一、背景介绍
本人有两个vps，一个linode，一个阿里云，其中linode是本博客所在主机，很多资料需要定期备份。恰好阿里云的磁盘够大，整个linode主机磁盘拷贝进去也有富余，于是简单做个增量备份的shell脚本。 在这里献丑了。
二、配置过程
1 配置两个vps的ssh免密码登录
2 两个vps均安装rsync
yum install -y rsync
3 编写备份脚本
备份脚本的内容如下，
#!/bin/bash
# this script is made to automatically backup data of host linode
# Author:Attaboy
# Modify history:
# 2017.11.11
# 2017.11.14 add local backup function
# 2017.11.17 do not print debug info to log file when backup DB
# 2017.11.22 add mailx report
# 2017.11.25 if initial backup size is too low ,then mail to report.
source /etc/profile
switch="0"
src="/data /srv /etc /mnt /opt /media /var/www /usr /lib /lib64 /bin /root /home /sbin /boot /sys"
bak_node1="[email protected]:/data/backup/linode"
bak_node2="/data/backup"
bak_node1_ip="peloo.cn"
bak_node1_port="34782"
bak_log="/var/log/linode-backup.log"
dst_mail="[email protected]"
mail_content_01="\n\nYour aliyun vps sshd service is offline when running backup!!!\n\n"
mail_content_02="\n\nYour disk size is lower than 1500MB after cleaning some files, please release some space !!!\n\n$(df -mT)\n\n"
mail_title_01="Linode Backup Report"
mail_title_02="Linode Running Health Report"
free_disk_size="$(df -m | awk '/sda/{ print $4 }')"
required_disk_size="1500"
pre_do(){
#clean some backup files first.
find ${bak_node2} -type f -ctime +5 -execdir rm -f {} \;
# check the integtity of important paths and remote host alive.
if [ ${UID} -ne 0 ] ; then
echo -e '\n...... Current user is not root, please switch user using "su" .\n' >>${bak_log}
exit -1
elif [ ${free_disk_size} -lt ${required_disk_size} ] ; then
echo -e "\n\nYour disk size is lower than ${required_disk_size}MB after cleaning some files,Please release some space !\n\n" >>${bak_log} 2>&1
echo -e "${mail_content_02}" | mailx -v -s "${mail_title_02}" "${dst_mail}" >>${bak_log} 2>&1
exit -4
else
echo -e "\n\nYour disk size is adiquate !!!\n\n"
fi
}
backup_node1(){
#backup local file to remote node1--aliyun vps
nc -zv ${bak_node1_ip} ${bak_node1_port}
if [ $? -eq 0 -a ${switch} -eq 0 ] ; then
echo -e "\ntime:$(date)...... remote backup node1 begin,just wait .\n" >>${bak_log}
for i in ${src} ; do
echo ${i}
rsync -azvP ${i} -e "ssh -p ${bak_node1_port}" ${bak_node1} >>${bak_log} 2>&1
done
echo -e "\ntime:$(date)...... remote backup node1 end.\n" >>${bak_log}
else
echo -e "\n...... HOST ${bak_node1_ip} is offline, script will halt with exit code -2" >>${bak_log}
echo -e "${mail_content_01}" | mailx -v -s "${mail_title_01}" "${dst_mail}" >>${bak_log} 2>&1
exit -2
fi
}
backup_node2(){
#backup local file to local disk
if [ ${switch} -eq 0 ] ; then
tar zcvf ${bak_node2}/wordpress/wordpress-$(date +%Y%m%d)-bak.tar.gz /var/www/wordpress >>${bak_log} 2>&1
tar zcvf ${bak_node2}/nginx/nginx-$(date +%Y%m%d)-bak.tar.gz /usr/local/openresty >>${bak_log} 2>&1
mysqldump -u root -pv0b2uEvrVmjg17mMzw2M --all-databases > ${bak_node2}/mysql/all_database-$(date +%Y%m%d).bak 1>/dev/null
mysqldump -u root -pv0b2uEvrVmjg17mMzw2M owemeawe_hail > ${bak_node2}/mysql/owemeawe_hail-$(date +%Y%m%d).bak 1>/dev/null
fi
}
post_do(){
find ${bak_node2} -type f -ctime +5 -execdir rm -f {} \;
if [ ${free_disk_size} -lt 500 ] ; then
echo -e "\n\nYour disk size is lower than 500MB after cleaning some files,Please release some space !\n\n" >>${bak_log} 2>&1
echo -e "${mail_content_02}" | mailx -v -s "${mail_title_02}" "${dst_mail}" >>${bak_log} 2>&1
else
echo -e "\n\nYour disk size is adiquate !!!\n\n"
fi
}
pre_do
backup_node2
backup_node1
post_do
exit 0
注解：脚本里主要有两个函数，对应备份的两个过程，pre_do函数用来在备份前检查当前运行脚本的用户是否为root，以及判断日志文件是否超过限定并及时清空日志文件，bak_node1函数是用来实现整个远程备份过程的，核心是用了rsync的ssh加密通道进行增量备份，bak_node2函数用来备份本机重要的程序文件和数据库。
4 添加crontab任务计划
在/etc/crontab文件添加每7天备份一次的任务计划
echo "* * */7 * * root /bin/bash /srv/sh/auto-backup.sh">>/etc/crontab
