mysql主从备份6.docx

linux系统下实现mysql热备份详细步骤(mysql主从复制)作者： 字体：增加 减小 类型：转载 时间：2013-12-12 我要评论这篇文章主要介绍了linux系统下实现MySQL主从热备份 主从的作用：1.可以当做一种备份方式2.用来实现读写分离，缓解一个数据库的压力MySQL主从备份原理：Mysql的主从复制至少是需要两个Mysql的服务，当然Mysql的服务是可以分布在不同的服务器上，也可以在一台服务器上启动多个服务。如果想配置成为同一台上的话，注意安装的时候，选择两个不同的prefix=路径，同时开启服务器的时候，端口不能相同。(1)首先确保主从服务器上的Mysql版本相同（做主从服务器的原则是，MYSQL版本要相同，如果不能满足，最起码从服务器的MYSQL的版本必须高于主服务器的MYSQL版本 ）(2)在主服务器上,设置一个从数据库的账户,使用REPLICATION SLAVE赋予权限,如:复制代码 代码如下:mysql GRANT REPLICATION SLAVE ON *.* TO slave0019 IDENTIFIED BY123456;Query OK, 0 rows affected (0.13 sec)原理master 上提供binlog ,slave 通过 I/O线程从 master拿取 binlog,并复制到slave的中继日志中slave 通过 SQL线程从 slave的中继日志中读取binlog ,然后解析到slave中主从复制大前提需要master与slave同步，因为笔者的数据库数据量不大，所以无需考虑太多，直接把master上的data复制到了slave上，但是如果是大的数据量，比如像taobao这个的系统实验环境准备：OS： CentOS5.4Mysql:Mysql-5.0.41.tar.gz辅助工具:SSH Secure Shell Client两台测试IP&服务器：复制代码 代码如下:Master Server: /Linux CentOS5.4/MYSQL 5.0Slave Server: /Linux CentOS5.4/MYSQL 5.0安装配置步骤：1、首先在Linux环境下分配好磁盘分区以便留足MySQL数据库的备份空间复制代码 代码如下:rootvps mysql# df -hFilesystem Size Used Avail Use% Mounted on/dev/simfs 30G 2.0G 29G 7% /2、MySQL数据库的安装：1将Mysql-5.0.41.tar.gz通过SSH 工具 上传到Linux系统的home目录下2建立MySQL使用者和群组:复制代码 代码如下:#groupadd mysql#useradd -g mysql mysql3解压缩Mysql-5.0.41.tar.gz源码包复制代码 代码如下:#cd /usr/local/sofrware#tar zxvf Mysql-5.0.41.tar.gz4进入源码目录编译安装复制代码 代码如下:#cd /home/Mysql-5.0.41#./configure -prefix=/usr/local/mysql -with-charset=gbk |注:配置Mysql安装路径并且支持中文#make |注:编译#make install |注:编译安装5替换/etc/f文件,进入源码包,执行命令复制代码 代码如下:#cd /home/Mysql-5.0.41#cp support-files/f /etc/f6完成以上操作以后进行初始化数据库,进入已经安装好的mysql目录复制代码 代码如下:#cd /usr/local/mysql#bin/mysql_install_db -user=mysql |注:-user=mysql 初始化表并且规定用mysql用户7设置给mysql和root用户设定访问权限 我们先进入mysql目录复制代码 代码如下:#cd /usr/local/mysql#chown -R root /usr/local/mysql 注:设定root能访问/usr/local/mysq#chown -R mysql /usr/local/mysql/var 注:设定mysql用户能访问/usr/local/mysql/var#chgrp -R mysql /usr/local/mysql 注:设定mysql组能够访问/usr/local/mysq8启动mysql,进入已经安装好的目录复制代码 代码如下:#cd /usr/local/mysql#bin/mysqld_safe -user=mysql &9修改mysql数据库超级用户root的缺省密码:复制代码 代码如下:/usr/local/mysql/bin/mysqladmin -u root password mysql关闭mysql服务器复制代码 代码如下:cd /usr/local/mysql/bin./mysqladmin -u root -p shutdown10设定开机就启动mysql,进入源码目录下复制代码 代码如下:# cd /home/Mysql-5.0.41# cp support-files/mysql.server /etc/init.d/mysql# chmod +x /etc/init.d/mysql# chkconfig -level 345 mysql on# service mysql restartShutting down MySQL. 确定 Starting MySQL 确定 rootlocalhost mysql#到这里MySQL就装好了。3、配置MySQL5.0的复制（Replication）功能一.将master设置为只读。mysql flush tables with read lock;二.用master中的data文件夹替换slave中的data文件夹比如 用 tar zcvf mysql_data.gz /media/raid10/mysql/3306/data然后 mv mysql_data.gz /media/raid10/htdocs/blog/wordpress/因为我的 /media/raid10/htdocs/blog/wordpress/ 是 Nginx 的主目录所以可以在 slave上，用wget下载这个文件，然后 解压，并覆盖slave上的data文件注意：覆盖之前最好备份源文件三.配置master的f,添加以下内容在mysqld配置段添加如下字段复制代码 代码如下:server-id=1log-bin=/media/raid10/mysql/3306/binlog/binlog /这里写你的binlog绝对路径名binlog-do-db=blog /需要同步的数据库，如果没有本行，即表示同步所有的数据库binlog-ignore-db=mysql /被忽略的数据库这里给出我的f配置文件复制代码 代码如下:clientcharacter-set-server = utf8port = 3306socket = /tmp/mysql.sockmysqldcharacter-set-server = utf8replicate-ignore-db = mysqlreplicate-ignore-db = testreplicate-ignore-db = information_schemauser = mysqlport = 3306socket = /tmp/mysql.sockbasedir = /usr/local/webserver/mysqldatadir = /media/raid10/mysql/3306/datalog-error = /media/raid10/mysql/3306/mysql_error.logpid-file = /media/raid10/mysql/3306/mysql.pidopen_files_limit = 10240back_log = 600max_connections = 5000max_connect_errors = 6000table_cache = 614external-locking = FALSEmax_allowed_packet = 16Msort_buffer_size = 1Mjoin_buffer_size = 1Mthread_cache_size = 300#thread_concurrency = 8query_cache_size = 20Mquery_cache_limit = 2Mquery_cache_min_res_unit = 2kdefault-storage-engine = MyISAMthread_stack = 192Ktransaction_isolation = READ-COMMITTEDtmp_table_size = 20Mmax_heap_table_size = 20Mlong_query_time = 3log-slave-updateslog-bin = /media/raid10/mysql/3306/binlog/binlogbinlog-do-db=blogbinlog-ignore-db=mysqlbinlog_cache_size = 4Mbinlog_format = MIXEDmax_binlog_cache_size = 8Mmax_binlog_size = 20Mrelay-log-index = /media/raid10/mysql/3306/relaylog/relaylogrelay-log-info-file = /media/raid10/mysql/3306/relaylog/relaylogrelay-log = /media/raid10/mysql/3306/relaylog/relaylogexpire_logs_days = 30key_buffer_size = 10Mread_buffer_size = 1Mread_rnd_buffer_size = 6Mbulk_insert_buffer_size = 4Mmyisam_sort_buffer_size = 8Mmyisam_max_sort_file_size = 20Mmyisam_repair_threads = 1myisam_recoverinteractive_timeout = 120wait_timeout = 120skip-name-resolve#master-connect-retry = 10slave-skip-errors = 1032,1062,126,1114,1146,1048,1396#master-host = #master-user = username#master-password = password#master-port = 3306server-id = 1innodb_additional_mem_pool_size = 16Minnodb_buffer_pool_size = 20Minnodb_data_file_path = ibdata1:56M:autoextendinnodb_file_io_threads = 4innodb_thread_concurrency = 8innodb_flush_log_at_trx_commit = 2innodb_log_buffer_size = 16Minnodb_log_file_size = 20Minnodb_log_files_in_group = 3innodb_max_dirty_pages_pct = 90innodb_lock_wait_timeout = 120innodb_file_per_table = 0#log-slow-queries = /media/raid10/mysql/3306/slow.log#long_query_time = 10mysqldumpquickmax_allowed_packet = 32M四.在master机上为slave机添加一同步帐号复制代码 代码如下:mysql grant replication slave on *.* to admin15 identified by 12345678;mysql flush privileges ;五.配置slave的f,添加以下内容注意:1.如果mysql是5.5.3-m3 的版本，只需在mysqld字段下添加如下内容server-id=22.如果是5.0x的版本，需要在mysqld字段下添加如下内容复制代码 代码如下:server-id=2log-bin=mysql-bin /这是同步的binlog，具体以你的binlog为准master-host=12master-user=adminmaster-password=12345678master-port=3306master-connect-retry=60 /如果发现主服务器断线，重新连接的时间差；replicate-do-db=blog /同步的数据库，不写本行 表示 同步所有数据库replicate-ignore-db=mysql /不需要备份的数据库log-slave-updateslave-skip-errors我的mysql是5.5.3，这里给出我的slave f配置文件复制代码 代码如下:clientcharacter-set-server = utf8port = 3306socket = /tmp/mysql.sockmysqldcharacter-set-server = utf8replicate-ignore-db = mysqlreplicate-ignore-db = testreplicate-do-db = blogreplicate-ignore-db = information_schemauser = mysqlport = 3306socket = /tmp/mysql.sockbasedir = /usr/local/webserver/mysqldatadir = /media/raid10/mysql/3306/datalog-error = /media/raid10/mysql/3306/mysql_error.logpid-file = /media/raid10/mysql/3306/mysql.pidopen_files_limit = 10240back_log = 600max_connections = 5000max_connect_errors = 6000table_cache = 614external-locking = FALSEmax_allowed_packet = 16Msort_buffer_size = 1Mjoin_buffer_size = 1Mthread_cache_size = 300#thread_concurrency = 8query_cache_size = 20Mquery_cache_limit = 2Mquery_cache_min_res_unit = 2kdefault-storage-engine = MyISAMthread_stack = 192Ktransaction_isolation = READ-COMMITTEDtmp_table_size = 20Mmax_heap_table_size = 20Mlong_query_time = 3log-slave-updateslog-bin = /media/raid10/mysql/3306/binlog/binlogbinlog_cache_size = 4Mbinlog_format = MIXEDmax_binlog_cache_size = 8Mmax_binlog_size = 20Mrelay-log-index = /media/raid10/mysql/3306/relaylog/relaylogrelay-log-info-file = /media/raid10/mysql/3306/relaylog/relaylogrelay-log = /media/raid10/mysql/3306/relaylog/relaylogexpire_logs_days = 30key_buffer_size = 10Mread_buffer_size = 1Mread_rnd_buffer_size = 6Mbulk_insert_buffer_size = 4Mmyisam_sort_buffer_size = 8Mmyisam_max_sort_file_size = 20Mmyisam_repair_threads = 1myisam_recoverinteractive_timeout = 120wait_timeout = 120skip-name-resolve#master-connect-retry = 60slave-skip-errors = 1032,1062,126,1114,1146,1048,1396#master-host=12#master-user = admin#master-password = 12345678#master-port = 3306server-id = 2innodb_additional_mem_pool_size = 16Minnodb_buffer_pool_size = 20Minnodb_data_file_path = ibdata1:56M:autoextendinnodb_file_io_threads = 4innodb_thread_concurrency = 8innodb_flush_log_at_trx_commit = 2innodb_log_buffer_size = 16Minnodb_log_file_size = 20Minnodb_log_files_in_group = 3innodb_max_dirty_pages_pct = 90innodb_lock_wait_timeout = 120innodb_file_per_table = 0#log-slow-queries = /media/raid10/mysql/3306/slow.log#long_query_time = 10mysqldumpquickmax_allowed_packet = 32M六.通过查看master的状态(在master上查看)，为配置slave做准备复制代码 代码如下:mysql show master status/G;ERROR 2006 (HY000): MySQL server has gone awayNo connection. Trying to reconnect.Connection id: 13Current database: blog* 1. row *File: binlog.000005Position: 592Binlog_Do_DB: blogBinlog_Ignore_DB: mysql1 row in set (0.01 sec)ERROR:No query specified从上面的信息，可以看出，master现在使用的binlog是binlog.000005，position是592,那么下面的slave配置必须与这个对应。其实binlog.000005是当前master使用的binlog日志文件position是当前master使用的binlog.000005日志文件的位置简单理解为master正在使用哪个binlog的哪个数据行(位置)。七.如果是5.5.3-m3版本mysql,需要启动slave后，配置与master相关对应的信息(在slave上配置)注意，这个与第六步相对应复制代码 代码如下:mysql stop slave ;mysql change master to master_host=12, master_user=admin, master_password=12345678, master_log_file=binlog.000005, master_log_pos=488;mysql CHANGE MASTER TO MASTER_CONNECT_RETRY=60;这个与5.0的配置f作用是一样的，配置成与master相对应的内容主要是配置slave，让slave知道从master的哪个binlog上的哪个位置复制数据。所以需要知道master的ip,user_name,user_passwd,binlog,binlog_position以及多长时间连接一次master八.开启slave复制代码 代码如下:mysql start slave;九.解除master只读限制,并做测试复制代码 代码如下:mysql unlock tables;mysql use blog;mysql create longxibendi ( a int, b int );十.从slave上查看复制代码 代码如下:mysql use blog;mysql show tables;+-+| Tables_in_blog |+-+| longxibendi | wp_commentmeta | wp_comments | wp_links | wp_options | wp_postmeta | wp_posts | wp_term_relationships | wp_term_taxonomy | wp_terms | wp_usermeta | wp_users |+-+12 rows in set (0.00 sec)可以看到成功了！十一.配置过程中，可以用 show slave status/G; 在 slave上查看 slave的复制情况十二.如果出现什么问题，可能是防火墙的问题/etc/init.d/iptables stop 关闭 master 上的防火墙，或者进行相应的配置常遇到的错误与解决：1.mysqlERROR 2002 (HY000): Cant connect to local MySQL server through socket /var/lib/mysql/mysql.sock (2)这个错误，网上有很多说法，其实直接的原因是mysql服务器没有启动之前我按照5.0x配置master-slave，然后启动slave，在连接slave,就会报这个错误后来发现原因是，mysql slave没有启动起来，然后去查错误日志，发现以下的字段复制代码 代码如下:110505 01:55:20 mysqld_safe mysqld from pid file /media/raid10/mysql/3306/mysql.pid ended110505 02:04:41 mysqld_safe Starting mysqld daemon with databases from /media/raid10/mysql/3306/dataInnoDB: The InnoDB memory heap is disabledInnoDB: Mutexes and rw_locks use InnoDBs own implementation110505 2:04:41 InnoDB: highest supported file format is Barracuda.110505 2:04:41 InnoDB Plugin 1.0.6 started; log sequence number 44338110505 2:04:41 ERROR /usr/local/webserver/mysql/libexec/mysqld: unknown variable master-connect-retry=60110505 2:04:41 ERROR Aborting110505 2:04:41 InnoDB: Starting shutdown.110505 2:04:43 InnoDB: Shutdown completed; log sequence number 44348110505 2:04:43 Note /usr/local/webserver/mysql/libexec/mysqld: Shutdown complete110505 02:04:43 mysqld_safe mysqld from pid file /media/raid10/mysql/3306/mysql.pid ended110505 02:07:44 mysqld_safe Starting mysqld da