MySQL主从数据库配置

使用工具

MySQL数据版本：5.6.36-log、
两台云服务器（Linux系统）

首先，需要在Linux系统下安装MySQL,具体步骤可以参考这里，并且确保两台主机可以相互访问，可以直接ping一下。

配置Master

• 在Linux环境下，MySQL的配置文件在/ect/my.cnf，直接打开并编辑该文件：vim /etc/my.cnf
• 在[mysqld]下输入配置

  log-bin=mysql-bin
  server-id=2
  binlog-ignore-db=information_schema
  binlog-ignore-db=mysql
  binlog-do-db=rwtest

这里的server-id用于标识唯一的数据库，这里设置为2在设从库需要设置为其他值。

binlog-ignore-db：表示同步的时候ignore的数据库
binlog-do-db：指定需要同步的数据库

• 重启MySQL：service mysqld restart

• 登录MySQL并对访问用户进行授权：Slave机器需要File权限和REPLICATION SLAVE权限，当然也可以授予全部权限。

  grant file on *.* to 'root'@'%' identified by 'your password';
  
  grant replication slave on *.* to 'root'@'%' identified by 'your password';
  
  flush privileges;
  -------------------------------------------
  grant all privileges on *.* to 'root'@'%' identified by 'your password';
  
  flush privileges;

• 完成后，可以查看下Master的状态：show master status

  mysql> show master status;
  +------------------+----------+--------------+----------------------------------+-------------------+
  | File             | Position | Binlog_Do_DB | Binlog_Ignore_DB                 | Executed_Gtid_Set |
  +------------------+----------+--------------+----------------------------------+-------------------+
  | mysql-bin.000001 |     2272 | rwtest       | information_schema,mysql |                   |
  +------------------+----------+--------------+----------------------------------+-------------------+
  1 row in set (0.03 sec)

这里的File和Position在Slave中都要用到，Binlog_Do_DB指需要同步的数据库,Binlog_Ignore_DB指不需要同步的数据库，就是刚才配置的值。

配置Slave

• 同样在[mysqld]下对配置文件进行编写

  log-bin=mysql-bin
  server-id=3
  binlog-ignore-db=information_schema
  binlog-ignore-db=mysql
  replicate-do-db=rwtest
  replicate-ignore-db=mysql
  log-slave-updates
  slave-skip-errors=all
  slave-net-timeout=60

• 配置完毕后同样重启一下MySQL，并进入设置其对应的Master

  mysql> stop slave;  #关闭Slave
  mysql> change master to master_host='Master主机IP',master_user='刚才授权的用户',master_password='your password',master_log_file='mysql-bin.000001', master_log_pos=2272;
  
  mysql> start slave;  #开启Slave

master_log_file和master_log_pos都是Master的状态值。必须对应。

• 登录slave的数据库，查看slave的状态：show slave status \G

  Slave_IO_State: Waiting for master to send event
                    Master_Host: 你的Master主机IP
                    Master_User: root
                    Master_Port: 3306
                  Connect_Retry: 60
                Master_Log_File: mysql-bin.000001
            Read_Master_Log_Pos: 2272
                 Relay_Log_File: izwz9fcvpu481xh55cegx0z-relay-bin.000002
                  Relay_Log_Pos: 1339
          Relay_Master_Log_File: mysql-bin.000001
               Slave_IO_Running: Yes
              Slave_SQL_Running: Yes
                Replicate_Do_DB: rwtest
            Replicate_Ignore_DB: mysql
             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: 2272
                Relay_Log_Space: 1530
                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
                    Master_UUID: de20814f-2fb8-11e7-8f61-5254002b91a1
               Master_Info_File: /var/lib/mysql/master.info
                      SQL_Delay: 0
            SQL_Remaining_Delay: NULL
        Slave_SQL_Running_State: Slave has read all relay log; waiting for the slave I/O thread to update it
             Master_Retry_Count: 86400
                    Master_Bind:
        Last_IO_Error_Timestamp:
       Last_SQL_Error_Timestamp:
                 Master_SSL_Crl:
             Master_SSL_Crlpath:
             Retrieved_Gtid_Set:
              Executed_Gtid_Set:
                  Auto_Position: 0
  1 row in set (0.03 sec)

如果状态中含有没有报Error，则表示配置成功了。

接下来你通过可视化工具连接两个数据库，在主库中进行增删改操作，从库中也会有相应的操作，而在从库中进行此类操作对主库无效。