node 代码

var express = require('express');
var app = express();
var os = require('os');
var http = require('http');
var cors = require('cors');


app.use(cors());


app.get('/', cors(),function(req, res){  
  var ip = getClientIp(req).match(/\d+\.\d+\.\d+\.\d+/); 
  console.log(ip);
});


function getClientIp(req) {
        return req.headers['x-forwarded-for'] ||
        req.connection.remoteAddress ||
        req.socket.remoteAddress ||
        req.connection.socket.remoteAddress;
}

app.listen(8081);
console.log('listening on port http://localhost:8081/');

nginx 代理

server  {
    listen 80;
    server_name nnn.com;
    
    location / {
        proxy_set_header  X-real-IP $remote_addr;
        proxy_pass      http://127.0.0.1:8081;
    }

       access_log  /home/wwwlogs/nnn.com.log  access;
 }

直接访问服务器的ip 是正常返回客户端的ip

而访问 nginx 代理转向 的域名地址 返回的ip 却是 127.0.01

nginx 转向的 proxy_pass 地址是多少 ，返回的就是多少

node 如何更好的绑定域名呢？