[ERROR] Can't start server: can't check PID filepath: No such file or directory
“强制关机后
mysql（指物理机上部署，非容器）怎么启动不了了？！”
这个报错是由于强制关机导致 mysql pid 文件丢失，查看 mysql 配置文件，找到 pid 文件位置，创建 pid 文件所在的目录并 chown mysql:mysql <目录>即可
[ERROR] Fatal error: Please read "Security" section of the manual to find out how to run mysqld as root
# 指定用户来启动 mysqld
mysqld --user=<USER>
备份脚本例子
#!/bin/bash
mysql_user="xxxx"
mysql_password="xxxx"
mysql_host="xxxx"
mysql_port="xxxx"
backup_dir=/opt/mysql_backup
dt=`date +'%Y%m%d_%H%M'`
echo "Backup Begin Date:" $(date +"%Y-%m-%d %H:%M:%S")
# 备份全部数据库
mysqldump -h$mysql_host -P$mysql_port -u$mysql_user -p$mysql_password -R -E --all-databases --single-transaction > $backup_dir/mysql_backup_$dt.sql
find $backup_dir -mtime +7 -type f -name '*.sql' -exec rm -rf {} \;
echo "Backup Succeed Date:" $(date +"%Y-%m-%d %H:%M:%S")