Mysql5.5配置主从复制

Mysql提供了主从复制的功能，作用类似oracle的dataguard，但是配置和管理远比dataguard简单，没有所谓的物理备库和逻辑备库之分，也没有提供相应的数据保护模式，只有master和slave数据库角色，这种架构广泛应用于各大门户，游戏网站中，提供数据库的读写分离功能；相比之下oracle的读写功能到了11g版本才能借助active dataguard完美实现，否则就只能用logical standby，但又有许多的数据类型和操作不被逻辑备库支持！先前使用过mysql5.1.36版本的master-slave架构做CMS数据库的读写分离，有着非常痛苦的使用经历，经常由于各种各样的原因的导致主从数据不同步，然后又没有提供额外的同步机制(确切的说是没学会)，于是经常在下班时间重构主从架构；下一步将在mysql5.5平台测试mha架构，故本文记录下如何在mysql5.5平台下构建主从数据库复制环境；另外mysql的主从也可看为是mysql的实时备份，有一定的数据灾备功能，mysql本身没有提供类似oracle
rman的热备份工具，因而多数场景下会使用主从对数据库做一个实时备份，以备不时只需！PS：一直比较不解的mysql如何做基于时间或者SCN的不完全恢复？难道真要一个个binlog分析过去？
一：在主库上创建用于复制的账号并在从库上连接测试

[root@dg53 ~]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.5.25-log Source distribution

Copyright (c) 2000, 2011, 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> grant replication slave on *.* to 'r_test'@'192.168.123.14' identified by '123456';
Query OK, 0 rows affected (0.00 sec)

[root@dg54 ~]# mysql -u r_test -h 192.168.123.13 -p
Enter password:
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.5.25-log Source distribution

Copyright (c) 2000, 2011, 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> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| test               |
+--------------------+
2 rows in set (0.01 sec)

二：修改主库my.cnf文件如下，注意红色字体部分，重启数据库实例

[root@dg53 ~]# grep -v '^#' /etc/my.cnf |grep -v '^$'
[client]
port            = 3306
socket          = /tmp/mysql.sock
[mysqld]
port            = 3306
socket          = /tmp/mysql.sock
skip-external-locking
key_buffer_size = 256M
max_allowed_packet = 1M
table_open_cache = 256
sort_buffer_size = 1M
read_buffer_size = 1M
read_rnd_buffer_size = 4M
myisam_sort_buffer_size = 64M
thread_cache_size = 8
query_cache_size= 16M
thread_concurrency = 8
innodb_data_home_dir =
innodb_data_file_path = /dev/raw/raw6:1Graw
log-bin=mysql-bin
binlog_format=mixed
server-id=1
log-bin=mysql-bin
binlog-do-db=bbs
binlog-do-db=test
binlog-ignore-db=mysql
[mysqldump]
quick
max_allowed_packet = 16M
[mysql]
no-auto-rehash
[myisamchk]
key_buffer_size = 128M
sort_buffer_size = 128M
read_buffer = 2M
write_buffer = 2M
[mysqlhotcopy]
interactive-timeout

[root@dg53 ~]# service mysqld restart
Shutting down MySQL.[  OK  ]
Starting MySQL..[  OK  ]

[root@dg53 ~]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.5.25-log Source distribution

Copyright (c) 2000, 2011, 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> show master status;
+------------------+----------+--------------+------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+----------+--------------+------------------+
| mysql-bin.000011 |      107 | bbs,test     | mysql            |
+------------------+----------+--------------+------------------+
1 row in set (0.00 sec)

三：修改从库my.cnf文件如下，注意红色字体部分，重启数据库实例

[root@dg54 ~]# grep -v '^#' /etc/my.cnf |grep -v '^$'
[client]
port            = 3306
socket          = /tmp/mysql.sock
[mysqld]
port            = 3306
socket          = /tmp/mysql.sock
skip-external-locking
key_buffer_size = 256M
max_allowed_packet = 1M
table_open_cache = 256
sort_buffer_size = 1M
read_buffer_size = 1M
read_rnd_buffer_size = 4M
myisam_sort_buffer_size = 64M
thread_cache_size = 8
query_cache_size= 16M
thread_concurrency = 8
innodb_data_home_dir =
innodb_data_file_path = /dev/raw/raw6:1Graw
log-bin=mysql-bin
binlog_format=mixed
server-id       = 2
log-bin=mysql-bin
replicate-do-db=test
replicate-do-db=bbs
[mysqldump]
quick
max_allowed_packet = 16M
[mysql]
no-auto-rehash
[myisamchk]
key_buffer_size = 128M
sort_buffer_size = 128M
read_buffer = 2M
write_buffer = 2M
[mysqlhotcopy]
interactive-timeout

[root@dg54 ~]# service mysqld restart
Shutting down MySQL..[  OK  ]
Starting MySQL..[  OK  ]

四:在从库上指定主库的连接信息，并开启同步进程

[root@dg54 ~]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.5.25-log Source distribution

Copyright (c) 2000, 2011, 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> change master to master_host='192.168.123.13',master_user='r_test',master_password='123456';
Query OK, 0 rows affected (0.07 sec)

mysql> slave start;
Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql> show slave status \G;
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.123.13
Master_User: r_test
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000011
Read_Master_Log_Pos: 107
Relay_Log_File: dg54-relay-bin.000013
Relay_Log_Pos: 253
Relay_Master_Log_File: mysql-bin.000011
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB: test,bbs
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: 554
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

五：验证数据同步结果，在5.1.36版本下，这里还需要在从库建相应的数据库，导入表数据

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| bbs                |
| mysql              |
| performance_schema |
| test               |
+--------------------+
5 rows in set (0.02 sec)

mysql> use bbs;
Database changed
mysql> show tables;
+---------------+
| Tables_in_bbs |
+---------------+
| user          |
+---------------+
1 row in set (0.00 sec)

mysql> select count(*) from user;
+----------+
| count(*) |
+----------+
|      768 |
+----------+
1 row in set (0.01 sec)