Starting MySQL ** mysqld_safe Directory '/var/lib/mysql' for UNIX socket file don't exists

本地虛擬機(CentOS6.8)啟動MySQL(MySQL5.6.35)服務失敗

[root@VMUest ~]# service mysql status
 ERROR! MySQL is not running, but lock file (/var/lock/subsys/mysql) exists
[root@VMUest ~]# rm -f /var/lock/subsys/mysql
[root@VMUest ~]# service mysql status
 ERROR! MySQL is not running
[root@VMUest ~]# service mysql start
Starting MySQL.170331 10:18:30 mysqld_safe Directory '/var/lib/mysql' for UNIX socket file don't exists.
 ERROR! The server quit without updating PID file (/usr/local/mysql/data/VMUest.pid).

前一天就折騰了mysqlsla，今天MySQL就啟動不了。參考修改CentOS6.5主機名引起MySQL5.6.35服務問題里面的方法沒有效果。各種糾結都沒用，最后想起啟動MySQL服務時，會優先在/etc/目錄下查找my.cnf

[root@VMUest ~]# ll /etc/my.cnf
-rw-r--r--. 1 root root 251 Jan 27 05:41 /etc/my.cnf
[root@VMUest ~]# cat /etc/my.cnf
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
user=mysql
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0

[mysqld_safe]
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
[root@VMUest ~]# ll /etc/ |grep my
-rw-r--r--.  1 root root    251 Jan 27 05:41 my.cnf
[root@VMUest ~]# mv /etc/my.cnf /etc/my.cnf.bak

還真有/etc/my.cnf，里面設置有socket=/var/lib/mysql/mysql.sock。我是使用源碼在虛擬機上安裝的MySQL，安裝目錄為/usr/local/mysql/，相關配置文件都保存在此目錄。並且有檢查/etc/my.cnf文件是否存在(存在就將其重命名/刪除)。怎么又冒出來了？是折騰mysqlsla時出來的？

[root@VMUest ~]# service mysql start
Starting MySQL........................................................... SUCCESS! 

把/etc/my.cnf重命名后，MySQL服務順利啟動~