nginx 映射外网环境（内网映射）

upstream tunnel {
  server 127.0.0.1:7689;
server {
  listen 80;
  server_name x.xx.xxx;
  location / {
    proxy_set_header  X-Real-IP  $remote_addr;
    proxy_set_header  X-Forwarded-For $proxy_add_x_forwarded_for;