问题

nginx启动或者重启提示信息如下：

nginx: [emerg] unknown "connection_upgrade" variable
nginx: configuration file /www/server/nginx/conf/nginx.conf test failed

解决方法

在nginx配置文件http标签下添加如下几行：

    map $http_upgrade $connection_upgrade {
           default upgrade;
           ''      close;
       }

Ps：主配置文件yum安装默认路径为/etc/nginx/conf/nginx.conf