nginx 负载均衡,后端服务获取不到域名问题

在nginx配置中增加

        location / {
           # include uwsgi_params;
           # uwsgi_pass unix:/home/web/zsh/app_uwsgi.sock;
           proxy_set_header Host $http_host;
           proxy_set_header X-Real-IP $remote_addr;
           proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
           proxy_pass http://127.0.0.1:9991;
        }