【nginx】配置x-forwarded-for 头部

原创

wx636dc453ed367 2022-11-11 12:14:26 博主文章分类：nginx ©著作权

文章标签 Ngixn x-forwarded-for 真实ip nginx html 文章分类 运维

©著作权归作者所有：来自51CTO博客作者wx636dc453ed367的原创作品，请联系作者获取转载授权，否则将追究法律责任

本地用tomcat起了一个j2ee的应用，然后又起了一个nginx做反向代理。

nginx.conf：

#user  nobody;
worker_processes  1;

#error_log  logs/error.log;
#error_log  logs/error.log  notice;
#error_log  logs/error.log  info;

#pid        logs/nginx.pid;


events {
    worker_connections  1024;
}


http {
    include       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  logs/access.log  main;

    sendfile        on;
    #tcp_nopush     on;

    #keepalive_timeout  0;
    keepalive_timeout  65;

    #gzip  on;

    server {
        listen       50001;
        server_name  localhost;

        #charset koi8-r;

        #access_log  logs/host.access.log  main;

        location / {
            root   html;
            index  index.html index.htm;
        }

        location /ly {
            proxy_pass   http://127.0.0.1:8080/hello.do;
            proxy_set_header            Host $host;  
            proxy_set_header            X-real-ip $remote_addr;  
            proxy_set_header            X-Forwarded-For $proxy_add_x_forwarded_for;  
        }    

        #error_page  404              /404.html;

        # redirect server error pages to the static page /50x.html
        #
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }
    }
    include servers/*;
}

这里配置了nginx的监听端口为50001。使用了proxy_set_header来配置nginx转发的头部操作。其中如下配置就是针对xff的：

【nginx】配置x-forwarded-for 头部_x-forwarded-for

其中$proxy_add_x_forwarded_for变量的值是当前包的x-forwarded-for变量和remote-addr变量，使用逗号隔开。所以上面的命令就是把当前的包的x-forwarded-for的值设置为x-forwarded-for和remote-addr的连接。这样这个包转发给下游时，下游就有了这台nginx服务器的ip地址。

当client第一次请求nginx服务器时，nginx拿到的x-forwarded-for为null，remote-addr就是client的实际地址，所以第一次的转发的xff值就只有client的ip地址，转发的nginx的地址是在remote-addr里。下一台nginx服务器会把第一台nginx服务器的地址填入xff。所以当一台服务器收到一个包时，上一台服务器的地址并不在xff里面，必须通过remote-addr拿到。

Controller：

public class MainController extends HttpServlet {

    public void doGet(HttpServletRequest request,
                      HttpServletResponse response)
            throws ServletException, IOException
    {
        PrintWriter out = response.getWriter();
        out.println("NGINX FORWARD");
        String ssfAddr = request.getHeader("X-Forwarded-For");

        String realIp = request.getHeader("X-Real-IP");

        String remoteAddr = request.getRemoteAddr();

        System.out.println("X-Forwarded-For: " + ssfAddr);
        System.out.println("X-Real-IP: " + realIp);
        System.out.println("remoteAddr: " + remoteAddr);

    }

}