mysql 啟動失敗：su: warning: cannot change directory to /nonexistent: No such file or directory

 

這種錯誤一般是 mysql 服務器異常關機導致的，解決方案如下：

# Ubuntu
sudo service mysql stop
sudo usermod -d /var/lib/mysql/ mysql
sudo service mysql start

 

# CentOS
sudo systemctl stop mysql.service
sudo usermod -d /var/lib/mysql/ mysql
sudo systemctl start mysql.service