXLAN 之后下一跳的地址（对应主机的 ip 地址）。这样就只需要每个主机 1 条 arp 记录，以及每个主机 1 条 fdb 记录。&lt;/p&gt;
&lt;p&gt;这样 flannel daemon 就不需要监听任何内核的事件，只需要在机器加入、退出集群的时候维护好这些记录。即使 flannel daemon 挂了整个 overlay 网络还是能（在很长一段时间内）正常运行。&lt;/p&gt;
&lt;h3&gt;Reference&lt;/h3&gt;
&lt;ol&gt;
&lt;li&gt;&lt;a href=&quot;https://github.com/yangyuqian/k8s-the-hard-way/blob/master/network/vxlan-flannel-cn.md&quot;&gt;vxlan 在 Flannel 中的 Overlay 网络的实现&lt;/a&gt;&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;https://cizixs.com/2017/09/25/vxlan-protocol-introduction/&quot;&gt;vxlan 协议原理简介&lt;/a&gt;&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;https://www.sdnlab.com/21143.html&quot;&gt;容器 Flannel vxlan 基本原理和验证&lt;/a&gt;&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;https://tools.ietf.org/html/rfc7348&quot;&gt;rfc7348&lt;/a&gt;&lt;/li&gt;
&lt;li&gt;&lt;a href=&quot;https://github.com/coreos/Flannel/blob/master/backend/vxlan/vxlan.go#L18&quot;&gt;Flannel design notes and history&lt;/a&gt;&lt;/li&gt;
&lt;/ol&gt;</content:encoded></item><item><title><![CDATA[Kubernetes 101]]></title><description><![CDATA[Kubernetes 101 Notion Kubeadm 安装 k8s Notion]]></description><link>https://mingxinwei.github.io/Kubernenes 101/</link><guid isPermaLink="false">https://mingxinwei.github.io/Kubernenes 101/</guid><pubDate>Mon, 21 Oct 2019 10:51:30 GMT</pubDate><content:encoded>&lt;h3&gt;Kubernetes 101&lt;/h3&gt;
&lt;p&gt;&lt;a href=&quot;https://www.notion.so/shuataren/Kubernetes-101-d1cf0021fbc846c9a846a7656f6a4da5&quot;&gt;Notion&lt;/a&gt;&lt;/p&gt;
&lt;h2&gt;Kubeadm 安装 k8s&lt;/h2&gt;
&lt;p&gt;&lt;a href=&quot;https://www.notion.so/shuataren/Kubeadm-k8s-1ba0fc8ee5954255b25b7315b0bf0aa3&quot;&gt;Notion&lt;/a&gt;&lt;/p&gt;</content:encoded></item><item><title><![CDATA[重新定义cd命令]]></title><description><![CDATA[折腾vim…]]></description><link>https://mingxinwei.github.io/Redefine cd/</link><guid isPermaLink="false">https://mingxinwei.github.io/Redefine cd/</guid><pubDate>Sat, 15 Jun 2019 10:20:30 GMT</pubDate><content:encoded>&lt;p&gt;折腾vim的时候发现一位插件作者的有趣小工具：&lt;a href=&quot;https://zhuanlan.zhihu.com/p/35015221&quot;&gt;想跳转到一个目录，却只记得几个字母&lt;/a&gt;。&lt;/p&gt;
&lt;p&gt;按照文章里面的思路操作之后使用了几天，果然比原来方便一些。不过也注意到有一些可以改进的地方。&lt;/p&gt;
&lt;p&gt;首先是这个工具使用了另外一个名字&lt;code class=&quot;language-text&quot;&gt;j&lt;/code&gt;，在每次需要目录跳转的时候需要和&lt;code class=&quot;language-text&quot;&gt;cd&lt;/code&gt;命令做区分：当需要正常跳转的时候用&lt;code class=&quot;language-text&quot;&gt;cd&lt;/code&gt;；模糊跳转的时候使用&lt;code class=&quot;language-text&quot;&gt;j&lt;/code&gt;。这也是我使用&lt;code class=&quot;language-text&quot;&gt;z&lt;/code&gt;时候的一个痛点，对于&lt;code class=&quot;language-text&quot;&gt;cd&lt;/code&gt;这样一个高频命令每次输入前需要在脑子里做个if还挺累的。&lt;/p&gt;
&lt;p&gt;所以我往前再进一步，直接把覆盖&lt;code class=&quot;language-text&quot;&gt;cd&lt;/code&gt;命令，在不不改变&lt;code class=&quot;language-text&quot;&gt;cd&lt;/code&gt;原有功能的前提下，增加了对历史访问过的目录的模糊跳转。(使用zsh)&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;bash&quot;&gt;&lt;pre class=&quot;language-bash&quot;&gt;&lt;code class=&quot;language-bash&quot;&gt;&lt;span class=&quot;token keyword&quot;&gt;function&lt;/span&gt; &lt;span class=&quot;token function-name function&quot;&gt;cd&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;{&lt;/span&gt;
  &lt;span class=&quot;token builtin class-name&quot;&gt;builtin&lt;/span&gt; &lt;span class=&quot;token builtin class-name&quot;&gt;cd&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$1&lt;/span&gt; &lt;span class=&quot;token operator&quot;&gt;&lt;span class=&quot;token file-descriptor important&quot;&gt;2&lt;/span&gt;&gt;&lt;/span&gt;/dev/null
  &lt;span class=&quot;token keyword&quot;&gt;if&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;[&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$?&lt;/span&gt; &lt;span class=&quot;token parameter variable&quot;&gt;-ne&lt;/span&gt; &lt;span class=&quot;token number&quot;&gt;0&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;]&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt;
  &lt;span class=&quot;token keyword&quot;&gt;then&lt;/span&gt;
    &lt;span class=&quot;token assign-left variable&quot;&gt;dir&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt;&lt;span class=&quot;token variable&quot;&gt;&lt;span class=&quot;token variable&quot;&gt;$(&lt;/span&gt;desc_z_history &lt;span class=&quot;token operator&quot;&gt;|&lt;/span&gt; fzy &lt;span class=&quot;token parameter variable&quot;&gt;--query&lt;/span&gt; $1&lt;span class=&quot;token variable&quot;&gt;)&lt;/span&gt;&lt;/span&gt;
    &lt;span class=&quot;token keyword&quot;&gt;if&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;[&lt;/span&gt; &lt;span class=&quot;token string&quot;&gt;&quot;&lt;span class=&quot;token variable&quot;&gt;$dir&lt;/span&gt;&quot;&lt;/span&gt; &lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;token string&quot;&gt;&quot;&lt;span class=&quot;token variable&quot;&gt;$1&lt;/span&gt;&quot;&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;]&lt;/span&gt; &lt;span class=&quot;token operator&quot;&gt;||&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;[&lt;/span&gt; &lt;span class=&quot;token parameter variable&quot;&gt;-z&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$dir&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;]&lt;/span&gt;
    &lt;span class=&quot;token keyword&quot;&gt;then&lt;/span&gt;
      &lt;span class=&quot;token builtin class-name&quot;&gt;return&lt;/span&gt;
    &lt;span class=&quot;token keyword&quot;&gt;else&lt;/span&gt;
      &lt;span class=&quot;token builtin class-name&quot;&gt;builtin&lt;/span&gt; &lt;span class=&quot;token builtin class-name&quot;&gt;cd&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$dir&lt;/span&gt;
    &lt;span class=&quot;token keyword&quot;&gt;fi&lt;/span&gt;
  &lt;span class=&quot;token keyword&quot;&gt;fi&lt;/span&gt;
&lt;span class=&quot;token punctuation&quot;&gt;}&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;还有一个可优化的点是性能，在使用js脚本时会感知到命令启动有一点卡顿。&lt;/p&gt;
&lt;p&gt;使用js脚本当然很方便，不过他的启动时间相比小runtime的编译型语言来说还是差很多。而在&lt;code class=&quot;language-text&quot;&gt;cd&lt;/code&gt;这样的命令里，延时是比较重要的。&lt;/p&gt;
&lt;p&gt;测量一下：&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;text&quot;&gt;&lt;pre class=&quot;language-text&quot;&gt;&lt;code class=&quot;language-text&quot;&gt;-&gt;  time descZHistory
descZHistory  0.06s user 0.02s system 95% cpu 0.091 total&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;执行时间接近100ms。再看一下Node自己启动的时间：&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;text&quot;&gt;&lt;pre class=&quot;language-text&quot;&gt;&lt;code class=&quot;language-text&quot;&gt;-&gt;  time node -e &apos;&apos;
node -e &apos;&apos;  0.06s user 0.02s system 95% cpu 0.080 total&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;Node自己启动的时间就达到80-90ms左右，在这个场景下是不可忍受的。&lt;/p&gt;
&lt;p&gt;所以换用Rust实现:&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;rust&quot;&gt;&lt;pre class=&quot;language-rust&quot;&gt;&lt;code class=&quot;language-rust&quot;&gt;&lt;span class=&quot;token keyword&quot;&gt;use&lt;/span&gt; dirs&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt;
&lt;span class=&quot;token keyword&quot;&gt;use&lt;/span&gt; regex&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt;
&lt;span class=&quot;token keyword&quot;&gt;use&lt;/span&gt; &lt;span class=&quot;token namespace&quot;&gt;std&lt;span class=&quot;token punctuation&quot;&gt;::&lt;/span&gt;&lt;/span&gt;fs&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt;
&lt;span class=&quot;token keyword&quot;&gt;use&lt;/span&gt; &lt;span class=&quot;token namespace&quot;&gt;std&lt;span class=&quot;token punctuation&quot;&gt;::&lt;/span&gt;io&lt;span class=&quot;token punctuation&quot;&gt;::&lt;/span&gt;&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;{&lt;/span&gt;&lt;span class=&quot;token keyword&quot;&gt;self&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;token class-name&quot;&gt;Write&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt;

&lt;span class=&quot;token keyword&quot;&gt;fn&lt;/span&gt; &lt;span class=&quot;token function-definition function&quot;&gt;main&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;{&lt;/span&gt;
    &lt;span class=&quot;token keyword&quot;&gt;if&lt;/span&gt; &lt;span class=&quot;token keyword&quot;&gt;let&lt;/span&gt; &lt;span class=&quot;token class-name&quot;&gt;Some&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;home_dir&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt; &lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;token namespace&quot;&gt;dirs&lt;span class=&quot;token punctuation&quot;&gt;::&lt;/span&gt;&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;home_dir&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;{&lt;/span&gt;
        &lt;span class=&quot;token keyword&quot;&gt;let&lt;/span&gt; data &lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;token namespace&quot;&gt;fs&lt;span class=&quot;token punctuation&quot;&gt;::&lt;/span&gt;&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;read_to_string&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;home_dir&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;as_path&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;join&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token string&quot;&gt;&quot;.z&quot;&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;expect&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token string&quot;&gt;&quot;Open file&quot;&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt;
        &lt;span class=&quot;token keyword&quot;&gt;let&lt;/span&gt; re &lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;token namespace&quot;&gt;regex&lt;span class=&quot;token punctuation&quot;&gt;::&lt;/span&gt;&lt;/span&gt;&lt;span class=&quot;token class-name&quot;&gt;Regex&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;::&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;new&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token string&quot;&gt;r&quot;\d+$&quot;&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;unwrap&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt;
        &lt;span class=&quot;token keyword&quot;&gt;let&lt;/span&gt; &lt;span class=&quot;token keyword&quot;&gt;mut&lt;/span&gt; lines&lt;span class=&quot;token punctuation&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;token class-name&quot;&gt;Vec&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;&amp;lt;&lt;/span&gt;&lt;span class=&quot;token class-name&quot;&gt;Vec&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;&amp;lt;&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;&amp;amp;&lt;/span&gt;&lt;span class=&quot;token keyword&quot;&gt;str&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;&gt;&gt;&lt;/span&gt; &lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; data
            &lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;lines&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;
            &lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;filter&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token closure-params&quot;&gt;&lt;span class=&quot;token closure-punctuation punctuation&quot;&gt;|&lt;/span&gt;l&lt;span class=&quot;token closure-punctuation punctuation&quot;&gt;|&lt;/span&gt;&lt;/span&gt; re&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;is_match&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;l&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;
            &lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;map&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token closure-params&quot;&gt;&lt;span class=&quot;token closure-punctuation punctuation&quot;&gt;|&lt;/span&gt;l&lt;span class=&quot;token closure-punctuation punctuation&quot;&gt;|&lt;/span&gt;&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;{&lt;/span&gt;
                &lt;span class=&quot;token keyword&quot;&gt;let&lt;/span&gt; arr&lt;span class=&quot;token punctuation&quot;&gt;:&lt;/span&gt; &lt;span class=&quot;token class-name&quot;&gt;Vec&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;&amp;lt;&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;&amp;amp;&lt;/span&gt;&lt;span class=&quot;token keyword&quot;&gt;str&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;&gt;&lt;/span&gt; &lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; l&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;split&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token char&quot;&gt;&apos;|&apos;&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;collect&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt;
                arr
            &lt;span class=&quot;token punctuation&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;
            &lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;collect&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt;
        lines&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;sort_by&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token closure-params&quot;&gt;&lt;span class=&quot;token closure-punctuation punctuation&quot;&gt;|&lt;/span&gt;a&lt;span class=&quot;token punctuation&quot;&gt;,&lt;/span&gt; b&lt;span class=&quot;token closure-punctuation punctuation&quot;&gt;|&lt;/span&gt;&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;{&lt;/span&gt;
            &lt;span class=&quot;token keyword&quot;&gt;let&lt;/span&gt; score_a &lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; a&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;get&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token number&quot;&gt;1&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;unwrap&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;parse&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;::&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;&amp;lt;&lt;/span&gt;&lt;span class=&quot;token keyword&quot;&gt;f64&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;&gt;&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;unwrap&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt;
            &lt;span class=&quot;token keyword&quot;&gt;let&lt;/span&gt; score_b &lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; b&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;get&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token number&quot;&gt;1&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;unwrap&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;parse&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;::&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;&amp;lt;&lt;/span&gt;&lt;span class=&quot;token keyword&quot;&gt;f64&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;&gt;&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;unwrap&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt;
            score_b&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;partial_cmp&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token operator&quot;&gt;&amp;amp;&lt;/span&gt;score_a&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;unwrap&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;
        &lt;span class=&quot;token punctuation&quot;&gt;}&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt;
        &lt;span class=&quot;token keyword&quot;&gt;let&lt;/span&gt; stdout &lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;token namespace&quot;&gt;io&lt;span class=&quot;token punctuation&quot;&gt;::&lt;/span&gt;&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;stdout&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt;
        &lt;span class=&quot;token keyword&quot;&gt;let&lt;/span&gt; &lt;span class=&quot;token keyword&quot;&gt;mut&lt;/span&gt; handle &lt;span class=&quot;token operator&quot;&gt;=&lt;/span&gt; &lt;span class=&quot;token namespace&quot;&gt;io&lt;span class=&quot;token punctuation&quot;&gt;::&lt;/span&gt;&lt;/span&gt;&lt;span class=&quot;token class-name&quot;&gt;BufWriter&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;::&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;new&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;stdout&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;lock&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt;
        &lt;span class=&quot;token keyword&quot;&gt;for&lt;/span&gt; l &lt;span class=&quot;token keyword&quot;&gt;in&lt;/span&gt; lines&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;iter&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;{&lt;/span&gt;
            &lt;span class=&quot;token macro property&quot;&gt;writeln!&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;handle&lt;span class=&quot;token punctuation&quot;&gt;,&lt;/span&gt; &lt;span class=&quot;token string&quot;&gt;&quot;{}&quot;&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;,&lt;/span&gt; l&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;get&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token number&quot;&gt;0&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;unwrap&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;.&lt;/span&gt;&lt;span class=&quot;token function&quot;&gt;unwrap&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt;
        &lt;span class=&quot;token punctuation&quot;&gt;}&lt;/span&gt;
    &lt;span class=&quot;token punctuation&quot;&gt;}&lt;/span&gt; &lt;span class=&quot;token keyword&quot;&gt;else&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;{&lt;/span&gt;
        &lt;span class=&quot;token macro property&quot;&gt;eprintln!&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token string&quot;&gt;&quot;Can not get home dir&quot;&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt;
    &lt;span class=&quot;token punctuation&quot;&gt;}&lt;/span&gt;
&lt;span class=&quot;token punctuation&quot;&gt;}&lt;/span&gt;
&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;Rust的结果：&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;text&quot;&gt;&lt;pre class=&quot;language-text&quot;&gt;&lt;code class=&quot;language-text&quot;&gt;-&gt;  time desc_z_history
desc_z_history  0.00s user 0.00s system 34% cpu 0.010 total&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;
&lt;p&gt;整个程序的时间能控制在10-20ms左右，达到要求了。&lt;/p&gt;
&lt;p&gt;这样这个命令就比较令人满意了，在这个命令的基础上可以做一些小拓展，例如我加了一些打开常用编辑器的辅助命令，实现模糊查询并使用编辑器打开某个项目/文件：&lt;/p&gt;
&lt;div class=&quot;gatsby-highlight&quot; data-language=&quot;bash&quot;&gt;&lt;pre class=&quot;language-bash&quot;&gt;&lt;code class=&quot;language-bash&quot;&gt;&lt;span class=&quot;token keyword&quot;&gt;function&lt;/span&gt; &lt;span class=&quot;token function-name function&quot;&gt;code_editor_base&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;{&lt;/span&gt;
  &lt;span class=&quot;token keyword&quot;&gt;if&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;[&lt;/span&gt; &lt;span class=&quot;token parameter variable&quot;&gt;-z&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$2&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;]&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt; &lt;span class=&quot;token comment&quot;&gt;# if not passing parameter, open current directory&lt;/span&gt;
  &lt;span class=&quot;token keyword&quot;&gt;then&lt;/span&gt;
    &lt;span class=&quot;token variable&quot;&gt;$1&lt;/span&gt; &lt;span class=&quot;token builtin class-name&quot;&gt;.&lt;/span&gt;
    &lt;span class=&quot;token builtin class-name&quot;&gt;return&lt;/span&gt;
  &lt;span class=&quot;token keyword&quot;&gt;fi&lt;/span&gt;

  &lt;span class=&quot;token keyword&quot;&gt;if&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;[&lt;/span&gt; &lt;span class=&quot;token parameter variable&quot;&gt;-f&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$2&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;]&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;;&lt;/span&gt; &lt;span class=&quot;token comment&quot;&gt;# if file exists, open the file directly&lt;/span&gt;
  &lt;span class=&quot;token keyword&quot;&gt;then&lt;/span&gt;
    &lt;span class=&quot;token variable&quot;&gt;$1&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$2&lt;/span&gt;
  &lt;span class=&quot;token keyword&quot;&gt;else&lt;/span&gt;
    &lt;span class=&quot;token builtin class-name&quot;&gt;cd&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$2&lt;/span&gt;
    &lt;span class=&quot;token variable&quot;&gt;$1&lt;/span&gt; &lt;span class=&quot;token builtin class-name&quot;&gt;.&lt;/span&gt;
  &lt;span class=&quot;token keyword&quot;&gt;fi&lt;/span&gt;
&lt;span class=&quot;token punctuation&quot;&gt;}&lt;/span&gt;

&lt;span class=&quot;token keyword&quot;&gt;function&lt;/span&gt; &lt;span class=&quot;token function-name function&quot;&gt;c&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;{&lt;/span&gt;
  code_editor_base code &lt;span class=&quot;token variable&quot;&gt;$1&lt;/span&gt;
&lt;span class=&quot;token punctuation&quot;&gt;}&lt;/span&gt;

&lt;span class=&quot;token keyword&quot;&gt;function&lt;/span&gt; &lt;span class=&quot;token function-name function&quot;&gt;v&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;{&lt;/span&gt;
  code_editor_base &lt;span class=&quot;token function&quot;&gt;vim&lt;/span&gt; &lt;span class=&quot;token variable&quot;&gt;$1&lt;/span&gt;
&lt;span class=&quot;token punctuation&quot;&gt;}&lt;/span&gt;

&lt;span class=&quot;token keyword&quot;&gt;function&lt;/span&gt; &lt;span class=&quot;token function-name function&quot;&gt;gol&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;{&lt;/span&gt;
  code_editor_base goland &lt;span class=&quot;token variable&quot;&gt;$1&lt;/span&gt;
&lt;span class=&quot;token punctuation&quot;&gt;}&lt;/span&gt;

&lt;span class=&quot;token keyword&quot;&gt;function&lt;/span&gt; &lt;span class=&quot;token function-name function&quot;&gt;cha&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;{&lt;/span&gt;
  code_editor_base charm &lt;span class=&quot;token variable&quot;&gt;$1&lt;/span&gt;
&lt;span class=&quot;token punctuation&quot;&gt;}&lt;/span&gt;
&lt;span class=&quot;token keyword&quot;&gt;function&lt;/span&gt; &lt;span class=&quot;token function-name function&quot;&gt;i&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;(&lt;/span&gt;&lt;span class=&quot;token punctuation&quot;&gt;)&lt;/span&gt; &lt;span class=&quot;token punctuation&quot;&gt;{&lt;/span&gt;
  code_editor_base idea &lt;span class=&quot;token variable&quot;&gt;$1&lt;/span&gt;
&lt;span class=&quot;token punctuation&quot;&gt;}&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/div&gt;</content:encoded></item></channel></rss>