# !/bin/sh

dd="$(date +"%Y%m%d%H%M%S")"

# 保存备份个数，备份31天数据

number=31

# 备份保存路径

backup_dir=/var/lib/mysql/beifen

# 将要备份的数据库

database_name=sms

# 如果文件夹不存在则创建

if [ ! -d $backup_dir ];

then

mkdir -p $backup_dir;

fi

# 执行备份命令

/usr/bin/mysqldump --defaults-extra-file=/etc/my.cnf sms >$backup_dir/$database_name-$dd.sql

# 写创建备份日志

echo "create $backup_dir/$database_name-$dd.dupm" >> $backup_dir/log.txt

# 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$number

count=`ls -l -crt $backup_dir/*.sql | awk '{print $9 }' | wc -l`

if [ $count -gt $number ]

then

# 删除最早生成的备份，只保留number数量的备份

rm $delfile

# 写删除文件日志

echo "delete $delfile" >> $backup_dir/log.txt

fi