衡天主机 提交工单后，帮忙直接 php 切换版本后，armvs.com无法访问。提示：Service Unavailable
The server is temporarily unable to service your request due to maintenance downtime or capacity problems. Please try again later.
https://www.fujieace.com/php/503-service-unavailable.html 这个文章说端口有变化. 百度搜索到得。
衡天客服回复：您好，感谢您的耐心等待，您切换到PHP7.2后网站输出错误如下：
[Thu Jun 25 10:22:19.917261 2020] [proxy_fcgi:error] [pid 28786:tid 140028751607552] [client 172.68.141.219:30492] AH01079: failed to make connection to backend: httpd-UDS
现已为您切换为PHP5.，您可以参考以下链接教程，查看网站的错误日志，并修改您的网站代码，谢谢。
查看错误日志：http://www.hengtian.cc/archives/90.html
我继续查看错误日记：
[Thu Jun 25 03:56:06.963227 2020] [core:error] [pid 14043:tid 139671463884544] (13)Permission denied: [client 172.69.34.89:42190] AH00035: access to /index.php denied (filesystem path '/home/armvscom/domains') because search permissions are missing on a component of the path [Thu Jun 25 04:39:46.628090 2020] [core:error] [pid 15205:tid 139671430313728] (13)Permission denied: [client 36.57.179.149:9339] AH00035: access to /index.php denied (filesystem path '/home/armvscom/domains') because search permissions are missing on a component of the path [Thu Jun 25 08:33:39.870237 2020] [access_compat:error] [pid 12093:tid 139671749236480] [client 37.59.46.228:54863] AH01797: client denied by server configuration: /home/armvscom/domains/armvs.com/public_html/xmlrpc.php, referer: http://www.google.com.hk [Thu Jun 25 09:20:30.678804 2020] [proxy:error] [pid 10877:tid 140028315186944] (2)No such file or directory: AH02454: FCGI: attempt to connect to Unix domain socket /usr/local/php72/sockets/armvscom.sock (*) failed 粗体部分错误 重复出现。剩下waring 之类的 都不用看了。
类似问题搜索到这个博客日记：https://84361749.com/post/errorlog-wordpress-fpm.html 解决方法 ：
# pool.conf
[wordpress]
listen=/opt/php/var/run/wordpress.sock include=/opt/php/etc/common-dynamic.conf include=/opt/apps/wordpress/conf/php-fpm/php-settings.conf include=/opt/php/etc/environment.conf pm=dynamic
发现一行第2个include忘记修改了，更改为正确的路径，重启服务器，又搞定一个错误日志。
继续搜索看看什么时候可以切换到7.2php