1.缓存常见类型
服务端缓存
代理缓存, 获取服务端内容进行缓存
客户端浏览器缓存
Nginx代理缓存原理
2.缓存配置语法
1.proxy_cache配置语法
Syntax: proxy_cache zone | off; Default: proxy_cache off; Context: http, server, location #1.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 #2.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; #3.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$args;
3.缓存配置实践
1.缓存准备
| 操作系统 | 应用服务 | 外网地址 | 内网地址 |
|---|---|---|---|
| CentOS7.5 | Nginx Proxy | 10.0.0.5 | 172.16.1.5 |
| CentOS7.5 | Nginx Web | 172.16.1.7 |
2.web节点准备
#建立相关目录 [root@web01 ~]# mkdir -p /soft/code{1..3} #建立相关html文件 [root@web01 ~]# for i in {1..3};do echo Code1-Url$i > /soft/code1/url$i.html;done [root@web01 ~]# for i in {1..3};do echo Code2-Url$i > /soft/code2/url$i.html;done [root@web01 ~]# for i in {1..3};do echo Code3-Url$i > /soft/code3/url$i.html;done #配置Nginx [root@web01 ~]# cat /etc/nginx/conf.d/web_node.conf server { listen 8081; root /soft/code1; index index.html; } server { listen 8082; root /soft/code2; index index.html; } server { listen 8083; root /soft/code3; index index.html; } #检查监听端口 [root@web01 ~]# netstat -lntp|grep 80 tcp 0 0 0.0.0.0:8081 0.0.0.0:* LISTEN 50922/nginx: master tcp 0 0 0.0.0.0:8082 0.0.0.0:* LISTEN 50922/nginx: master tcp 0 0 0.0.0.0:8083 0.0.0.0:* LISTEN 50922/nginx: master 3.代理配置缓存
[root@lb01 ~]# mkdir /soft/cache [root@lb01 ~]# cat /etc/nginx/conf.d/proxy_cache.conf upstream cache { server 172.16.1.7:8081; server 172.16.1.7:8082; server 172.16.1.7:8083; } #proxy_cache存放缓存临时文件 #levels 按照两层目录分级 #keys_zone 开辟空间名, 10m:开辟空间大小, 1m可存放8000key #max_size 控制最大大小, 超过后Nginx会启用淘汰规则 #inactive 60分钟没有被访问缓存会被清理 #use_temp_path 临时文件, 会影响性能, 建议关闭 proxy_cache_path /soft/cache levels=1:2 keys_zone=code_cache:10m max_size=10g inactive=60m use_temp_path=off; server { listen 80; server_name cache.bgx.com; #proxy_cache 开启缓存 #proxy_cache_valid 状态码200|304的过期为12h, 其余状态码10分钟过期 #proxy_cache_key 缓存key #add_header 增加头信息, 观察客户端respoce是否命中 #proxy_next_upstream 出现502-504或错误, 会跳过此台服务器访问下台 location / { proxy_pass http://cache; proxy_cache code_cache; proxy_cache_valid 200 304 12h; proxy_cache_valid any 10m; add_header Nginx-Cache "$upstream_cache_status"; proxy_next_upstream error timeout invalid_header http_500 http_502 http_503 http_504; include proxy_params; } } 3.客户端测试
#第一次访问无法命中 [root@lb01 ~]# curl -s -I http://cache.bgx.com/url3.html|grep "Nginx-Cache" Nginx-Cache: MISS #第二次访问命中 [root@lb01 ~]# curl -s -I http://cache.bgx.com/url3.html|grep "Nginx-Cache" Nginx-Cache: HIT
4.缓存如何清理
如何清理proxy_cache代理的缓存
1.使用rm删除已缓存数据
[root@lb01 ~]# rm -rf /soft/cache/* [root@lb01 ~]# curl -s -I http://cache.bgx.com/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@lb01 ~]# mkdir /soft/src [root@lb01 ~]# cd /soft/src #下载Nginx包 [root@lb01 ~]# wget http://nginx.org/download/nginx-1.12.2.tar.gz [root@lb01 ~]# tar xf nginx-1.12.2.tar.gz #下载ngx_cache_purge [root@lb01 ~]# wget http://labs.frickle.com/files/ngx_cache_purge-2.3.tar.gz [root@lb01 ~]# tar xf ngx_cache_purge-2.3.tar.gz #编译Nginx [root@lb01 ~]# 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@lb01 ~]# make && make install
3.增加清理缓存的location，配置如下内容
[root@lb01 ~]# cat /etc/nginx/conf.d/proxy_cache.conf upstream cache { server 172.16.1.7:8081; server 172.16.1.7:8082; server 172.16.1.7:8083; } 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 cache.bgx.com; 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; } } location ~ /purge(/.*) { allow 127.0.0.1; allow 10.0.0.0/24; deny all; proxy_cache_purge code_cache $host$1$is_args$args; } # 检测配置重新加载 [root@nginx conf.d]# /server/nginx/sbin/nginx -t [root@nginx conf.d]# /server/nginx/sbin/nginx -s reload 4.使用浏览器访问建立缓存
5.通过访问purge/url地址，删除对应的缓存
6.再次刷新就会因为缓存内容已清理，而出现404错误
5.指定页面不缓存
1.如何配置指定部分页面不进行proxy_Cache缓存
[root@lb01 ~]# cat /etc/nginx/conf.d/proxy_cache.conf upstream cache{ server 172.16.1.7:8081; server 172.16.1.7:8082; server 172.16.1.7:8083; } proxy_cache_path /soft/cache levels=1:2 keys_zone=code_cache:10m max_size=10g inactive=60m use_temp_path=off; server { listen 80; server_name cache.bgx.com; #如果请求文件如下，则设定nocache为1 if ($request_uri ~ ^/(url3|login|register|password)) { set $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 $nocache $arg_nocache $arg_comment; #不缓存变量为nocache proxy_no_cache $http_pargma $http_authorization; #不缓存http参数以及http认证 add_header Nginx-Cache "$upstream_cache_status"; proxy_next_upstream error timeout invalid_header http_500 http_502 http_503 http_504; include proxy_params; } } #先清理所有缓存 [root@nginx ~]# rm -rf /soft/cache/* #无论如何请求url3都无法命中 [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 6.缓存日志记录
通过日志记录proxy_cache命中情况与对应url
1.修改nginx的log_format格式，增加"$upstream_cache_status"，该变量包含如下几种状态
MISS 未命中，请求被传送到后端
HIT 缓存命中，通过缓存返回数据
EXPIRED 缓存已经过期请求被传送到后端
UPDATING 正在更新缓存，将使用旧的应答
STALE 后端将得到过期的应答
[root@lb01 ~]# vim /etc/nginx/nginx.conf http { log_format main '$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"'; } 2.在server标签中添加对应的access日志
server { ... access_log /var/log/nginx/proxy_cache.log main; ... } 3.使用curl访问, 最后检查日志命令情况
[root@lb01 ~]# tail /var/log/nginx/proxy_cache.log 10.0.0.1 - - [19/Apr/2018:11:48:43 -0400] "HEAD /url3.html HTTP/1.1" 200 0 "-" "curl/7.29.0" "-""MISS" 10.0.0.1 - - [19/Apr/2018:11:48:45 -0400] "HEAD /url2.html HTTP/1.1" 200 0 "-" "curl/7.29.0" "-""HI