Nginx反向代理和缓存杂记

反向代理实验

1、准备node1，node2两台节点，node1反向至node2，node2配置wed服务

2、node2启动web服务

3、配置node1的nginx反向代理

3.1 备份配置文件

[root@qq nginx]# cd conf.d/
[root@qq conf.d]# cp default.conf{,.bak}

3.2 node1配置反向代理至后端服务器

[root@qq conf.d]# vim default.conf

location / {
    #root   /usr/share/nginx/html;
    proxy_pass http://10.201.106.22/;

3.3 重载nginx服务

[root@qq conf.d]# service nginx configtest
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful
[root@qq conf.d]# service nginx reload
Reloading nginx:                                           [  OK  ]

3.4 测试访问http://10.201.106.21能够成功跳转至node2的网页

3.5 查看node2访问日志，记录的是Client的IP

[root@ww ~]# tail -1 /var/log/httpd/access_log
10.201.106.1 - - [12/Dec/2016:00:10:31 +0800] "GET /favicon.ico HTTP/1.1" 404 288 "http://10.201.106.22/" "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.106 Safari/537.36"

4、只代理某个请求

4.1 node2节点配置新的网站目录

[root@ww ~]# cd /var/www/html/
[root@ww html]# ls
index.html
[root@ww html]# mkdir bbs
[root@ww html]# vim bbs/index.html

<h1>bbs on node2</h1>

4.2 node1配置反向代理

location / {
    root   /usr/share/nginx/html;
    index  index.html index.htm;
    # example
    #ModSecurityEnabled on;
    #ModSecurityConfig /etc/nginx/modsecurity.conf;
}

location /bbs/ {
    proxy_pass http://10.201.106.22/bbs/;
}

[root@qq conf.d]# service nginx reload
Reloading nginx:                                           [  OK  ]

4.3 访问http://10.201.106.21/bbs/能够跳转到node2的界面

4.4 测试将node1的反向配置，前端改成错误的后再测试

location /qqq/ {
    proxy_pass http://10.201.106.22/bbs/;
}

[root@qq conf.d]# service nginx reload
Reloading nginx:                                           [  OK  ]

测试：http://10.201.106.21/qqq/
可以访问到node2的bbs页面

实际是node1请求的
[root@ww html]# tail -1 /var/log/httpd/access_log
10.201.106.21 - - [12/Dec/2016:02:10:01 +0800] "GET /bbs/ HTTP/1.0" 200 22 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.106 Safari/537.36"

4.5 只有前端，没有后端测试

location /forum/ {
    proxy_pass http://10.201.106.22/;
}

[root@qq conf.d]# service nginx reload
Reloading nginx:                                           [  OK  ]

测试后跳转到主页了，这也是一个URL

4.6 匹配后缀名，跳转

location ~* \.(jpg|png|gif)$ {
    proxy_pass http://10.201.106.22;
}

语法检查：
[root@qq conf.d]# service nginx configtest
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful
[root@qq conf.d]# 

重载服务
[root@qq conf.d]# service nginx reload
Reloading nginx:                                           [  OK  ]
[root@qq conf.d]# 

上传图片到node2节点

访问：http://10.201.106.21/bg.jpg可以访问到node2的图片

4.7 放到目录下的图片访问

上传图片到node2节点；
[root@ww html]# mkdir images
[root@ww html]# cd images/
[root@ww images]# ls
2.jpg
[root@ww images]# 

访问测试，可以看到图片
http://10.201.106.21/images/2.jpg

4.8 修改后端路径，期望放到/images下

location ~* \.(jpg|png|gif)$ {
    proxy_pass http://10.201.106.22/images/;
}

第一种例外
语法错误，模式匹配，后面就不能再跟上URL，连/也不能加
[root@qq conf.d]# service nginx configtest
nginx: [emerg] "proxy_pass" cannot have URI part in location given by regular expression, or inside named location, or inside "if" statement, or inside "limit_except" block in /etc/nginx/conf.d/default.conf:25
nginx: configuration file /etc/nginx/nginx.conf test failed
[root@qq conf.d]# 

4.9 第二种例外，location如果有重写，重写后的结果

发送到后端的值，向后端发送特定首部

1、反向服务器将客户端真实IP发送给node2网站服务器

1.1 node1 配置

[root@qq conf.d]# vim default.conf

location /forum/ {
    proxy_pass http://10.201.106.22/;
    proxy_set_header HOST $host;
    proxy_set_header X-Real-IP $remote_addr;
}

location ~* \.(jpg|png|gif)$ { 
    proxy_pass http://10.201.106.22;
    proxy_set_header X-Real-IP $remote_addr;
}

1.2 服务重载

[root@qq conf.d]# service nginx configtest
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful
[root@qq conf.d]# 
[root@qq conf.d]# service nginx reload
Reloading nginx:                                           [  OK  ]
[root@qq conf.d]# 

1.3 定义node2后端服务器的日志格式

记录日志首部的值
[root@ww images]# vim /etc/httpd/conf/httpd.conf 

#LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\"" combined
LogFormat "%{X-Real-IP}i %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\"" combined

重启服务
[root@ww images]# service httpd restart
Stopping httpd:                                            [  OK  ]
Starting httpd:                                            [  OK  ]
[root@ww images]# 

1.4 更改日志格式后，相比前两条，最后两条的访问日志记录已经变成真正的客户端主机IP了

10.201.106.21 - - [12/Dec/2016:06:57:21 +0800] "GET / HTTP/1.0" 304 - "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.106 Safari/537.36"
10.201.106.21 - - [12/Dec/2016:06:57:39 +0800] "GET / HTTP/1.0" 304 - "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.106 Safari/537.36"
10.201.106.1 - - [12/Dec/2016:07:05:37 +0800] "GET / HTTP/1.0" 304 - "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.106 Safari/537.36"
10.201.106.1 - - [12/Dec/2016:07:05:38 +0800] "GET / HTTP/1.0" 304 - "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.106 Safari/537.36"
[root@ww images]# 

Nginx缓存

1、定义node1节点缓存配置，1条命令

[root@node1 ~]# cd /etc/nginx/
[root@node1 nginx]# vim nginx.conf

http {
    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;

    log_format  main  ‘$remote_addr - $remote_user [$time_local] "$request" ‘
                      ‘$status $body_bytes_sent "$http_referer" ‘
                      ‘"$http_user_agent" "$http_x_forwarded_for"‘;

    access_log  /var/log/nginx/access.log  main;

    proxy_cache_path /cache/nginx/ levels=1:1 keys_zone=mycache:32m;

    sendfile        on;

创建缓存目录，修改权限
[root@node1 nginx]# mkdir -pv /cache/nginx
mkdir: created directory `/cache‘
mkdir: created directory `/cache/nginx‘
[root@node1 nginx]# chown -R nginx:nginx /cache/nginx/
[root@node1 nginx]# 

2、调用缓存

[root@node1 nginx]# vim conf.d/default.conf

location /forum/ {
    proxy_cache mycache;    调用缓存区域
    proxy_cache_valid 200 1d;   200的缓存一天
    proxy_cache_valid 301 302 10m;  301缓存10分钟
    proxy_cache_valid any 1m;   其他缓存1分钟
    proxy_cache_use_stale error timeout http_500 http_502 http_503 http_504;    如果有这些情况，使用旧缓存
    proxy_pass http://10.201.106.22/;
    proxy_set_header HOST $host;
    proxy_set_header X-Real-IP $remote_addr;
}

3、重载服务

[root@node1 nginx]# service nginx configtest
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful
[root@node1 nginx]# 
[root@node1 nginx]# 
[root@node1 nginx]# service nginx reload
Reloading nginx:                                           [  OK  ]
[root@node1 nginx]# 

4、测试

访问网页后，相应缓存目录有产生文件
[root@node1 nginx]# cd /cache/nginx/
[root@node1 nginx]# ls
[root@node1 nginx]# ls
c
[root@node1 nginx]# ls
7  c
[root@node1 nginx]# ls -lht
total 8.0K
drwx------ 3 nginx nginx 4.0K Nov 24 11:21 7
drwx------ 3 nginx nginx 4.0K Nov 24 11:21 c
[root@node1 nginx]# cd 7
[root@node1 7]# ls
c
[root@node1 7]# cd c
[root@node1 c]# ls
99cd97b13b9069e769098b964e66bbc7
[root@node1 c]# ls -lht
total 12K
-rw------- 1 nginx nginx 8.4K Nov 24 11:21 99cd97b13b9069e769098b964e66bbc7
[root@node1 c]# 

缓存后，

Nginx负载均衡

1、关闭缓存

[root@node1 ~]# vim /etc/nginx/nginx.conf

#proxy_cache_path /cache/nginx/ levels=1:1 keys_zone=mycache:32m;

2、定义第三个节点的网页

[root@master1 ~]# vim /var/www/html/index.htm 

<h1>nginx on node3</h1>

3、编辑前端配置

全局配置
[root@node1 ~]# vim /etc/nginx/nginx.conf

    upstream upservers {
        server 10.201.106.22;
        server 10.201.106.130;

    }

web配置

[root@node1 ~]# vim /etc/nginx/conf.d/default.conf

location /forum/ {

proxy_pass http://upservers/;

}

4、 访问http://10.201.106.21/forum/已经可以在两个节点中切换

5、修改负载后端的某台主机权重

[root@node1 ~]# vim /etc/nginx/nginx.conf

    upstream upservers {
        server 10.201.106.22; weight=2;
        server 10.201.106.130;

    }

6、访问网页，22访问2次，130才访问一次

7、

[root@node1 ~]# vim /etc/nginx/nginx.conf

upstream upservers {
    ip_hash;
    server 10.201.106.22 weight=2;
    server 10.201.106.130;

}

8、

upstream upservers {
    server 10.201.106.22 max_fails=2 fail_timeout=1;
    server 10.201.106.130 max_fails=2 fail_timeout=1;

}

将其中一个节点关系服务
[root@node2 ~]# service httpd stop
Stopping httpd:                                            [  OK  ]

测试后：只会在好的节点访问了

重新打开服务后，又能在两个节点间切换了；

9、标记为备用节点

upstream upservers {
    server 10.201.106.22 max_fails=2 fail_timeout=1;
    server 10.201.106.130 max_fails=2 fail_timeout=1 backup;

}

10、

Nginx反向代理和缓存杂记

原文：http://blog.51cto.com/zhongle21/2087740