通过脚本命令实现数据库定时自动备份

#!/bin/bash
tool=/usr/bin/mysqldump
dd=`date +%Y%m%d`
username=root
password=123456
database=db
backup_count=2
backup_dir=~/mysqlbackup
# 创建备份目录
mkdir -p $backup_dir
#创建备份 mysqldump -u root -p123456 users > /root/mysqlbackup/users-$filename.sql
$tool -u $username -p$password $database > $backup_dir/$database-$dd.sql
#写备份日志
echo "create $backup_dir/$database-$dd.sql" >> $backup_dir/action.log
#找出需要删除的备份
delfile=`ls -l -crt  $backup_dir/*.sql | awk '{print $9 }' | head -1`
#判断现在的备份数量是否大于$backup_count 
count=`ls -l -crt  $backup_dir/*.sql | awk '{print $9 }' | wc -l`
if [ $count -gt $backup_count ]
then
rm $delfile  #删除最早生成的备份，只保留backup_count数量的备份
#写删除文件日志
echo "delete $delfile" >> $backup_dir/action.log
fi

#早上5点执行脚本
crontab -e
0 5 * * * /absolute/path/to/mysqlbak.sh > /dev/null 2>&1 &