Mysql实现增量备份步骤

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转载最新推荐文章于 2026-04-21 02:27:54 发布 1w 阅读 AI 写同款· GEO 优化 ›

MySQL全量，增量备份与恢复备份的主要目的是灾难恢复，备份还可以测试应用、回滚数据修改、查询历史数据、审计等。之前已经学习过如何安装MySQL，本小节将从生产运维的角度了解备份恢复的分类与方法。与完全备份不同，增量备份没有重复数据，备份量不大，时间短;但其恢复麻烦，需要上次完全备份及完全备份之后所有的增量备份才能恢复，而且要对所有增量备份进行逐个反推恢复。MySQL没有提供直接的增量备份办法，可以通过MySQL 提供的二进制日志(binarylogs)间接实现增量备份。阅读详情

增量备份

首先在进行增量备份之前需要查看一下配置文件，查看 log_bin 是否开启，因为要做增量备份首先要开启 log_bin 。首先，进入到 myslq 命令行，输入如下命令：

show variables like '%log_bin%';

如下命令所示，则为未开启

# Copyright (c) 2014, 2016, Oracle and/or its affiliates. All rights reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; version 2 of the License.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

#
# The MySQL Server configuration file.
#
# For explanations see
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html

[mysqld]
pid-file = /var/run/mysqld/mysqld.pid
socket = /var/run/mysqld/mysqld.sock
datadir = /var/lib/mysql
#log-error = /var/log/mysql/error.log
# By default we only accept connections from localhost
#bind-address = 127.0.0.1
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0

#binlog setting，开启增量备份的关键
log-bin=/var/lib/mysql/mysql-bin
server-id=123454

修改之后，重启 mysql 服务，输入：

show variables like '%log_bin%';
1
状态如下：

查看当前使用的 mysql_bin.000*** 日志文件，

show master status;
1
状态如下：

当前买国画网站数据库中有如下数据：

mysql> select * from users;
+-------+------+----+
| name | sex | id |
+-------+------+----+
| zone | 0 | 1 |
| zone1 | 1 | 2 |
| zone2 | 0 | 3 |
+-------+------+----+

我们插入一条数据：

insert into `zone`.`users` ( `name`, `sex`, `id`) values ( 'zone3', '0', '4');
1
查看效果：

mysql> select * from users;
+-------+------+----+
| name | sex | id |
+-------+------+----+
| zone | 0 | 1 |
| zone1 | 1 | 2 |
| zone2 | 0 | 3 |
| zone3 | 0 | 4 |
+-------+------+----+

我们执行如下命令，使用新的日志文件：

mysqladmin -uroot -123456 flush-logs
1
日志文件从 mysql-bin.000015 变为 mysql-bin.000016，而 mysql-bin.000015 则记录着刚刚 insert 命令的日志。上句代码的效果如下：

恢复增量备份

那么现在将刚刚插入的数据删除，效果如下：

delete from `zone`.`users` where `id`='4'

mysql> select * from users;
+-------+------+----+
| name | sex | id |
+-------+------+----+
| zone | 0 | 1 |
| zone1 | 1 | 2 |
| zone2 | 0 | 3 |
+-------+------+----+

那么现在就是重点时间了，从 mysql-bin.000015 中恢复数据：

mysqlbinlog /var/lib/mysql/mysql-bin.000015 | mysql -uroot -p123456 zone;
1
上一句代码指定了，需要恢复的 mysql_bin 文件，指定了用户名：root 、密码：123456 、数据库名：zone。效果如下：

mysql> select * from users;
+-------+------+----+
| name | sex | id |
+-------+------+----+
| zone | 0 | 1 |
| zone1 | 1 | 2 |
| zone2 | 0 | 3 |
| zone3 | 0 | 4 |
+-------+------+----+

整一个买国画网站数据库增量备份的操作流程都在这里了，那么我们如何将它写成脚本文件呢，代码如下：

#!/bin/bash
#在使用之前，请提前创建以下各个目录
backupDir=/usr/local/work/backup/daily
#增量备份时复制mysql-bin.00000*的目标目录，提前手动创建这个目录
mysqlDir=/var/lib/mysql
#mysql的数据目录
logFile=/usr/local/work/backup/bak.log
BinFile=/var/lib/mysql/mysql-bin.index
#mysql的index文件路径，放在数据目录下的

mysqladmin -uroot -p123456 flush-logs
#这个是用于产生新的mysql-bin.00000*文件
# wc -l 统计行数
# awk 简单来说awk就是把文件逐行的读入，以空格为默认分隔符将每行切片，切开的部分再进行各种分析处理。
Counter=`wc -l $BinFile |awk '{print $1}'`
NextNum=0
#这个for循环用于比对$Counter,$NextNum这两个值来确定文件是不是存在或最新的
for file in `cat $BinFile`
do
base=`basename $file`
echo $base
#basename用于截取mysql-bin.00000*文件名，去掉./mysql-bin.000005前面的./
NextNum=`expr $NextNum + 1`
if [ $NextNum -eq $Counter ]
then
echo $base skip! >> $logFile
else
dest=$backupDir/$base
if(test -e $dest)
#test -e用于检测目标文件是否存在，存在就写exist!到$logFile去
then
echo $base exist! >> $logFile
else
cp $mysqlDir/$base $backupDir
echo $base copying >> $logFile
fi
fi
done
echo `date +"%Y年%m月%d日 %H:%M:%S"` $Next Bakup succ! >> $logFile