centos7上mysql5.6版本主从复制

做主从复制实验：

第一步：主服务器上操作

1、修改主服务器master:

[root@localhost ~]# vim /etc/my.cnf
server_id = 1  //[必须]服务器唯一ID，默认是1
log-bin=mysql-bin //[必须]启用二进制日志

2、重启主数据库

[root@localhost ~]# systemctl restart mysqld

3、在主服务器上建立帐户并授权slave:

mysql> grant replication slave on *.* to 'zhangsan'@'%' identified by '123456';
Query OK, 0 rows affected (0.00 sec)

mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)

4、登录主服务器的mysql，查询master的状态

mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000001 |      401 |              |                  |                   |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)

注：执行完此步骤后不要再操作主服务器MYSQL，防止主服务器状态值变化

第二步：从服务器操作

1、修改从服务器slave:

[root@localhost ~]# vim /etc/my.cnf
 server_id = 2
log-bin=mysql-bin

2、重启从数据库

[root@localhost ~]# systemctl restart mysqld

3、配置从服务器Slave：

mysql> change master to master_host='192.168.35.131',master_user='zhangsan',master_password='123456', master_log_file='mysql-bin.000001',master_log_pos=401;
Query OK, 0 rows affected, 2 warnings (0.02 sec)

mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)

4、启动从服务器复制功能并检查从服务器复制功能状态

mysql> start slave;
Query OK, 0 rows affected (0.13 sec)

mysql> show slave status \G;
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.35.131  //主服务器地址
                  Master_User: zhangsan     //授权帐户名，尽量避免使用root
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000001
          Read_Master_Log_Pos: 401   //#同步读取二进制日志的位置，大于等于Exec_Master_Log_Pos
               Relay_Log_File: localhost-relay-bin.000002
                Relay_Log_Pos: 283
        Relay_Master_Log_File: mysql-bin.000001
             Slave_IO_Running: Yes    //此状态必须YES
            Slave_SQL_Running: Yes    //此状态必须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: 401
              Relay_Log_Space: 460
              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
                  Master_UUID: 31f8646b-484e-11e8-b503-000c298f5b19
             Master_Info_File: /data/mysqldb/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 (0.00 sec)

ERROR:
No query specified

注：Slave_IO及Slave_SQL进程必须正常运行，即YES状态，否则都是错误的状态(如：其中一个NO均属错误)。

第三步：检测主从配置

1、在主数据库中创建一个库data，查看从库中是否有

主库中：

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| test               |
+--------------------+
4 rows in set (0.00 sec)

mysql> create database data;
Query OK, 1 row affected (0.00 sec)

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| data               |
| mysql              |
| performance_schema |
| test               |
+--------------------+
5 rows in set (0.00 sec)

2、从库中查看：

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| data               |
| mysql              |
| performance_schema |
| test               |
+--------------------+
5 rows in set (0.00 sec)

能够看到从库中是有data库的，说明主从复制配置完成，但是要注意，从表里不能做更新，删除等操作，只能使用查询，所以要慎重。

总结：完成以上操作过程，主从服务器配置完成。