原文：http://bash.cyberciti.biz/backup/dump-all-mysql-databases/
一 下载该shell脚本
二 针对你的操作系统环境，修改这个脚本里面的设置
三 把脚本加入crontab里，设定每小时运行shell脚本，例如
# Backup database every 1 hr to /nas
@hourly /root/scripts/db1hr.backup.sh >/dev/null 2>&1
以下是该shell脚本的源代码：
#!/bin/bash
# A simple shell script to backup all MySQL Server Database
# Dump all MySQL database every hour from raid10 db disk to /nas/mysql
# Each dump will be line as follows:
# Directory: /nas/mysql/mm-dd-yyyy
# File: mysql-DBNAME.04-25-2008-14:23:40.gz
# Full path: /nas/mysql/mm-dd-yyyy/mysql-DBNAME.04-25-2008-14:23:40.gz
# -------------------------------------------------------------------------
# Copyright (c) 2005 nixCraft project <http://cyberciti.biz/fb/>
# This script is licensed under GNU GPL version 2.0 or above
# -------------------------------------------------------------------------
# This script is part of nixCraft shell script collection (NSSC)
# Visit http://bash.cyberciti.biz/ for more information.
# -------------------------------------------------------------------------
NOW=$(date +"%m-%d-%Y") # mm-dd-yyyy format
FILE="fs-full-$NOW.tar.gz"
BAK="/nas/mysql/${NOW}"
### Server Setup ###
#* MySQL login user name *#
MUSER="root"
#* MySQL login PASSWORD name *#
MPASS="YOUR-PASSWORD"
#* MySQL login HOST name *#
MHOST="127.0.0.1"
#* MySQL binaries *#
MYSQL="$(which mysql)"
MYSQLDUMP="$(which mysqldump)"
GZIP="$(which gzip)"
# assuming that /nas is mounted via /etc/fstab
if [ ! -d $BAK ]; then
mkdir -p $BAK
else
:
fi
# get all database listing
DBS="$($MYSQL -u $MUSER -h $MHOST -p$MPASS -Bse 'show databases')"
# start to dump database one by one
for db in $DBS
do
FILE=$BAK/mysql-$db.$NOW-$(date +"%T").gz
# gzip compression for each backup file
$MYSQLDUMP -u $MUSER -h $MHOST -p$MPASS $db | $GZIP -9 > $FILE
done |