nginx: [emerg] directive "upstream" has no opening "{" in /application/nginx-1.6.3/conf/nginx.conf:13 ...

修改nginx.conf配置文件时，报以下错误：

[root@bqh-lb-121 nginx]# vim conf/nginx.conf
[root@bqh-lb-121 nginx]# sbin/nginx -t
nginx: [emerg] directive "upstream" has no opening "{" in /application/nginx-1.6.3/conf/nginx.conf:13
nginx: configuration file /application/nginx-1.6.3/conf/nginx.conf test failed