linux查询指定ip端口号(linux查看端口号的命令怎么读)

尽管搞IT多年，但一些基本性的概念却依旧似懂非懂，就好比说什么是端口号？你说知道吧，确实知道，每个程序都有个自己的端口号，有些都是约定俗称的，比如FTP端口21、SFTP端口22、IIS端口80等等。可是让你去细细解释一下，还真不一定能回答上来。

什么是端口号？

我们都知道，每台联网的计算机都有自己的IP，这个IP好比是在互联网上的地址编号，是唯一的，这样才能通过IP地址正常通信。那么问题就来了，一台计算机它可能会提供多个服务，比如Apache服务、FTP服务、Email服务等等，通过IP地址来区分显示是不可能的。这个时候我们就需要用端口来进行区分，每个服务对应指定的端口，这样通过IP+端口就能唯一确定要访问的服务了。

为了统一整个互联网的端口和网络服务的对应关系，以便让所有的主机都能使用相同的机制来请求或提供服务，同一个服务使用相同的端口，这就是协议。

计算机中的协议主要分为两大类：面向连接的可靠的TCP协议（Transmission Control Protocol，传输控制协议）；面向无连接的不可靠的UDP协议（User Datagram Protocol，用户数据报协议）。这么多的端口，我们该如何知道哪个端口对应哪个呢？其实在linux系统中，提供了/etc/services的文件，可以进行查看。

端口信息查看方法（进程号与的端口号均可查看）

以下的命令较多，详细的用法不必深究，先记住固定用法，后期遇到了再细讲。

方法 1：使用 ss 命令

ss 一般用于转储套接字统计信息，类似于 netstat 输出的信息，但它显示了更多的 TCP 信息和状态信息。它还可以显示所有类型的套接字统计信息，包括 PACKET、TCP、UDP、DCCP、RAW、Unix 域等。

[root@localhost ~]<span>#  ss -tnlp | grep dmserver</span>State      Recv-Q Send-Q          Local <span>Address:</span>Port                         Peer <span>Address:</span>Port              LISTEN     <span>0</span>      <span>5</span>                           *<span>:</span><span>5900</span>                                    *<span>:*</span>                   <span>users:</span>          LISTEN     <span>0</span>      <span>128</span>         <span>:</span><span>:</span><span>:</span><span>5236</span>                    <span>:</span><span>:</span><span>:*</span>                   <span>users:</span>((<span>\"dmserver\"</span>,pid=<span>7060</span>,fd=<span>4</span>))[root@localhost ~]<span># </span>

方法 2：使用 netstat 命令

netstat 能够显示网络连接、路由表、接口统计信息、伪装连接以及多播成员。既然已经会用ss的高级命令了，就忘记它吧。

<span>[root@localhost</span> <span>~]#</span> <span>netstat</span> <span>-tnlp</span><span>Active</span> <span>Internet</span> <span>connections</span> <span>(only</span> <span>servers)</span><span>Proto</span> <span>Recv-Q</span> <span>Send-Q</span> <span>Local</span> <span>Address</span>           <span>Foreign</span> <span>Address</span>         <span>State</span>       <span>PID/Program</span> <span>name</span>    <span>tcp6</span>       <span>0</span>      <span>0</span> <span>:::4236</span>                 <span>:::*</span>                    <span>LISTEN</span>      <span>7059</span><span>/dmap</span>               <span>tcp6</span>       <span>0</span>      <span>0</span> <span>:::5236</span>                 <span>:::*</span>                    <span>LISTEN</span>      <span>7060</span><span>/dmserver</span>       <span>tcp6</span>       <span>0</span>      <span>0</span> <span>:::22</span>                   <span>:::*</span>                    <span>LISTEN</span>      <span>6831</span><span>/sshd</span>           <span>tcp6</span>       <span>0</span>      <span>0</span> <span>::1:631</span>                 <span>:::*</span>                    <span>LISTEN</span>      <span>6832</span><span>/cupsd</span>          <span>tcp6</span>       <span>0</span>      <span>0</span> <span>::1:25</span>                  <span>:::*</span>                    <span>LISTEN</span>      <span>7225</span><span>/master</span>         <span>[root@localhost</span> <span>~]#</span> 

方法 3：使用 fuser 命令

fuser 工具会将本地系统上打开了文件的进程的进程 ID 显示在标准输出中，一般通过端口去查看对应的进程和和用户。

<span>[root@localhost</span> <span>~]#</span> <span>fuser</span> <span>-v</span>  <span>5236</span><span>/tcp</span>                     <span>用户</span>     <span>进程号</span> <span>权限</span>   <span>命令</span><span>5236/tcp:</span>            <span>dmdba</span>      <span>7060</span> <span>F....</span> <span>dmserver</span>

方法 4：使用 nmap 命令

nmap（“Network Mapper”）是一款用于网络检测和安全审计的开源工具。它最初用于对大型网络进行快速扫描，但它对于单个主机的扫描也有很好的表现。

nmap 使用原始 IP 数据包来确定网络上可用的主机，这些主机的服务（包括应用程序名称和版本）、主机运行的操作系统（包括操作系统版本等信息）、正在使用的数据包过滤器或防火墙的类型，以及很多其它信息。

<span>[root@localhost</span> <span>~]#</span> <span>nmap</span> <span>-sV</span> <span>-p</span> <span>5236</span> <span>localhost</span><span>Starting</span> <span>Nmap</span> <span>6.40</span> <span>(</span> <span>http://nmap.org</span> <span>)</span> <span>at</span> <span>2021</span><span>-01</span><span>-01</span> <span>00</span><span>:23</span> <span>CST</span><span>mass_dns: warning:</span> <span>Unable</span> <span>to</span> <span>determine</span> <span>any</span> <span>DNS</span> <span>servers.</span> <span>Reverse</span> <span>DNS</span> <span>is</span> <span>disabled.</span> <span>Try</span> <span>using</span> <span>--system-dns</span> <span>or</span> <span>specify</span> <span>valid</span> <span>servers</span> <span>with</span> <span>--dns-servers</span><span>Nmap</span> <span>scan</span> <span>report</span> <span>for</span> <span>localhost</span> <span>(127.0.0.1)</span><span>Host</span> <span>is</span> <span>up</span> <span>(0.00031s</span> <span>latency).</span><span>Other</span> <span>addresses</span> <span>for</span> <span>localhost</span> <span>(not</span> <span>scanned):</span> <span>127.0</span><span>.0</span><span>.1</span><span>PORT</span>     <span>STATE</span> <span>SERVICE</span>    <span>VERSION</span><span>5236</span><span>/tcp</span> <span>open</span>  <span>tcpwrapped</span><span>Service</span> <span>detection</span> <span>performed.</span> <span>Please</span> <span>report</span> <span>any</span> <span>incorrect</span> <span>results</span> <span>at</span> <span>http://nmap.org/submit/</span> <span>.</span><span>Nmap done:</span> <span>1</span> <span>IP</span> <span>address</span> <span>(1</span> <span>host</span> <span>up)</span> <span>scanned</span> <span>in</span> <span>10.91</span> <span>seconds</span>

可以看出，对于普通用户来说，该命令似乎并不好用，也看得不大懂，还需要注意的是该命令一般不会默认安装，需要额外安装。

方法 5：使用 systemctl 命令

systemctl 是 systemd 系统的控制管理器和服务管理器，通过systemctl可以查看服务的具体运行信息，包括PID、是否自启、启动命令等。很遗憾，通过该命令只能查看到对应的PID进程号，如果要查看对应的端口号，可以通过本文中其他端口号、进程号查看方法进行互查。

<span>[root@localhost</span> <span>~]#</span> <span>systemctl</span> <span>status</span> <span>DmServiceDMSERVER.service</span> <span>●</span> <span>DmServiceDMSERVER.service</span> <span>-</span> <span>DM</span> <span>database</span> <span>instance</span> <span>service</span>   <span>Loaded:</span> <span>loaded</span> <span>(/usr/lib/systemd/system/DmServiceDMSERVER.service;</span> <span>enabled;</span> <span>vendor preset:</span> <span>disabled)</span>   <span>Active:</span> <span>active</span> <span>(running)</span> <span>since</span> <span>一</span> <span>2021</span><span>-03</span><span>-22</span> <span>16</span><span>:33:05</span> <span>CST;</span> <span>15h</span> <span>ago</span>  <span>Process:</span> <span>6837</span> <span>ExecStart=/soft/dmdb/bin/DmServiceDMSERVER</span> <span>start</span> <span>(code=exited,</span> <span>status=0/SUCCESS)</span> <span>Main PID:</span> <span>7060</span> <span>(dmserver)</span>    <span>Tasks:</span> <span>54</span>   <span>CGroup:</span> <span>/system.slice/DmServiceDMSERVER.service</span>           <span>└─7060</span> <span>/soft/dmdb/bin/dmserver</span> <span>/soft/dmdb/data/DAMENG/dm.ini</span> <span>-noconsole</span><span>3</span><span>月</span> <span>22</span> <span>16</span><span>:32:48</span> <span>localhost.localdomain</span> <span>systemd[1]:</span> <span>Starting</span> <span>DM</span> <span>database</span> <span>instance</span> <span>service...</span><span>3</span><span>月</span> <span>22</span> <span>16</span><span>:33:05</span> <span>localhost.localdomain</span> <span>DmServiceDMSERVER[6837]:</span> <span>[39B</span> <span>blob</span> <span>data]</span><span>3</span><span>月</span> <span>22</span> <span>16</span><span>:33:05</span> <span>localhost.localdomain</span> <span>systemd[1]:</span> <span>Started</span> <span>DM</span> <span>database</span> <span>instance</span> <span>service.</span><span>[root@localhost</span> <span>~]#</span> 

方法 6：使用 lsof 命令

lsof 能够列出打开的文件，并列出系统上被进程打开的文件的相关信息。

<span>[root@localhost ~]</span># <span>lsof</span> <span>-i</span><span>:5236</span><span>COMMAND</span>   <span>PID</span>  <span>USER</span>   <span>FD</span>   <span>TYPE</span> <span>DEVICE</span> <span>SIZE</span>/<span>OFF</span> <span>NODE</span> <span>NAME</span><span>dmserver</span> <span>7060</span> <span>dmdba</span>    <span>4u</span>  <span>IPv6</span>  <span>46668</span>      <span>0t0</span>  <span>TCP</span> *<span>:padl2sim</span> (LISTEN)

总体来说，进程号和端口号查看的办法虽然很多，但在实际工作中，我们只需要掌握一种自己认为最好用的命令就可以了。后期会根据情况对相关命令进行复盘，详细介绍其用法。