第一步检查nginx配置

#the following would go within the server{} block of your web server config
location /socket.io {
        proxy_pass http://websocket; #could be localhost if Echo and NginX are on the same box
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "Upgrade";
    }

如果还有问题就去找运维 检查cdn运营商配置 服务器一些安全相关的配置比如ddos