我在服务器上收到此错误（CentOs 7）：
[proxy:debug] proxy_util.c(2209): [client 80.251.245.153:61902] AH00944: connecting fcgi://127.0.0.1/data/webs/dev/index.php to 127.0.0.1:8000
[proxy:debug] proxy_util.c(2246): [client 80.251.245.153:61902] AH02545: fcgi: has determined UDS as /tmp/php56-fpm.sock
[proxy:debug] proxy_util.c(2418): [client 80.251.245.153:61902] AH00947: connected /data/webs/dev/index.php to httpd-UDS:0
[proxy:error] (2)No such file or directory: AH02454: FCGI: attempt to connect to Unix domain socket /tmp/php56-fpm.sock (*) failed
[proxy_fcgi:error] AH01079: failed to make connection to backend: httpd-UDS
[proxy:debug] proxy_util.c(2171): AH00943: FCGI: has released connection for (*)
套接字存在，我尝试将权限更改为 777，但不起作用：
ls -l /tmp/php56-fpm.sock
-rw-rw----. 1 apache apache 0 Feb 17 16:11 …