nginx的location、root、alias指令用法和区别

Dear 丶 2022-05-23 04:59 134阅读 0赞

来源：http://www.nginx.cn/4658.html

nginx指定文件路径有两种方式root和alias，指令的使用方法和作用域：  
\[root\]  
语法：root path  
默认值：root html  
配置段：http、server、location、if  
\[alias\]  
语法：alias path  
配置段：location

root与alias主要区别在于nginx如何解释location后面的uri，这会使两者分别以不同的方式将请求映射到服务器文件上。  
root的处理结果是：root路径＋location路径  
alias的处理结果是：使用alias路径替换location路径  
alias是一个目录别名的定义，root则是最上层目录的定义。  
还有一个重要的区别是alias后面必须要用“/”结束，否则会找不到文件的。。。而root则可有可无~~

root实例：

<table style="font-size:12px;border:2px solid rgb(204,204,204);margin:5px 0px 10px;background:rgb(255,255,255);padding:0px;width:auto;border-spacing:0px;table-layout:auto;"> 
 <tbody> 
  <tr style="background:0px center;padding:0px;border-style:none;vertical-align:top;margin:0px;"> 
   <td style="border-width:0px;font-family:Monaco, MonacoRegular, 'Courier New', monospace;vertical-align:top;padding:0px;margin:0px;background:rgb(223,239,255);color:rgb(84,153,222);"> 
    <div style="margin:0px;padding:0px;background:0px center;border:0px;white-space:nowrap;font-size:12px;line-height:15px;"> 
     <div style="margin:0px;padding:0px 5px;font-family:inherit;background:0px center;border:0px;text-align:center;height:inherit;">
       1 
     </div> 
     <div style="margin:0px;padding:0px 5px;font-family:inherit;background:rgb(200,225,250);border:0px;text-align:center;height:inherit;color:rgb(49,124,197);">
       2 
     </div> 
     <div style="margin:0px;padding:0px 5px;font-family:inherit;background:0px center;border:0px;text-align:center;height:inherit;">
       3 
     </div> 
    </div></td> 
   <td style="border-width:0px;background:0px center;width:650px;font-family:Monaco, MonacoRegular, 'Courier New', monospace;vertical-align:top;padding:0px;margin:0px;"> 
    <div style="margin:0px;padding:0px;color:rgb(0,0,0);white-space:pre;background:none;border:none;font-size:12px;line-height:15px;"> 
     <div style="margin:0px;padding:0px 5px;font-family:inherit;background:0px center;border:0px;height:inherit;"> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,78,208);">location</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);"> </span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">^</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">~</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);"> </span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">/</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,78,208);">t</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">/</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);"> </span> 
      <span style="font-family:inherit;height:inherit;color:rgb(51,51,51);">{ </span> 
     </div> 
     <div style="margin:0px;padding:0px 5px;font-family:inherit;border:0px;height:inherit;background:rgb(247,247,247);"> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">&nbsp;&nbsp;&nbsp;&nbsp; </span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,45,122);">root</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);"> </span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">/</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,45,122);">www</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">/</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,45,122);">root</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">/</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,45,122);">html</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">/</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(51,51,51);">;</span> 
     </div> 
     <div style="margin:0px;padding:0px 5px;font-family:inherit;background:0px center;border:0px;height:inherit;"> 
      <span style="font-family:inherit;height:inherit;color:rgb(51,51,51);">}</span> 
     </div> 
    </div></td> 
  </tr> 
 </tbody> 
</table>

如果一个请求的URI是/t/a.html时，web服务器将会返回服务器上的/www/root/html/t/a.html的文件。

alias实例：

<table style="font-size:12px;border:2px solid rgb(204,204,204);margin:5px 0px 10px;background:rgb(255,255,255);padding:0px;width:auto;border-spacing:0px;table-layout:auto;"> 
 <tbody> 
  <tr style="background:0px center;padding:0px;border-style:none;vertical-align:top;margin:0px;"> 
   <td style="border-width:0px;font-family:Monaco, MonacoRegular, 'Courier New', monospace;vertical-align:top;padding:0px;margin:0px;background:rgb(223,239,255);color:rgb(84,153,222);"> 
    <div style="margin:0px;padding:0px;background:0px center;border:0px;white-space:nowrap;font-size:12px;line-height:15px;"> 
     <div style="margin:0px;padding:0px 5px;font-family:inherit;background:0px center;border:0px;text-align:center;height:inherit;">
       1 
     </div> 
     <div style="margin:0px;padding:0px 5px;font-family:inherit;background:rgb(200,225,250);border:0px;text-align:center;height:inherit;color:rgb(49,124,197);">
       2 
     </div> 
     <div style="margin:0px;padding:0px 5px;font-family:inherit;background:0px center;border:0px;text-align:center;height:inherit;">
       3 
     </div> 
    </div></td> 
   <td style="border-width:0px;background:0px center;width:650px;font-family:Monaco, MonacoRegular, 'Courier New', monospace;vertical-align:top;padding:0px;margin:0px;"> 
    <div style="margin:0px;padding:0px;color:rgb(0,0,0);white-space:pre;background:none;border:none;font-size:12px;line-height:15px;"> 
     <div style="margin:0px;padding:0px 5px;font-family:inherit;background:0px center;border:0px;height:inherit;"> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,78,208);">location</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);"> </span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">^</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">~</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);"> </span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">/</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,78,208);">t</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">/</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);"> </span> 
      <span style="font-family:inherit;height:inherit;color:rgb(51,51,51);">{ </span> 
     </div> 
     <div style="margin:0px;padding:0px 5px;font-family:inherit;border:0px;height:inherit;background:rgb(247,247,247);"> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);"> </span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,45,122);">alias</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);"> </span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">/</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,45,122);">www</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">/</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,45,122);">root</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">/</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,45,122);">html</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">/</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,45,122);">new_t</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(0,111,224);">/</span> 
      <span style="font-family:inherit;height:inherit;color:rgb(51,51,51);">;</span> 
     </div> 
     <div style="margin:0px;padding:0px 5px;font-family:inherit;background:0px center;border:0px;height:inherit;"> 
      <span style="font-family:inherit;height:inherit;color:rgb(51,51,51);">}</span> 
     </div> 
    </div></td> 
  </tr> 
 </tbody> 
</table>

如果一个请求的URI是/t/a.html时，web服务器将会返回服务器上的/www/root/html/new\_t/a.html的文件。注意这里是new\_t，因为alias会把location后面配置的路径丢弃掉，把当前匹配到的目录指向到指定的目录。

注意：  
1. 使用alias时，目录名后面一定要加"/"。  
3. alias在使用正则匹配时，必须捕捉要匹配的内容并在指定的内容处使用。  
4. alias只能位于location块中。（root可以不放在location中）