Nginx做缓存

清疚 2021-11-11 04:54 393阅读 0赞

## 查看服务 ##

netstat -lntp|grep 80

## Nginx作为缓存WEB服务 ##

通常情况下缓存是用来减少后端压力, **将压力尽可能的往前推**, 减少后端压力,提高网站并发延时

## `Nginx`代理缓存原理 ##

![1541173-20190726202324949-1082507961.jpg][]

## 缓存配置语法 ##

`proxy_cache`配置语法

Syntax: proxy_cache zone | off;
    Default: proxy_cache off;
    Context: http, server, location
    
    //缓存路径
    Syntax: proxy_cache_path path [levels=levels]
    [use_temp_path=on|off] keys_zone=name:size [inactive=time]
    [max_size=size] [manager_files=number] [manager_sleep=time][manager_threshold=time]
    [loader_files=number] [loader_sleep=time] [loader_threshold=time] [purger=on|off]
    [purger_files=number] [purger_sleep=time] [purger_threshold=time];
    Default: —
    Context: http

缓存过期周期

Syntax: proxy_cache_valid [code ...] time;
    Default: —
    Context: http, server, location
    
    //示例
    proxy_cache_valid 200 302 10m;
    proxy_cache_valid 404   1m;

缓存的维度

Syntax: proxy_cache_key string;
    Default:    proxy_cache_key $scheme$proxy_host$request_uri;
    Context: http, server, location
    
    //示例
    proxy_cache_key "$host$request_uri $cookie_user";
    proxy_cache_key $scheme$proxy_host$uri$is_args$args;

## 缓存配置实践 ##

1.  缓存准备

<table> 
 <thead> 
  <tr> 
   <th>系统</th> 
   <th>服务</th> 
   <th>地址</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>CentOS7.4</td> 
   <td>Nginx Proxy</td> 
   <td>192.168.69.112</td> 
  </tr> 
  <tr> 
   <td>CentOS7.4</td> 
   <td>Nginx Web</td> 
   <td>192.168.69.113</td> 
  </tr> 
 </tbody> 
</table>

1.  web节点准备
    
        //建立相关目录
        [root@nginx ~]# mkdir -p /soft/code{1..3}
        //建立相关html文件
        [root@nginx ~]# for i in {1..3};do echo Code1-Url$i > /soft/code1/url$i.html;done 
        [root@nginx ~]# for i in {1..3};do echo Code2-Url$i > /soft/code2/url$i.html;done
        [root@nginx ~]# for i in {1..3};do echo Code3-Url$i > /soft/code3/url$i.html;done
        
        //配置Nginx
        [root@nginx ~]# cat /etc/nginx/conf.d/web_node.conf 
        server {
                listen 8081;
                root /soft/code1;
                index index.html;
        }
        server {
                listen 8082;
                root /soft/code2;
                index index.html;
        }
        server {
                listen 8083;
                root /soft/code3;
                index index.html;
        }
        
        //检查监听端口
        [root@nginx ~]# netstat -lntp|grep 80
        tcp        0      0 0.0.0.0:8081            0.0.0.0:*               LISTEN      50922/nginx: master 
        tcp        0      0 0.0.0.0:8082            0.0.0.0:*               LISTEN      50922/nginx: master 
        tcp        0      0 0.0.0.0:8083            0.0.0.0:*               LISTEN      50922/nginx: master
2.  代理配置缓存

[root@proxy ~]# mkdir /soft/cache
    [root@proxy ~]# cat /etc/nginx/conf.d/proxy_cache.conf
    upstream cache {
        server 192.168.69.113:8081;
        server 192.168.69.113:8082;
        server 192.168.69.113:8083;
    }
    
    #proxy_cache存放缓存临时文件
    #levels     按照两层目录分级
    #keys_zone  开辟空间名, 10m:开辟空间大小, 1m可存放8000key
    #max_size   控制最大大小, 超过后Nginx会启用淘汰规则
    #inactive   60分钟没有被访问缓存会被清理
    #use_temp_path  临时文件, 会影响性能, 建议关闭
    proxy_cache_path /soft/cache levels=1:2 keys_zone=code_cache:10m max_size=10g inactive=60m use_temp_path=off;
    
    server {
            listen 80;
            server_name 192.168.69.12;
    
    #proxy_cache        开启缓存
    #proxy_cache_valid  状态码200|304的过期为12h, 其余状态码10分钟过期
    #proxy_cache_key    缓存key
    #add_header         增加头信息, 观察客户端respoce是否命中
    #proxy_next_upstream 出现502-504或错误, 会跳过此台服务器访问下台
            location / {
                    proxy_pass http://cache;
                    proxy_cache code_cache;
                    proxy_cache_valid 200 304 12h;
                    proxy_cache_valid any 10m;
                    add_header Nginx-Cache "$upstream_cache_status";
                    proxy_next_upstream error timeout invalid_header http_500 http_502 http_503  http_504;
                    include proxy_params;
            }
    }

1.  客户端测试

//
    [root@nginx ~]# curl -s -I http://192.168.56.11/url3.html|grep "Nginx-Cache"
    Nginx-Cache: MISS
    
    //命中
    [root@nginx ~]# curl -s -I http://192.168.56.11/url3.html|grep "Nginx-Cache"
    Nginx-Cache: HIT

## 缓存清理实践 ##

如何清理`proxy_cache`代理缓存

1.`rm`删除已缓存数据

[root@proxy ~]# rm -rf /soft/cache/*
    [root@proxy ~]# curl -s -I http://192.168.56.11/url3.html|grep "Nginx-Cache"
    Nginx-Cache: MISS

2.通过`ngx_cache_purge`扩展模块清理, 需要编译安装`Nginx`

//建立对应目录
    [root@proxy ~]# mkdir /soft/src
    [root@proxy ~]# cd /soft/src
    
    //下载Nginx包
    [root@proxy ~]# wget http://nginx.org/download/nginx-1.12.2.tar.gz
    [root@proxy ~]# tar xf nginx-1.12.2.tar.gz
    
    //下载ngx_cache_purge
    [root@proxy ~]# wget http://labs.frickle.com/files/ngx_cache_purge-2.3.tar.gz
    [root@proxy ~]# tar xf ngx_cache_purge-2.3.tar.gz
    
    //编译Nginx
    
    [root@nginx src]# cd nginx-1.12.2/ && ./configure \
    --prefix=/server/nginx --add-module=../ngx_cache_purge-2.3 \
    --with-http_stub_status_module --with-http_ssl_module
    [root@nginx src]# make && make install
    
    //需要将上文的缓存proxy_cache.conf文件拷贝至源码包中, 并增加如下内容
            location ~ /purge(/.*) {
                    allow   127.0.0.1;
                    allow   192.168.69.0/24;
                    deny    all;
                    proxy_cache_purge    code_cache $host$1$is_args$args;
            }
    
    //检测配置重新加载
    [root@nginx conf.d]# /server/nginx/sbin/nginx -t
    [root@nginx conf.d]# /server/nginx/sbin/nginx -s reload

使用浏览器访问建立缓存

通过`purge`请求对应的缓存数据

再次刷新就会`404`因为缓存内容已清理

## 部分页面不缓存 ##

指定部分页面不进行`proxy_Cache`缓存

cat proxy_cache.conf 
    upstream cache{
            server 192.168.69.113:8081;
            server 192.168.69.113:8082;
            server 192.168.69.113:8083;
    }
    
    proxy_cache_path /soft/cache levels=1:2 keys_zone=code_cache:10m max_size=10g inactive=60m use_temp_path=off;
    
    server {
            listen 80;
            server_name 192.168.69.112;
            if ($request_uri ~ ^/(url3|login|register|password)) {
                    set $cookie_nocache 1;
            }
    
            location / {
                    proxy_pass http://cache;
                    proxy_cache code_cache;
                    proxy_cache_valid 200 304 12h;
                    proxy_cache_valid any 10m;
                    proxy_cache_key $host$uri$is_args$args;
                    'proxy_no_cache $cookie_nocache $arg_nocache $arg_comment;
                    proxy_no_cache $http_pargma $http_authorization;'
                    add_header Nginx-Cache "$upstream_cache_status";
                    proxy_next_upstream error timeout invalid_header http_500 http_502 http_503  http_504;
                    include proxy_params;
            }
    }
    
    //清理缓存
    [root@nginx ~]# rm -rf /soft/cache/*
    
    //请求测试
    [root@nginx ~]# curl -s -I http://192.168.69.112/url3.html|grep "Nginx-Cache"    
    Nginx-Cache: MISS
    [root@nginx ~]# curl -s -I http://192.168.69.112/url3.html|grep "Nginx-Cache"
    Nginx-Cache: MISS
    [root@nginx ~]# curl -s -I http://192.168.69.112/url3.html|grep "Nginx-Cache"
    Nginx-Cache: MISS

## 缓存日志记录统计 ##

//修改/etc/nginx/nginx.conf中log_format格式
    log_format  main  '$http_user_agent' '$request_uri' '$remote_addr - $remote_user [$time_local] "$request" '
                          '$status $body_bytes_sent "$http_referer" '
                          '"$http_user_agent" "$http_x_forwarded_for"' '"$upstream_cache_status"';
                          
    //修改proxy_cache.conf, 在server标签新增access日志
        access_log /var/log/nginx/proxy_cache.log main;
        
    
    //使用curl访问, 最后检查日志命令情况
    curl/7.29.0/url3.html192.168.56.183 - - [19/Apr/2018:11:48:43 -0400] "HEAD /url3.html HTTP/1.1" 200 0 "-" "curl/7.29.0" "-""MISS"
    curl/7.29.0/url2.html192.168.56.183 - - [19/Apr/2018:11:48:45 -0400] "HEAD /url2.html HTTP/1.1" 200 0 "-" "curl/7.29.0" "-""HIT"
    curl/7.29.0/url2.html192.168.56.183 - - [19/Apr/2018:11:48:46 -0400] "HEAD /url2.html HTTP/1.1" 200 0 "-" "curl/7.29.0" "-""HIT"

## [Nginx查看命中率][Nginx] ##

转载于:https://www.cnblogs.com/lovestart/p/11252678.html

[1541173-20190726202324949-1082507961.jpg]: /images/20211109/2521e7d7b01346fb9dea7a4d00eab19e.png
[Nginx]: http://www.361way.com/nginx-cache/2665.html