安装nginx

1. 添加nginx到yum源

rpm -Uvh http://nginx.org/packages/centos/7/noarch/RPMS/nginx-release-centos-7-0.el7.ngx.noarch.rpm

2. 安装Nginx

yum install -y nginx

3. 启动Nginx

systemctl start nginx

4. CentOS 7 开机启动Nginx

systemctl enable nginx

5. Nginx配置信息

网站文件存放默认目录

/usr/share/nginx/html

网站默认站点配置

/etc/nginx/conf.d/default.conf

自定义Nginx站点配置文件存放目录

/etc/nginx/conf.d/

Nginx全局配置

/etc/nginx/nginx.conf

6. 将NGINX加到SELinux的允许名单
   如果nginx反向代理本机服务，遇到502错误，可以看看是不是SELinux造成的。

查看SELinux状态：
/usr/sbin/sestatus -v ##如果SELinux status参数为enabled即为开启状态
SELinux status: enabled

getenforce ##也可以用这个命令检查

临时关闭/开启（不用重启机器）：

setenforce 0                  ##设置SELinux 成为permissive模式
setenforce 1                 ##设置SELinux 成为enforcing模式

如果关闭SELinux后，反向代理成功的话，就可以判断是SELinux造成的。

把NGINX加入SELinux的允许名单的方法

yum install policycoreutils-python  
cat /var/log/audit/audit.log | grep nginx | grep denied | audit2allow -M mynginx  
semodule -i mynginx.pp  

7. 配置示例

client_max_body_size 500M;
client_body_buffer_size 1024k;
fastcgi_buffer_size 128k;
fastcgi_buffers 256 16k;

    upstream websocket {
        server 192.168.2.106:8280;
    }
    
    upstream eber {
        server 192.168.2.105:8081 max_fails=1 fail_timeout=30s;
        server 192.168.2.106:8081;
    }
    server {
        
        location /websocket {
            proxy_pass http://websocket/websocket;
            
            proxy_redirect    off;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header Host $host;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        
            proxy_http_version 1.1;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection "upgrade";
        }
        
        location /sockjs/websocket {
            proxy_pass http://websocket/sockjs/websocket;
            
            proxy_redirect    off;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header Host $host;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        
            proxy_http_version 1.1;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection "upgrade";
        }
        
        location / {
            proxy_pass http://eber;
            proxy_connect_timeout 3s; #默认值60s, nginx连接到后端服务器的连接超时时间
        }
    }