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MySQL AB复制
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关于MySQL AB复制 本文讲解如何快速打包和安装MySQL， MySQL AB复制，MySQL AB双向复制，MySQL多级主从复制，解决AB双向复制主键冲突。 首先我们先介绍什么是MySQL AB复制。 AB复制又称主从复制，实现的是数据同步。如果要做MySQL AB复制，数据库版本尽量保
关于MySQL AB复制
本文讲解如何快速打包和安装MySQL， MySQL AB复制，MySQL AB双向复制，MySQL多级主从复制，解决AB双向复制主键冲突。
首先我们先介绍什么是MySQL AB复制。
AB复制又称主从复制，实现的是数据同步。如果要做MySQL AB复制，数据库版本尽量保持一致。如果版本不一致，从服务器版本高于主服务器，但是版本不一致不能做双向复制。MySQL AB复制有什么好处呢？有两点，第一是解决宕机带来的数据不一致，因为MySQL AB复制可以实时备份数据；第二点是减轻数据库服务器压力，这点很容易想到，多台服务器的性能一般比单台要好。但是MySQL AB复制不适用于大数据量，如果是大数据环境，推荐使用集群。
然后我们来看看MySQL复制的 3 个主要步骤：
1)主服务器把数据更改记录到二进制日志中，这个操作叫做二进制日志事件；
2)从服务器把主服务器的二进制日志事件拷贝到自己的中继日志（relay log）中；
3)从服务器执行中继日志中的事件，把更改应用到自己的数据上。
快速打包和安装MySQL
在正式介绍MySQL AB复制之前，介绍怎样打包MySQL和快速安装MySQL。
第二步，打包[root@serv08 ~]# find /usr/local/mysql/ /etc/my.cnf /etc/init.d/mysqld > mysqlCopy after login
第三步，拷贝文件到实体机[root@serv08 ~]# tar -cPvzf mysql-5.5.29-linux2.6-x86_64.tar.gz -T mysql [root@serv08 ~]# ll -h total 202M -rw-r--r--. 1 root root 411K Oct 5 19:19 mysql -rw-r--r--. 1 root root 202M Oct 5 19:21 mysql-5.5.29-linux2.6-x86_64.tar.gzCopy after login
第四步，拷贝文件到serv01[root@serv08 mysql]# scp mysql-5.5.29-linux2.6-x86_64.tar.gz 192.168.1.1:/home/Wentasy/software/Copy after login
第五步，解压[root@serv01 ~]# yum install /usr/bin/scp -y [root@larrywen 1005]# scp /home/Wentasy/software/mysql-5.5.29-linux2.6-x86_64.tar.gz 192.168.1.11:/opt root@192.168.1.11's password: mysql-5.5.29-linux2.6-x86_64.tar.gz 100% 201MB 33.5MB/s 00:06Copy after login
第六步，创建组和用户，注意编号和安装好数据库的机器上的用户一致[root@serv01 opt]# tar -xPvf mysql-5.5.29-linux2.6-x86_64.tar.gzCopy after login
第七步，改变MySQL安装目录的拥有者和所属组[root@serv01 opt]# groupadd -g 500 mysql [root@serv01 opt]# useradd -u 500 -g 500 -r -M -s /sbin/nologin mysql [root@serv01 opt]# id mysql uid=500(mysql) gid=500(mysql) groups=500(mysql)Copy after login
第八步，启动MySQL，做测试[root@serv01 opt]# chown mysql.mysql /usr/local/mysql/ -RCopy after login
[root@serv01 opt]# /etc/init.d/mysqld start Starting MySQL.. SUCCESS! [root@serv01 opt]# mysql -bash: mysql: command not found [root@serv01 opt]# vim ~/.bash_profile [root@serv01 opt]# . !$ . ~/.bash_profile [root@serv01 opt]# mysql Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 1 Server version: 5.5.29-log Source distribution Copyright (c) 2000, 2012, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. mysql>Copy after login
MySQL AB单向复制
好了，相信读者已经学会怎样打包MySQL和快速安装MySQL，接下来正式进入主题，我们先来看看一主多从架构的拓扑图：
图一 一主多从架构
该图展示了一个 master 复制多个 slave 的架构，多个 slave 和单个 slave 的实施并没有实质性的区别，在 master 端并不在乎有多少个 slave 连接自己，只要有 slave 的 IO 线程通过了连接认证，向他请求指定位置之后的 binary log 信息，他就会按照该 IO 线程的要球，读取自己的binary log 信息，返回给 slave的 IO 线程。
既然对拓扑图和原理有所了解，我们做一个实验，介绍如何使用MySQL AB复制：
实验环境介绍
主机 IP地址 主机名 备注
serv01： 192.168.1.11 serv01.host.com master
serv08： 192.168.1.18 serv08.host.com slave01
操作系统版本：rhel server 6.1
所需要的软件包：mysql-5.5.29-linux2.6-x86_64.tar.gz
第一步，主服务器创建用户并清空日志
第二步，修改从服务器的server-idmysql> show privileges; mysql> grant replication client, replication slave on *.* to 'larry'@'192.168.1.%' identified by 'larry'; Query OK, 0 rows affected (0.00 sec) mysql> show binary logs; +------------------+-----------+ | Log_name | File_size | +------------------+-----------+ | mysql-bin.000001 | 27320 | | mysql-bin.000002 | 1035309 | | mysql-bin.000003 | 126 | | mysql-bin.000004 | 279 | +------------------+-----------+ 4 rows in set (0.00 sec) mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | mysql | | performance_schema | | test | +--------------------+ 4 rows in set (0.01 sec) mysql> reset master; Query OK, 0 rows affected (0.02 sec) mysql> show binary logs; +------------------+-----------+ | Log_name | File_size | +------------------+-----------+ | mysql-bin.000001 | 107 | +------------------+-----------+ 1 row in set (0.00 sec)Copy after login
第三步，从服务器清空日志<span>[root@serv08 ~]# cat /etc/my.cnf | grep server-id server-id = 1 #server-id = 2 [root@serv08 ~]# vim /etc/my.cnf [root@serv08 ~]# cat /etc/my.cnf | grep server-id server-id = 2 #server-id = 2 [root@serv08 ~]# /etc/init.d/mysqld restart Shutting down MySQL... SUCCESS! Starting MySQL.. SUCCESS! </span><span>#可以查看从服务器中的数据文件</span><span> [root@serv08 ~]# cd /usr/local/mysql/data/ [root@serv08 data]# ll total 29752 -rw-rw----. 1 mysql mysql 18874368 Oct 5 19:45 ibdata1 -rw-rw----. 1 mysql mysql 5242880 Oct 5 19:45 ib_logfile0 -rw-rw----. 1 mysql mysql 5242880 Oct 5 18:16 ib_logfile1 drwxr-xr-x. 2 mysql mysql 4096 Oct 5 18:15 mysql -rw-rw----. 1 mysql mysql 27320 Oct 5 18:15 mysql-bin.000001 -rw-rw----. 1 mysql mysql 1035309 Oct 5 18:15 mysql-bin.000002 -rw-rw----. 1 mysql mysql 126 Oct 5 18:16 mysql-bin.000003 -rw-rw----. 1 mysql mysql 126 Oct 5 19:45 mysql-bin.000004 -rw-rw----. 1 mysql mysql 107 Oct 5 19:45 mysql-bin.000005 -rw-rw----. 1 mysql mysql 95 Oct 5 19:45 mysql-bin.index drwx------. 2 mysql mysql 4096 Oct 5 18:15 performance_schema -rw-r-----. 1 mysql root 4775 Oct 5 19:45 serv08.host.com.err -rw-rw----. 1 mysql mysql 5 Oct 5 19:45 serv08.host.com.pid drwxr-xr-x. 2 mysql mysql 4096 Oct 5 18:12 test </span>Copy after login
第四步，从服务器通过change master to命令修改设置mysql> show binary logs; ERROR 2006 (HY000): MySQL server has gone away No connection. Trying to reconnect... Connection id: 1 Current database: *** NONE *** +------------------+-----------+ | Log_name | File_size | +------------------+-----------+ | mysql-bin.000001 | 27320 | | mysql-bin.000002 | 1035309 | | mysql-bin.000003 | 126 | | mysql-bin.000004 | 126 | | mysql-bin.000005 | 107 | +------------------+-----------+ 5 rows in set (0.00 sec) mysql> reset master; Query OK, 0 rows affected (0.02 sec) mysql> show binary logs; +------------------+-----------+ | Log_name | File_size | +------------------+-----------+ | mysql-bin.000001 | 107 | +------------------+-----------+ 1 row in set (0.00 sec) mysql> show slave status; Empty set (0.00 sec)Copy after login
第五步，开启slave。<span>mysql> change master to -> master_host='192.168.1.11', -> master_user='larry', -> master_password='larry', -> master_port=3306, -> master_log_file='mysql-bin.000001', -> master_log_pos=107;</span><span> Query OK, 0 rows affected (0.01 sec) </span>Copy after login
第六步，从服务器查看是否和主服务器通信成功。如果出现 Slave_IO_Running和Slave_SQL_Running都是yes，则证明配置成功<span>mysql> show slave status \G; *************************** 1. row *************************** Slave_IO_State: Master_Host: 192.168.1.11 Master_User: larry Master_Port: 3306 Connect_Retry: 60 Master_Log_File: mysql-bin.000001 Read_Master_Log_Pos: 107 Relay_Log_File: serv08-relay-bin.000001 Relay_Log_Pos: 4 Relay_Master_Log_File: mysql-bin.000001 </span><span>Slave_IO_Running: No Slave_SQL_Running: No</span><span> Replicate_Do_DB: Replicate_Ignore_DB: Replicate_Do_Table: Replicate_Ignore_Table: Replicate_Wild_Do_Table: Replicate_Wild_Ignore_Table: Last_Errno: 0 Last_Error: Skip_Counter: 0 Exec_Master_Log_Pos: 107 Relay_Log_Space: 107 Until_Condition: None Until_Log_File: Until_Log_Pos: 0 Master_SSL_Allowed: No Master_SSL_CA_File: Master_SSL_CA_Path: Master_SSL_Cert: Master_SSL_Cipher: Master_SSL_Key: Seconds_Behind_Master: NULL Master_SSL_Verify_Server_Cert: No Last_IO_Errno: 0 Last_IO_Error: Last_SQL_Errno: 0 Last_SQL_Error: Replicate_Ignore_Server_Ids: Master_Server_Id: 0 1 row in set (0.00 sec) ERROR: No query specified mysql> start slave; Query OK, 0 rows affected (0.01 sec) </span>Copy after login
第七步，从服务器查看数据文件的更改<span>mysql> show slave status \G; *************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 192.168.1.11 Master_User: larry Master_Port: 3306 Connect_Retry: 60 Master_Log_File: mysql-bin.000001 Read_Master_Log_Pos: 107 Relay_Log_File: serv08-relay-bin.000002 Relay_Log_Pos: 253 Relay_Master_Log_File: mysql-bin.000001 </span><span> Slave_IO_Running: Yes Slave_SQL_Running: Yes</span><span> Replicate_Do_DB: Replicate_Ignore_DB: Replicate_Do_Table: Replicate_Ignore_Table: Replicate_Wild_Do_Table: Replicate_Wild_Ignore_Table: Last_Errno: 0 Last_Error: Skip_Counter: 0 Exec_Master_Log_Pos: 107 Relay_Log_Space: 410 Until_Condition: None Until_Log_File: Until_Log_Pos: 0 Master_SSL_Allowed: No Master_SSL_CA_File: Master_SSL_CA_Path: Master_SSL_Cert: Master_SSL_Cipher: Master_SSL_Key: Seconds_Behind_Master: 0 Master_SSL_Verify_Server_Cert: No Last_IO_Errno: 0 Last_IO_Error: Last_SQL_Errno: 0 Last_SQL_Error: Replicate_Ignore_Server_Ids: Master_Server_Id: 1 1 row in set (0.00 sec) ERROR: No query specified </span>Copy after login
第八步，测试[root@serv08 data]# ll total 28724 -rw-rw----. 1 mysql mysql 18874368 Oct 5 19:45 ibdata1 -rw-rw----. 1 mysql mysql 5242880 Oct 5 19:45 ib_logfile0 -rw-rw----. 1 mysql mysql 5242880 Oct 5 18:16 ib_logfile1 -rw-rw----. 1 mysql mysql 78 Oct 5 19:49 master.info drwxr-xr-x. 2 mysql mysql 4096 Oct 5 18:15 mysql -rw-rw----. 1 mysql mysql 107 Oct 5 19:45 mysql-bin.000001 -rw-rw----. 1 mysql mysql 19 Oct 5 19:45 mysql-bin.index drwx------. 2 mysql mysql 4096 Oct 5 18:15 performance_schema -rw-rw----. 1 mysql mysql 51 Oct 5 19:49 relay-log.info -rw-r-----. 1 mysql root 5589 Oct 5 19:49 serv08.host.com.err -rw-rw----. 1 mysql mysql 5 Oct 5 19:45 serv08.host.com.pid -rw-rw----. 1 mysql mysql 157 Oct 5 19:49 serv08-relay-bin.000001 -rw-rw----. 1 mysql mysql 253 Oct 5 19:49 serv08-relay-bin.000002 -rw-rw----. 1 mysql mysql 52 Oct 5 19:49 serv08-relay-bin.index drwxr-xr-x. 2 mysql mysql 4096 Oct 5 18:12 test [root@serv08 data]# cat relay-log.info ./serv08-relay-bin.000002 253 mysql-bin.000001 107 [root@serv08 data]# cat master.info 18 mysql-bin.000001 107 192.168.1.11 larry larry 3306Copy after login
第九步，查看进程状态<span>--serv08查看数据库</span><span> mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | mysql | | performance_schema | | test | +--------------------+ 4 rows in set (0.02 sec) </span><span>--serv01创建数据库</span><span> mysql> create database larrydb; Query OK, 1 row affected (0.00 sec) </span><span>--serv01查看数据库</span><span> mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | larrydb | | mysql | | performance_schema | | test | +--------------------+ 5 rows in set (0.01 sec) </span><span>--serv08查看数据库，发现已经同步</span><span> mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | larrydb | | mysql | | performance_schema | | test | +--------------------+ 5 rows in set (0.00 sec) </span><span>--serv01创建表 插入数据</span><span> mysql> use larrydb; Database changed mysql> create table test(id int(11)); Query OK, 0 rows affected (0.00 sec) mysql> insert into test values(1); Query OK, 1 row affected (0.00 sec) </span><span>--serv08查看数据是否同步成功，发现数据已经同步</span><span> mysql> use larrydb; Database changed mysql> show tables; +-------------------+ | Tables_in_larrydb | +-------------------+ | test | +-------------------+ 1 row in set (0.00 sec) mysql> select * from test; +------+ | id | +------+ | 1 | +------+ 1 row in set (0.00 sec) </span>Copy after login
--serv01查看进程状态 mysql> show processlist; +----+-------+--------------------+---------+-------------+------+-----------------------------------------------------------------------+------------------+ | Id | User | Host | db | Command | Time | State | Info | +----+-------+--------------------+---------+-------------+------+-----------------------------------------------------------------------+------------------+ | 1 | root | localhost | larrydb | Query | 0 | NULL | show processlist | | 2 | larry | 192.168.1.18:41393 | NULL | Binlog Dump | 854 | Master has sent all binlog to slave; waiting for binlog to be updated | NULL | +----+-------+--------------------+---------+-------------+------+-----------------------------------------------------------------------+------------------+ 2 rows in set (0.00 sec) --serv08查看进程状态 mysql> show processlist; +----+-------------+-----------+---------+---------+------+-----------------------------------------------------------------------------+------------------+ | Id | User | Host | db | Command | Time | State | Info | +----+-------------+-----------+---------+---------+------+-----------------------------------------------------------------------------+------------------+ | 1 | root | localhost | larrydb | Query | 0 | NULL | show processlist | | 2 | system user | | NULL | Connect | 880 | Waiting for master to send event | NULL | | 3 | system user | | NULL | Connect | 65 | Slave has read all relay log; waiting for the slave I/O thread to update it | NULL | +----+-------------+-----------+---------+---------+------+-----------------------------------------------------------------------------+------------------+ 3 rows in set (0.00 sec)Copy after login
MySQLAB双向复制
好了，MySQL AB单向复制介绍完毕。接下来想想，会有这样的应用场景。比如Master和Slave之间都要进行数据同步，那么单向复制是无法完成的，因为一个是Master，一个是Slave，只能单向操作，这就像网络里的半双工一样。既然一方可以向另一方同步数据，那么两方都做成Master 不就可以实现互相同步数据了。这就是接下来要介绍的MySQL AB双向复制。同样我们来看看MySQL AB双向复制的拓扑图。
图二 MySQL AB双向复制
既然对拓扑图和原理有所了解，我们做一个实验，介绍如何使用MySQL AB双向复制，注意该实验是在MySQL单级复制的基础上做的。
实验环境介绍
主机 IP地址 主机名 备注
serv01： 192.168.1.11 serv01.host.com master
serv08： 192.168.1.18 serv08.host.com slave01
操作系统版本：rhel server 6.1
所需要的软件包：mysql-5.5.29-linux2.6-x86_64.tar.gz
第一步，serv08创建授权用户
第二步，serv08清空日志mysql> grant replication client, replication slave on *.* to 'larry'@'192.168.1.%' identified by 'larry'; Query OK, 0 rows affected (0.01 sec)Copy after login
第三步，serv01使用change master to命令修改从服务器设置mysql> show binary logs; +------------------+-----------+ | Log_name | File_size | +------------------+-----------+ | mysql-bin.000001 | 286 | +------------------+-----------+ 1 row in set (0.00 sec) mysql> reset master; Query OK, 0 rows affected (0.00 sec) mysql> show binary logs; +------------------+-----------+ | Log_name | File_size | +------------------+-----------+ | mysql-bin.000001 | 107 | +------------------+-----------+ 1 row in set (0.00 sec)Copy after login
第四步，serv01开启slavemysql> show slave status; Empty set (0.00 sec) mysql> change master to -> master_host='192.168.1.18', -> master_user='larry', -> master_password='larry', -> master_port=3306, -> master_log_file='mysql-bin.000001', -> master_log_pos=107; Query OK, 0 rows affected (0.01 sec)Copy after login
第五步，测试<span>mysql> start slave; Query OK, 0 rows affected (0.01 sec) mysql> show slave status \G; *************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 192.168.1.18 Master_User: larry Master_Port: 3306 Connect_Retry: 60 Master_Log_File: mysql-bin.000001 Read_Master_Log_Pos: 107 Relay_Log_File: serv01-relay-bin.000002 Relay_Log_Pos: 253 Relay_Master_Log_File: mysql-bin.000001 </span><span> Slave_IO_Running: Yes Slave_SQL_Running: Yes</span><span> Replicate_Do_DB: Replicate_Ignore_DB: Replicate_Do_Table: Replicate_Ignore_Table: Replicate_Wild_Do_Table: Replicate_Wild_Ignore_Table: Last_Errno: 0 Last_Error: Skip_Counter: 0 Exec_Master_Log_Pos: 107 Relay_Log_Space: 410 Until_Condition: None Until_Log_File: Until_Log_Pos: 0 Master_SSL_Allowed: No Master_SSL_CA_File: Master_SSL_CA_Path: Master_SSL_Cert: Master_SSL_Cipher: Master_SSL_Key: Seconds_Behind_Master: 0 Master_SSL_Verify_Server_Cert: No Last_IO_Errno: 0 Last_IO_Error: Last_SQL_Errno: 0 Last_SQL_Error: Replicate_Ignore_Server_Ids: Master_Server_Id: 2 1 row in set (0.00 sec) ERROR: No query specified </span>Copy after login
<span>--serv01查看数据</span><span> mysql> use larrydb; Database changed mysql> select * from test; +------+ | id | +------+ | 1 | +------+ 1 row in set (0.00 sec) </span><span>--serv08插入数据</span><span> mysql> use larrydb; Database changed mysql> select * from test; +------+ | id | +------+ | 1 | +------+ 1 row in set (0.00 sec) mysql> insert into test values(2); Query OK, 1 row affected (0.00 sec) </span><span>--serv01查看数据，数据更新</span><span> mysql> select * from test; +------+ | id | +------+ | 1 | | 2 | +------+ 2 rows in set (0.00 sec) </span><span>--serv01插入数据</span><span> mysql> insert into test values(3); Query OK, 1 row affected (0.01 sec) </span><span>--serv01查询数据</span><span> mysql> select * from test; +------+ | id | +------+ | 1 | | 2 | | 3 | +------+ 3 rows in set (0.00 sec) </span><span>--serv08查询数据，数据已更新</span><span> mysql> select * from test; +------+ | id | +------+ | 1 | | 2 | | 3 | +------+ 3 rows in set (0.00 sec) </span>Copy after login
MySQL多级主从复制
好了，MySQL AB双向复制介绍完毕，我们又想了，不管是MySQL AB单向复制，还是MySQL 双向复制，都是双方的关系。MySQL AB单向复制可以是一对一，也就是一个Master对应一个Slave，或者一对多，也就是一个Master对应多个Slave；MySQL双向复制是一对一的关系。我们可不可以这样，实现多级关系，一个Master，接下来Slave，Slave下面还有Slave。这样做有什么好处呢？这样可以缓解数据库压力。这就是接下来要介绍的MySQL多级主从复制。多级也就是A---->B---->C，A作为主服务器，B是从服务器，B跟A建立主从关系；而且B是主服务器，C作为从服务器，B跟C建立主从关系。这样：A是主服务器，B既是主服务器，又是从服务器，C是从服务器。同样，我们来看看MySQL 多级主从复制的拓扑图：
图三 MySQL 多级主从复制
该拓扑图实现 mysql 的 A 到B 的复制，再从 B 到 C 的复制。
既然对拓扑图和原理有所了解，我们做一个实验，介绍如何使用MySQL AB双向复制：
实验环境介绍
主机 IP地址 主机名 备注
serv01： 192.168.1.11 serv01.host.com master
serv08： 192.168.1.18 serv08.host.com slave01
serv09： 192.168.1.19 serv09.host.com slave02
操作系统版本：rhel server 6.1
所需要的软件包：mysql-5.5.29-linux2.6-x86_64.tar.gz
第一步，断开双向关系。A只作为主服务器。
第二步，serv01重启服务，再次查看slave信息，发现已经不存在<span>--停止slave</span><span> mysql> stop slave; Query OK, 0 rows affected (0.00 sec) </span><span>--查看slave状态发现仍然有相关信息，我们要彻底删除，只需要把数据文件中相关文件删除即可。</span><span> mysql> show slave status \G; *************************** 1. row *************************** Slave_IO_State: Master_Host: 192.168.1.18 Master_User: larry Master_Port: 3306 Connect_Retry: 60 Master_Log_File: mysql-bin.000002 Read_Master_Log_Pos: 587 Relay_Log_File: serv01-relay-bin.000006 Relay_Log_Pos: 733 Relay_Master_Log_File: mysql-bin.000002 Slave_IO_Running: No Slave_SQL_Running: No Replicate_Do_DB: Replicate_Ignore_DB: Replicate_Do_Table: Replicate_Ignore_Table: Replicate_Wild_Do_Table: Replicate_Wild_Ignore_Table: Last_Errno: 0 Last_Error: Skip_Counter: 0 Exec_Master_Log_Pos: 587 Relay_Log_Space: 1036 Until_Condition: None Until_Log_File: Until_Log_Pos: 0 Master_SSL_Allowed: No Master_SSL_CA_File: Master_SSL_CA_Path: Master_SSL_Cert: Master_SSL_Cipher: Master_SSL_Key: Seconds_Behind_Master: NULL Master_SSL_Verify_Server_Cert: No Last_IO_Errno: 0 Last_IO_Error: Last_SQL_Errno: 0 Last_SQL_Error: Replicate_Ignore_Server_Ids: Master_Server_Id: 2 1 row in set (0.00 sec) ERROR: No query specified </span><span>--进入data目录，删除以下文件：master.info relay-log.info serv01-relay-bin.*</span><span> [root@serv01 ~]# cd /usr/local/mysql/data [root@serv01 data]# ll total 28736 -rw-rw----. 1 mysql mysql 18874368 Oct 5 22:38 ibdata1 -rw-rw----. 1 mysql mysql 5242880 Oct 5 22:38 ib_logfile0 -rw-rw----. 1 mysql mysql 5242880 Oct 5 18:16 ib_logfile1 drwx------. 2 mysql mysql 4096 Oct 5 22:36 larrydb -rw-rw----. 1 mysql mysql 79 Oct 5 23:24 master.info drwxr-xr-x. 2 mysql mysql 4096 Oct 5 18:15 mysql -rw-rw----. 1 mysql mysql 690 Oct 5 22:34 mysql-bin.000001 -rw-rw----. 1 mysql mysql 970 Oct 5 22:38 mysql-bin.000002 -rw-rw----. 1 mysql mysql 38 Oct 5 22:34 mysql-bin.index drwx------. 2 mysql mysql 4096 Oct 5 18:15 performance_schema -rw-rw----. 1 mysql mysql 53 Oct 5 23:24 relay-log.info -rw-r-----. 1 mysql root 5309 Oct 5 23:24 serv01.host.com.err -rw-rw----. 1 mysql mysql 5 Oct 5 22:34 serv01.host.com.pid -rw-rw----. 1 mysql mysql 303 Oct 5 22:35 serv01-relay-bin.000005 -rw-rw----. 1 mysql mysql 733 Oct 5 22:37 serv01-relay-bin.000006 -rw-rw----. 1 mysql mysql 52 Oct 5 22:35 serv01-relay-bin.index -rw-r-----. 1 mysql mysql 2209 Oct 5 18:16 serv08.host.com.err drwxr-xr-x. 2 mysql mysql 4096 Oct 5 18:12 test [root@serv01 data]# rm -rf master.info relay-log.info serv01-relay-bin.* </span>Copy after login
第三步，serv08查看slave状态[root@serv01 data]# /etc/init.d/mysqld restart Shutting down MySQL.... SUCCESS! Starting MySQL.. SUCCESS! [root@serv01 opt]# mysql Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 1 Server version: 5.5.29-log Source distribution mysql> show slave status \G; Empty set (0.00 sec) ERROR: No query specifiedCopy after login
第四步，serv09搭建相同版本的MySQL，修改server-id，启动服务<span>mysql> show slave status \G; *************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 192.168.1.11 Master_User: larry Master_Port: 3306 Connect_Retry: 60 Master_Log_File: mysql-bin.000003 Read_Master_Log_Pos: 107 Relay_Log_File: serv08-relay-bin.000007 Relay_Log_Pos: 253 Relay_Master_Log_File: mysql-bin.000003 Slave_IO_Running: Yes Slave_SQL_Running: Yes Replicate_Do_DB: Replicate_Ignore_DB: Replicate_Do_Table: Replicate_Ignore_Table: Replicate_Wild_Do_Table: Replicate_Wild_Ignore_Table: Last_Errno: 0 Last_Error: Skip_Counter: 0 Exec_Master_Log_Pos: 107 Relay_Log_Space: 556 Until_Condition: None Until_Log_File: Until_Log_Pos: 0 Master_SSL_Allowed: No Master_SSL_CA_File: Master_SSL_CA_Path: Master_SSL_Cert: Master_SSL_Cipher: Master_SSL_Key: Seconds_Behind_Master: 0 Master_SSL_Verify_Server_Cert: No Last_IO_Errno: 0 Last_IO_Error: Last_SQL_Errno: 0 Last_SQL_Error: Replicate_Ignore_Server_Ids: Master_Server_Id: 1 1 row in set (0.00 sec) ERROR: No query specified </span><span>--如果查看slave状态出错，我们重启服务</span><span> [root@serv08 ~]# /etc/init.d/mysqld restart Shutting down MySQL.. SUCCESS! Starting MySQL.. SUCCESS! </span>Copy after login
第五步，serv01插入数据[root@serv09 ~]# vim /etc/my.cnf [root@serv09 ~]# cat /etc/my.cnf | grep server-id server-id = 3 [root@serv09 ~]# /etc/init.d/mysqld start Starting MySQL.. SUCCESS!Copy after login
第六步，serv08查看serv01插入的数据是否记录到日志文件。可以发现，和serv01建立关系的延时日志文件中有相关记录，而主日志文件mysql-bin.000003中没有相关记录mysql> use larrydb; Database changed mysql> select * from t2; +----+---------+ | id | name | +----+---------+ | 1 | larry01 | | 3 | larry02 | | 4 | larry03 | | 6 | larry04 | | 7 | larry05 | +----+---------+ 5 rows in set (0.00 sec) mysql> insert into t2(name) values('larry07'); Query OK, 1 row affected (0.01 sec)Copy after login
第七步，我们要把serv08的数据同步到serv09，因为serv08中的mysql-bin.000003文件没有相关记录，所以不能通过日志文件同步，我们只有先serv08导出数据，然后serv09导入数据，再把log_slave_updates打开[root@serv08 data]# mysqlbinlog serv08-relay-bin.000009 | grep insert -i --color /*!40019 SET @@session.max_insert_delayed_threads=0*/; SET INSERT_ID=9/*!*/; insert into t2(name) values('larry07') [root@serv08 data]# mysqlbinlog mysql-bin.000003 | grep larry07Copy after login
第八步，serv01插入测试数据，我们看到打开这个参数后mysql-bin.000004和serv08-relay-bin.000011都有相关的插入数据的记录<span>--导出数据</span><span> [root@serv08 data]# mysqldump --help --verbose | grep database [root@serv08 data]# mysqldump --databases larrydb > larrydb.sql </span><span>--拷贝数据文件</span><span> [root@serv08 data]# scp larrydb.sql 192.168.1.19:/opt root@192.168.1.19's password: larrydb.sql 100% 2612 2.6KB/s 00:00 </span><span>--serv09导入数据</span><span> mysql> source /opt/larrydb.sql; Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 1 row affected (0.01 sec) Database changed Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 6 rows affected (0.01 sec) Records: 6 Duplicates: 0 Warnings: 0 Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.02 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 3 rows affected (0.00 sec) Records: 3 Duplicates: 0 Warnings: 0 Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) Query OK, 0 rows affected (0.00 sec) mysql> use larrydb; Database changed mysql> show tables; +-------------------+ | Tables_in_larrydb | +-------------------+ | t2 | | test | +-------------------+ 2 rows in set (0.01 sec) mysql> select * from t2; +----+---------+ | id | name | +----+---------+ | 1 | larry01 | | 3 | larry02 | | 4 | larry03 | | 6 | larry04 | | 7 | larry05 | | 9 | larry07 | +----+---------+ 6 rows in set (0.01 sec) </span><span><strong>--serv08修改配置文件，打开log_slave_updates，重启MySQL服务</strong></span><span> mysql> show variables like '%update%'; +-----------------------------------------+-------+ | Variable_name | Value | +-----------------------------------------+-------+ | binlog_direct_non_transactional_updates | OFF | | log_slave_updates | OFF | | low_priority_updates | OFF | | sql_low_priority_updates | OFF | | sql_safe_updates | OFF | +-----------------------------------------+-------+ 5 rows in set (0.00 sec) [root@serv08 data]# vim /etc/my.cnf [root@serv08 data]# cat /etc/my.cnf | grep log_slave_updates log_slave_updates=1 [root@serv08 data]# /etc/init.d/mysqld restart Shutting down MySQL.... SUCCESS! Starting MySQL.. SUCCESS! </span><span>--serv08</span><span> mysql> show variables like "%update%"; +-----------------------------------------+-------+ | Variable_name | Value | +-----------------------------------------+-------+ | binlog_direct_non_transactional_updates | OFF | </span><span>| log_slave_updates | ON |</span><span> | low_priority_updates | OFF | | sql_low_priority_updates | OFF | | sql_safe_updates | OFF | +-----------------------------------------+-------+ 5 rows in set (0.00 sec) </span>Copy after login
第九步，serv08创建授权用户mysql> insert into t2(name) values('larry08'); Query OK, 1 row affected (0.00 sec) mysql> select * from t2; +----+---------+ | id | name | +----+---------+ | 1 | larry01 | | 3 | larry02 | | 4 | larry03 | | 6 | larry04 | | 7 | larry05 | | 9 | larry07 | | 11 | larry08 | +----+---------+ 7 rows in set (0.00 sec) [root@serv08 data]# mysqlbinlog mysql-bin.000004 | grep larry use `larrydb`/*!*/; insert into t2(name) values('larry08') [root@serv08 data]# mysqlbinlog serv08-relay-bin.000011 | grep larry use `larrydb`/*!*/; insert into t2(name) values('larry08')Copy after login
第十步，serv09通过change master to修改slave配置，然后启动slave，查看slave状态，查看数据，发现已经从serv08更新过来mysql> select user,password,host from mysql.user where user='larry'; ERROR 2006 (HY000): MySQL server has gone away No connection. Trying to reconnect... Connection id: 3 Current database: larrydb +-------+-------------------------------------------+-------------+ | user | password | host | +-------+-------------------------------------------+-------------+ | larry | *0CDC8D34246E22649D647DB04E7CCCACAB4368B6 | 192.168.1.% | +-------+-------------------------------------------+-------------+ 1 row in set (0.00 sec) mysql> show binary logs; +------------------+-----------+ | Log_name | File_size | +------------------+-----------+ | mysql-bin.000001 | 1046 | | mysql-bin.000002 | 606 | | mysql-bin.000003 | 126 | | mysql-bin.000004 | 335 | +------------------+-----------+ 4 rows in set (0.00 sec)Copy after login
第十一步，serv01插入数据，可以看到serv08 serv09都已经同步过去了<span>mysql> change master to -> master_host='192.168.1.18', -> master_user='larry', -> master_password='larry', -> master_port=3306, -> master_log_file='mysql-bin.000003', -> master_log_pos=<strong>126</strong>;</span><span> Query OK, 0 rows affected (0.03 sec) mysql> show slave status \G; *************************** 1. row *************************** Slave_IO_State: Master_Host: 192.168.1.18 Master_User: larry Master_Port: 3306 Connect_Retry: 60 Master_Log_File: mysql-bin.000003 Read_Master_Log_Pos: 126 Relay_Log_File: serv09-relay-bin.000001 Relay_Log_Pos: 4 Relay_Master_Log_File: mysql-bin.000003 </span><span> Slave_IO_Running: No Slave_SQL_Running: No</span><span> Replicate_Do_DB: Replicate_Ignore_DB: Replicate_Do_Table: Replicate_Ignore_Table: Replicate_Wild_Do_Table: Replicate_Wild_Ignore_Table: Last_Errno: 0 Last_Error: Skip_Counter: 0 Exec_Master_Log_Pos: 126 Relay_Log_Space: 107 Until_Condition: None Until_Log_File: Until_Log_Pos: 0 Master_SSL_Allowed: No Master_SSL_CA_File: Master_SSL_CA_Path: Master_SSL_Cert: Master_SSL_Cipher: Master_SSL_Key: Seconds_Behind_Master: NULL Master_SSL_Verify_Server_Cert: No Last_IO_Errno: 0 Last_IO_Error: Last_SQL_Errno: 0 Last_SQL_Error: Replicate_Ignore_Server_Ids: Master_Server_Id: 0 1 row in set (0.00 sec) ERROR: No query specified mysql> start slave; Query OK, 0 rows affected (0.01 sec) mysql> show slave status \G; *************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 192.168.1.18 Master_User: larry Master_Port: 3306 Connect_Retry: 60 Master_Log_File: mysql-bin.000004 Read_Master_Log_Pos: 335 Relay_Log_File: serv09-relay-bin.000003 Relay_Log_Pos: 481 Relay_Master_Log_File: mysql-bin.000004 </span><span> Slave_IO_Running: Yes Slave_SQL_Running: Yes</span><span> Replicate_Do_DB: Replicate_Ignore_DB: Replicate_Do_Table: Replicate_Ignore_Table: Replicate_Wild_Do_Table: Replicate_Wild_Ignore_Table: Last_Errno: 0 Last_Error: Skip_Counter: 0 Exec_Master_Log_Pos: 335 Relay_Log_Space: 784 Until_Condition: None Until_Log_File: Until_Log_Pos: 0 Master_SSL_Allowed: No Master_SSL_CA_File: Master_SSL_CA_Path: Master_SSL_Cert: Master_SSL_Cipher: Master_SSL_Key: Seconds_Behind_Master: 0 Master_SSL_Verify_Server_Cert: No Last_IO_Errno: 0 Last_IO_Error: Last_SQL_Errno: 0 Last_SQL_Error: Replicate_Ignore_Server_Ids: Master_Server_Id: 2 1 row in set (0.00 sec) ERROR: No query specified mysql> select * from larrydb.t2; +----+---------+ | id | name | +----+---------+ | 1 | larry01 | | 3 | larry02 | | 4 | larry03 | | 6 | larry04 | | 7 | larry05 | | 9 | larry07 | | 11 | larry08 | +----+---------+ 7 rows in set (0.00 sec) </span>Copy after login
<span>--serv01</span><span> mysql> insert into t2(name) values('larry09'); Query OK, 1 row affected (0.00 sec) mysql> select * from t2; +----+---------+ | id | name | +----+---------+ | 1 | larry01 | | 3 | larry02 | | 4 | larry03 | | 6 | larry04 | | 7 | larry05 | | 9 | larry07 | | 11 | larry08 | | 13 | larry09 | +----+---------+ 8 rows in set (0.00 sec) </span><span>--serv08</span><span> mysql> select * from larrydb.t2; +----+---------+ | id | name | +----+---------+ | 1 | larry01 | | 3 | larry02 | | 4 | larry03 | | 6 | larry04 | | 7 | larry05 | | 9 | larry07 | | 11 | larry08 | | 13 | larry09 | +----+---------+ 8 rows in set (0.00 sec) </span><span>--serv09</span><span> mysql> select * from larrydb.t2; +----+---------+ | id | name | +----+---------+ | 1 | larry01 | | 3 | larry02 | | 4 | larry03 | | 6 | larry04 | | 7 | larry05 | | 9 | larry07 | | 11 | larry08 | | 13 | larry09 | +----+---------+ 8 rows in set (0.00 sec)</span>Copy after login
解决AB双向复制主键冲突
在进行MySQLAB双向复制时，如果一张表的主键是自增的，会出现问题。主服务器和从服务器在插入数据时会发生主键冲突，比如A服务器插入一条数据，id为5，B服务器同步过去，但是B服务器插入数据ID也可能是5，就这会引起主键冲突，导致数据不能插入。因此，我们需要解决这个问题。解决办法是主键间隔设置，通过设置主键步长，比如A（13 5 7），B（2 4 6 8），有几台机器步长就为几。接下来的实验是在MySQLAB双向复制的基础上做的。
第一步，serv08创建测试表，插入数据，查看数据
第二步，serv01查看数据mysql> create table t2(id int auto_increment primary key,name varchar(30)); Query OK, 0 rows affected (0.00 sec) mysql> desc t2; +-------+-------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------+-------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | varchar(30) | YES | | NULL | | +-------+-------------+------+-----+---------+----------------+ 2 rows in set (0.00 sec) mysql> insert into t2(name) values('larry01'); Query OK, 1 row affected (0.00 sec) mysql> insert into t2(name) values('larry02'); Query OK, 1 row affected (0.01 sec) mysql> select * from t2; +----+---------+ | id | name | +----+---------+ | 1 | larry01 | | 2 | larry02 | +----+---------+ 2 rows in set (0.00 sec)Copy after login
第二步，serv01和serv08修改配置文件，并重启服务mysql> select * from t2; +----+---------+ | id | name | +----+---------+ | 1 | larry01 | | 2 | larry02 | +----+---------+ 2 rows in set (0.00 sec) mysql> drop table t2; Query OK, 0 rows affected (0.01 sec)Copy after login
第三步，serv01再次模拟数据<span>[root@serv01 opt]# vim /etc/my.cnf [root@serv01 opt]# cat /etc/my.cnf | grep auto_incre </span><span>auto_increment_increment=2 auto_increment_offset=1</span><span> [root@serv01 opt]# /etc/init.d/mysqld restart Shutting down MySQL.. SUCCESS! Starting MySQL.. SUCCESS! [root@serv08 data]# vim /etc/my.cnf [root@serv08 data]# cat /etc/my.cnf | grep auto_incre </span><span>auto_increment_increment=2 auto_increment_offset=2</span><span> [root@serv08 data]# /etc/init.d/mysqld restart Shutting down MySQL. SUCCESS! Starting MySQL.. SUCCESS! </span>Copy after login
<span>mysql> use larrydb; Database changed mysql> show tables; +-------------------+ | Tables_in_larrydb | +-------------------+ | test | +-------------------+ 1 row in set (0.00 sec) mysql> create table t2(id int(11) primary key auto_increment, name varchar(30)); Query OK, 0 rows affected (0.02 sec) mysql> insert into t2(name) values('larry01'); Query OK, 1 row affected (0.01 sec) mysql> insert into t2(name) values('larry02'); Query OK, 1 row affected (0.00 sec) mysql> select * from t2; +----+---------+ | id | name | +----+---------+ | 1 | larry01 | | 3 | larry02 | +----+---------+ 2 rows in set (0.00 sec) </span><span>--serv08</span><span> mysql> select * from t2; +----+---------+ | id | name | +----+---------+ | 1 | larry01 | | 3 | larry02 | +----+---------+ 2 rows in set (0.00 sec) mysql> insert into t2(name) values('larry03'); Query OK, 1 row affected (0.00 sec) mysql> insert into t2(name) values('larry04'); Query OK, 1 row affected (0.00 sec) mysql> select * from t2; +----+---------+ | id | name | +----+---------+ | 1 | larry01 | | 3 | larry02 | | 4 | larry03 | | 6 | larry04 | +----+---------+ 4 rows in set (0.00 sec) </span><span>--serv01</span><span> mysql> insert into t2(name) values('larry05'); Query OK, 1 row affected (0.00 sec) mysql> select * from t2; +----+---------+ | id | name | +----+---------+ | 1 | larry01 | | 3 | larry02 | | 4 | larry03 | | 6 | larry04 | | 7 | larry05 | +----+---------+ 5 rows in set (0.00 sec) </span><span>--serv08</span><span> mysql> select * from t2; +----+---------+ | id | name | +----+---------+ | 1 | larry01 | | 3 | larry02 | | 4 | larry03 | | 6 | larry04 | | 7 | larry05 | +----+---------+ 5 rows in set (0.00 sec) </span>Copy after login
<span><span>我的邮箱</span></span><span>：</span>wgbno27@163.com <span> <span>新浪微博</span></span><span>：</span>@Wentasy27 <span>微信公众平台</span>：JustOracle（微信号：justoracle） <span>数据库技术交流群</span>：336882565（加群时验证 From CSDN XXX） <span><strong>All is Well</strong></span> <span><strong>2013年10月27日</strong></span> <span><strong>By Larry Wen</strong></span>Copy after login
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