centos下MySQL主从同步配置
一、环境

        主机：

                   master操作系统：centos 5.3

                   IP：192.168.1.222

                   MySQL版本：5.0.77

         从机：         

     slave操作系统：centos 5.3

                   IP：192.168.1.220

                   MySQL版本：5.0.77

二、创建数据库

分别登录master机和slave机的mysql：mysql –u root –p

创建数据库：create database repl;

三、master机和slave机的相关配置

1、修改master机器中mysql配置文件my.cnf，该文件在/etc目录下

在[mysqld]配置段添加如下字段

server-id=1

log-bin=log

binlog-do-db=repl //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

在master机上为slave机添加一同步帐号
grant replication slave on *.* to ‘repl‘@‘192.1681.220‘ identified by ‘123456‘;

重启master机的mysql服务：service mysqld restart

用show master status 命令看日志情况

mysql>show master status;

+-----------------+------------+-------------------+-----------------------+

| File                | Position     | Binlog_Do_DB   | Binlog_Ignore_DB |

+-----------------+------------+-------------------+-----------------------+

|    log.000003 |           98  | repl                 | mysql                    |

+-----------------+------------+-------------------+-----------------------+

1 row in set (0.00 sec)

2、修改slave机中mysql配置文件

同样在[mysqld]字段下添加如下内容

server-id=2

master-host=192.168.1.222

master-user=repl

master-password=123456

master-port=3306

master-connect-retry=60

replicate-do-db=repl //同步的数据库，不写本行 表示 同步所有数据库

然后重启slave机的mysql

在slave机中进入mysql

mysql>start slave;

mysql>show slave statusG;
如果Slave_IO_Running、Slave_SQL_Running状态为Yes则表明设置成功。

四、出现的问题

问题1 当我在执行start slave这条命令时，系统提示

ERROR 1200 (HY000): The server is not configured as slave; fix in config file or with CHANGE MASTER TO，

执行show slave status;又提示Empty set (0.00 sec)，想不通问题在哪里

或问题2 Slave_SQL_Running: No

后来发现，原来slave已经默认开启，要先关闭再开启

执行 slave stop;

再执行

change master to master_host=‘192.168.1.222‘,master_user=‘repl‘,master_password=‘123456‘, master_log_file=‘log.000003‘ ,master_log_pos=98;

然后执行 slave start;

这时 再执行show slave statusG

显示如下：

*************************** 1. row ***************************

             Slave_IO_State: Waiting for master to send event

                Master_Host: 192.168.1.222

                Master_User: repl

                Master_Port: 3306

              Connect_Retry: 60

            Master_Log_File: log.000003

        Read_Master_Log_Pos: 98

            Relay_Log_File: mysqld-relay-bin.000002

              Relay_Log_Pos: 229

      Relay_Master_Log_File: log.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: 98

            Relay_Log_Space: 229

            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

1 row in set (0.00 sec)

显示红色那两行，说明配置成功。

五、测试主从服务器是否能同步

在主服务器上面新建一个表，必须在repl数据下

mysql> use repl

Database changed

mysql> create table test(id int,name char(10));

Query OK, 0 rows affected (0.00 sec)

mysql> insert into test values(1,‘zaq‘);

Query OK, 1 row affected (0.00 sec)

mysql> insert into test values(1,‘xsw‘);

Query OK, 1 row affected (0.00 sec)

mysql> select * from test;

+------+------+

| id    | name |

+-------+------+

|    1    | zaq   |

|    1    | xsw |

+-------+------+

2 rows in set (0.00 sec)

在从服务器查看是否同步过来

mysql> use repl;

Database changed

mysql> select * from test;

+------+------+

| id    | name |

+------+------+

|     1 | zaq   |

|     1 | xsw |

+------+------+

2 rows in set (0.00 sec)

centos下MySQL主从同步配置