问题描述
当遇到 [emerg] host not found in upstream 错误时，通过配置 resolver 可以解决。
但是今天遇到一个奇怪的问题：
[root@nginx02 ~]# /usr/local/tengine/sbin/nginx -t nginx: [emerg] host not found in upstream "nianhui.dfwsgroup.com" in /usr/local/tengine/conf/virtual_host/nianhui.dfwsgroup.com.conf:15 nginx: configuration file /usr/local/tengine/conf/nginx.conf test failed [root@nginx02 ~]# /usr/local/tengine/sbin/nginx -t nginx: the configuration file /usr/local/tengine/conf/nginx.conf syntax is ok nginx: configuration file /usr/local/tengine/conf/nginx.conf test is successful
我们并没有修改 Nginx 配置，它自己就好了（时间戳为证）
[root@nginx02 ~]# ll /usr/local/tengine/conf/virtual_host/nianhui.dfwsgroup.com.conf -rw-r--r-- 1 root root 810 May 2 2019 /usr/local/tengine/conf/virtual_host/nianhui.dfwsgroup.com.conf [root@nginx02 ~]# ll /usr/local/tengine/conf/nginx.conf -rw-r--r-- 1 root root 2767 May 15 16:33 /usr/local/tengine/conf/nginx.conf
Tengine version: Tengine/2.3.0 (nginx/1.15.9)
问题原因
DNS 服务问题，导致域名无法被解析