1. 概述与软件说明
1.1 概述
RDS MySQL 使用开源软件 percona-Xtrabackup 对 MySQL 数据库进行备份。需要下载该软件，然后使用该软件进行恢复。
1.2 软件说明
解压软件
RDS的备份文件是一个压缩包，需要先解压出来，才能恢复，这里下载解压工具 rds_backup_extract (sh 文件)，目前只支持 64 位 Linux 系统。
软件使用方式：
bash rds_backup_extract -f backup.tar.gz/back.xb.gz -C directory # -f 指定要解压的备份集文件 # -C 指定解压到的目录；-C 参数是可选的，如果不指定就解压到当前目录，如 bash rds_backup_extract -f backup.tar.gz
注：需要通过 bash 来执行 rds_backup_extract 脚本文件。
恢复软件
恢复软件请下载官方的 Percona-XtraBackup（下载地址：https://www.percona.com/downloads/XtraBackup/）官方提供各种平台的安装包，请根据自己的需要下载。RDS 备份使用的版本是 2.2.9，建议您下载 2.2.9 或更新的版本使用。想要了解工具原理的可以参考官方文档。
2. Step by step说明
2.1 管理控制台中下载备份文件
具体步骤请参考：RDS Linux 平台使用 wget 工具下载备份与日志文件。
下载文件成功后，如下图：
2.2 解压备份文件
解压备份文件前，要先下载好解压工具 rds_backup_extract
解压备份文件：
bash rds_backup_extract -f /home/mysql/backup/hins575175_xtra_20150429091224.tar.gz -C /home/mysql/data
如下图：
查询解压后生成的文件，其中蓝色字体的目录文件为备份生成时 RDS 存在的数据库
2.3 恢复数据文件
解压备份文件前，要先安装好 Percona-XtraBackup 工具。然后执行下面的命令：
innobackupex --defaults-file=/home/mysql/data/backup-my.cnf --apply-log /home/mysql/data
这一步最后如果看到类似如下输出，显示 completed OK，表示执行成功：
2.4 配置文件修改
由于存在的版本问题，请将解压文件 backup-my.cnf 中的 innodb_fast_checksum、innodb_page_size 、innodb_log_block_size 、
innodb_log_checksum_algorithm注释掉，如下图：
2.5 修改文件属主
修改文件属主，并检查文件所属为mysql用户。
chown -R mysql:mysql /home/mysql/data
2.6 启动mysqld进程并且登录验证
启动mysqld进程，并验证启动成功
mysqld_safe --defaults-file=/home/mysql/data/backup-my.cnf --user=mysql --datadir=/home/mysql/data &
客户端登录mysql验证
注意：
恢复完成后，表 mysql.user 中是不包含 RDS 中创建的用户，需要新建。
新建用户前请执行如下 SQL：
delete from mysql.db where user<>'root' and char_length(user)>0; delete from mysql.tables_priv where user<>'root' and char_length(user)>0; flush privileges;
3. 其他问题
因为软件限制，目前恢复只支持 Linux 下进行。Linux下恢复的数据文件，无论 Windows、Linux 操作系统，MySQL 都可以正常使用。
遇到的问题：
解决 libev.so.4()(64bit) is needed by percona-xtrabackup-2.3.4-1.el6.x86_64案例
在mysql主从同步时经常会用到Xtra, XtraBackup可以说是一个相对完美的免费开源数据备份工具，支持在线无锁表同步复制和可并行高效率的安全备份恢复机制相比mysqldump来说优势较大好处多,在RHEL6中安装XtraBackup时会发生缺少依赖包的现象
本案例针对Xtra缺少依赖包的情况进行安装分析解决
1.本实验环境
[root@master ~]# uname -r 2.6.32-573.el6.x86_64 [root@master ~]# cat /etc/redhat-release Red Hat Enterprise Linux Server release 6.7 (Santiago) mysql> select version(); +------------+ | version() | +------------+ | 5.6.28-log | +------------+ 1 row in set (0.00 sec)
2.安装Xtra
进入页面https://www.percona.com/downloads/XtraBackup/LATEST/下载操作系统对应的XtraBackup版本
[root@master ~]# wget https://www.percona.com/downloads/XtraBackup/Percona-XtraBackup-2.3.4/binary/redhat/6/x86_64/Percona-XtraBackup-2.3.4-re80c779-el6-x86_64-bundle.tar --2016-05-17 12:42:14-- https://www.percona.com/downloads/XtraBackup/Percona-XtraBackup-2.3.4/binary/redhat/6/x86_64/Percona-XtraBackup-2.3.4-re80c779-el6-x86_64-bundle.tar Resolving www.percona.com... 74.121.199.234 Connecting to www.percona.com|74.121.199.234|:443... connected. HTTP request sent, awaiting response... 200 OK Length: 27504640 (26M) [application/x-tar] Saving to: “Percona-XtraBackup-2.3.4-re80c779-el6-x86_64-bundle.tar” 100%[===============================================================================================================>] 27,504,640 2.09M/s in 16s 2016-05-17 12:42:32 (1.62 MB/s) - “Percona-XtraBackup-2.3.4-re80c779-el6-x86_64-bundle.tar” saved [27504640/27504640]
下载完成后进行解压
[root@master ~]# tar xf Percona-XtraBackup-2.3.4-re80c779-el6-x86_64-bundle.tar [root@master ~]# ll total 53764 -rw-------. 1 root root 2103 May 13 01:35 anaconda-ks.cfg -rw-r--r--. 1 root root 30419 May 13 01:35 install.log -rw-r--r--. 1 root root 7927 May 13 01:32 install.log.syslog -rw-rw-r-- 1 root root 5701116 Mar 15 01:03 percona-xtrabackup-2.3.4-1.el6.x86_64.rpm -rw-r--r-- 1 root root 27504640 Mar 17 19:32 Percona-XtraBackup-2.3.4-re80c779-el6-x86_64-bundle.tar -rw-rw-r-- 1 root root 20820820 Mar 15 01:03 percona-xtrabackup-debuginfo-2.3.4-1.el6.x86_64.rpm -rw-rw-r-- 1 root root 974656 Mar 15 01:03 percona-xtrabackup-test-2.3.4-1.el6.x86_64.rpm
3.安装排错步骤
3.1 在安装过程中发现缺少依赖包lib和perl,原则上能用yum解决的就优先用yum解决，yum解决不掉的可以用网上的yum源或者自己单独下载rpm包进行安装
[root@master ~]# rpm -ivh percona-xtrabackup-2.3.4-1.el6.x86_64.rpm warning: percona-xtrabackup-2.3.4-1.el6.x86_64.rpm: Header V4 DSA/SHA1 Signature, key ID cd2efd2a: NOKEY error: Failed dependencies: libev.so.4()(64bit) is needed by percona-xtrabackup-2.3.4-1.el6.x86_64 perl(DBD::mysql) is needed by percona-xtrabackup-2.3.4-1.el6.x86_64
3.2 使用本地yum源安装libev与perl-DBI,但libev.so.4安装失败，是由于本地yum源没有该rpm包，我这里使用网上下载的rpm包进行安装
[root@master ~]# yum install libev.so.4 Loaded plugins: aliases, changelog, kabi, presto, product-id, security, subscription-manager, tmprepo, verify, versionlock This system is not registered to Red Hat Subscription Management. You can use subscription-manager to register. Loading support for Red Hat kernel ABI Setting up Install Process file:///yum/Server/repodata/repomd.xml: [Errno 14] Could not open/read file:///yum/Server/repodata/repomd.xml Trying other mirror. No package libev.so.4 available. Error: Nothing to do
3.3 安装perl-DBD-MySQL 成功完成
[root@master ~]# yum install perl-DBD-MySQL Loaded plugins: aliases, changelog, kabi, presto, product-id, security, subscription-manager, tmprepo, verify, versionlock This system is not registered to Red Hat Subscription Management. You can use subscription-manager to register. Loading support for Red Hat kernel ABI Setting up Install Process Resolving Dependencies --> Running transaction check ---> Package perl-DBD-MySQL.x86_64 0:4.013-3.el6 will be installed --> Processing Dependency: perl(DBI) for package: perl-DBD-MySQL-4.013-3.el6.x86_64 --> Processing Dependency: perl(DBI::Const::GetInfoType) for package: perl-DBD-MySQL-4.013-3.el6.x86_64 --> Running transaction check ---> Package perl-DBI.x86_64 0:1.609-4.el6 will be installed --> Finished Dependency Resolution Dependencies Resolved ========================================================================================================================================================= Package Arch Version Repository Size ========================================================================================================================================================= Installing: perl-DBD-MySQL x86_64 4.013-3.el6 rhel-source 134 k Installing for dependencies: perl-DBI x86_64 1.609-4.el6 rhel-source 707 k Transaction Summary ========================================================================================================================================================= Install 2 Package(s) Total download size: 841 k Installed size: 2.0 M Is this ok [y/N]: y Downloading Packages: Setting up and reading Presto delta metadata Processing delta metadata Package(s) data still to download: 841 k --------------------------------------------------------------------------------------------------------------------------------------------------------- Total 3.6 MB/s | 841 kB 00:00 Running rpm_check_debug Running Transaction Test Transaction Test Succeeded Running Transaction Installing : perl-DBI-1.609-4.el6.x86_64 1/2 Installing : perl-DBD-MySQL-4.013-3.el6.x86_64 2/2 rhel-source/productid | 1.6 kB 00:00 ... Verifying : perl-DBD-MySQL-4.013-3.el6.x86_64 1/2 Verifying : perl-DBI-1.609-4.el6.x86_64 2/2 Installed: perl-DBD-MySQL.x86_64 0:4.013-3.el6 Dependency Installed: perl-DBI.x86_64 0:1.609-4.el6 Complete! [root@master ~]# rpm -ivh percona-xtrabackup-2.3.4-1.el6.x86_64.rpm warning: percona-xtrabackup-2.3.4-1.el6.x86_64.rpm: Header V4 DSA/SHA1 Signature, key ID cd2efd2a: NOKEY error: Failed dependencies: libev.so.4()(64bit) is needed by percona-xtrabackup-2.3.4-1.el6.x86_64
3.4 安装libev包
到http://rpmfind.net/linux/rpm2html/search.php?query=libev.so.4%28%29%2864bit%29&submit=Search+...&system=&arch= 下载操作系统对应的libev包，注意系统号与版本位数
[root@master ~]# wget ftp://rpmfind.net/linux/dag/redhat/el6/en/x86_64/dag/RPMS/libev-4.15-1.el6.rf.x86_64.rpm --2016-05-17 12:54:43-- ftp://rpmfind.net/linux/dag/redhat/el6/en/x86_64/dag/RPMS/libev-4.15-1.el6.rf.x86_64.rpm => “libev-4.15-1.el6.rf.x86_64.rpm” Resolving rpmfind.net... 195.220.108.108 Connecting to rpmfind.net|195.220.108.108|:21... connected. Logging in as anonymous ... Logged in! ==> SYST ... done. ==> PWD ... done. ==> TYPE I ... done. ==> CWD (1) /linux/dag/redhat/el6/en/x86_64/dag/RPMS ... done. ==> SIZE libev-4.15-1.el6.rf.x86_64.rpm ... 74692 ==> PASV ... done. ==> RETR libev-4.15-1.el6.rf.x86_64.rpm ... done. Length: 74692 (73K) (unauthoritative) 100%[===============================================================================================================>] 74,692 187K/s in 0.4s 2016-05-17 12:54:46 (187 KB/s) - “libev-4.15-1.el6.rf.x86_64.rpm” saved [74692] 安装RHEL6对应的libev-4.15-1.el6.rf.x86_64.rpm包 [root@master ~]# rpm -ivh libev-4.15-1.el6.rf.x86_64.rpm warning: libev-4.15-1.el6.rf.x86_64.rpm: Header V3 DSA/SHA1 Signature, key ID 6b8d79e6: NOKEY Preparing... ########################################### [100%] 1:libev ########################################### [100%]
5.完成安装Xtrabackup
再次安装Xtrabackup包，安装完成
[root@master ~]# rpm -ivh percona-xtrabackup-2.3.4-1.el6.x86_64.rpm warning: percona-xtrabackup-2.3.4-1.el6.x86_64.rpm: Header V4 DSA/SHA1 Signature, key ID cd2efd2a: NOKEY Preparing... ########################################### [100%] 1:percona-xtrabackup ########################################### [100%] [root@master ~]#
6.总结
总体来说，安装Xtra相对简单，注意下载操作系统类型和位数对应正确的rpm包一般不会出错
7. 常用下载地址备注
常用下载地址
libev.so http://rpmfind.net/linux/rpm2html/search.php?query=libev.so.4%28%29%2864bit%29&submit=Search+...&system=&arch=
XtraBackup https://www.percona.com/downloads/XtraBackup/LATEST/