mysql 快速设置主从同步

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最新推荐文章于 2024-09-03 16:50:46 发布

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文章标签： mysql 主从同步

本文链接：https://blog.csdn.net/default7/article/details/87972636

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本文介绍了MySQL主从同步的快速设置步骤，包括开启bin-log、设置server-id、配置slave、授权及错误处理。在完成步骤后，通过监控主从状态确保同步成功。注意，主从同步中，slave需获得master的复制权限，且两者都需设置相应的访问配置。

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MySQL主从同步用在读写分离或数据备份，快速设置步骤如下：

设置步骤

1.先开启master slave的bin-log 并设置 server-id，然后重启mysql检查是否设置OK。
2.得到master的MASTER_LOG_FILE 和MASTER_LOG_POS，在master上运行以下语句：

mysql> show master status\G
*************************** 1. row ***************************
            File: mysql-bin.000085
        Position: 223251
    Binlog_Do_DB: 
Binlog_Ignore_DB: 
1 row in set (0.00 sec)

3.在master上加入slave用户slave1，并给予slave权限

create user slave1@'%' identified by 'slave1';
grant replication slave on *.* to slave1@'%';
flush privileges;

4.登陆slave，进行配置并且开启：

CHANGE MASTER TO 
MASTER_HOST='192.168.1.223',
MASTER_USER='slave1',
MASTER_PASSWORD='slave1',
MASTER_LOG_FILE='mysql-bin.000085',
MASTER_LOG_POS=223251;

start slave;

5.在master上看是否有主从同步：

mysql> show processlist;
+--------+------------+---------------------+------------------+-------------+------+-----------------------------------------------------------------------+------------------+
| Id     | User       | Host                | db               | Command     | Time | State                                                                 | Info             |
+--------+------------+---------------------+------------------+-------------+------+-----------------------------------------------------------------------+------------------+
| 190305 | root       | localhost           | master1          | Query       |    0 | NULL                                                                  | show processlist |
| 190324 | slave1     | 192.168.1.204:51903 | NULL             | Binlog Dump | 6704 | Master has sent all binlog to slave; waiting for binlog to be updated | NULL             |
| 190765 | root       | 127.0.0.1:55186     | rap_db           | Sleep       |   31 |                                                                       | NULL             |
| 190766 | root       | 127.0.0.1:55187     | rap_db           | Sleep       |   31 |                                                                       | NULL             |
| 190767 | root       | 127.0.0.1:55188     | rap_db           | Sleep       |   31 |                                                                       | NULL             |
| 190768 | root       | 127.0.0.1:55189     | rap_db           | Sleep       |   31 |                                                                       | NULL             |
| 190769 | root       | 127.0.0.1:55190     | rap_db           | Sleep       |   31 |                                                                       | NULL             |
+--------+------------+---------------------+------------------+-------------+------+-----------------------------------------------------------------------+------------------+
7 rows in set (0.00 sec)

此刻 slave的processlist

mysql> show processlist;
+----+-------------+-----------------+---------+---------+------+--------------------------------------------------------+------------------+
| Id | User        | Host            | db      | Command | Time | State                                         | Info             |
+----+-------------+-----------------+---------+---------+------+--------------------------------------------------------+------------------+
|  3 | root        | localhost:49256 | master1 | Query   |    0 | starting                                         | show processlist |
| 10 | system user |                 | NULL    | Connect | 6777 | Waiting for master to send event                       | NULL             |
| 13 | system user |                 | NULL    | Connect | 1525 | Slave has read all relay log; waiting for more updates | NULL             |
+----+-------------+-----------------+---------+---------+------+--------------------------------------------------------+------------------+
3 rows in set (0.00 sec)

主从同步创建成功，这个时候可以在master 的这个数据库里面创建表，然后观察 slave是否有对应变化。

注意事项

mysql主从同步是slave 主动去链接master，所以需要在master上设置一个给slave的访问权限。
而slave上必须设有对master的访问设置。

错误处理

错误1：无访问权限

Last_IO_Error: Master command COM_REGISTER_SLAVE failed: Access denied for user 'slave1'@'%' (using password: YES) (Errno: 1045)

原因：slave只需要 replication 权限。
解决办法：master上执行下面一句，然后slave上再start slave重启slave即可。

grant replication slave on *.* to slave1@'%';
flush privileges;

错误2：

Duplicate entry '3' for key 'PRIMARY'' on query. Default database: 'master1'. Query: 'insert into sphinx(type) values (22)'

测试在slave对应表里面新增一条master不存在的记录，在 slave上查看show slave status 会有报错

mysql> show slave status\G
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.1.223
                  Master_User: slave1
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000085
          Read_Master_Log_Pos: 224849
               Relay_Log_File: USER-20180409EL-relay-bin.000002
                Relay_Log_Pos: 1445
        Relay_Master_Log_File: mysql-bin.000085
             Slave_IO_Running: Yes
            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: 1062
                   Last_Error: Error 'Duplicate entry '3' for key 'PRIMARY'' on query. Default database: 'master1'. Query: 'insert into sphinx(type) values (22)'
                 Skip_Counter: 0
          Exec_Master_Log_Pos: 224392
              Relay_Log_Space: 2119
              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: 1062
               Last_SQL_Error: Error 'Duplicate entry '3' for key 'PRIMARY'' onquery. Default database: 'master1'. Query: 'insert into sphinx(type) values (22)'
  Replicate_Ignore_Server_Ids:
             Master_Server_Id: 1
                  Master_UUID:
             Master_Info_File: D:\mysql\Data\master.info
                    SQL_Delay: 0
          SQL_Remaining_Delay: NULL
      Slave_SQL_Running_State:
           Master_Retry_Count: 86400
                  Master_Bind:
      Last_IO_Error_Timestamp:
     Last_SQL_Error_Timestamp: 190227 12:48:41
               Master_SSL_Crl:
           Master_SSL_Crlpath:
           Retrieved_Gtid_Set:
            Executed_Gtid_Set:
                Auto_Position: 0
         Replicate_Rewrite_DB:
                 Channel_Name:
           Master_TLS_Version:
1 row in set (0.00 sec)

解决办法，删除slave中该条记录。

最后

slave上查看slave状态


mysql> show slave status\G
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.1.223
                  Master_User: slave1
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000085
          Read_Master_Log_Pos: 225050
               Relay_Log_File: USER-20180409EL-relay-bin.000002
                Relay_Log_Pos: 2103
        Relay_Master_Log_File: mysql-bin.000085
             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: 225050
              Relay_Log_Space: 2320
              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:
             Master_Info_File: D:\mysql\Data\master.info
                    SQL_Delay: 0
          SQL_Remaining_Delay: NULL
      Slave_SQL_Running_State: Slave has read all relay log; waiting for more up
dates
           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
         Replicate_Rewrite_DB:
                 Channel_Name:
           Master_TLS_Version:
1 row in set (0.00 sec)

mysql>

master上查看 master状态

mysql> show master status\G
*************************** 1. row ***************************
            File: mysql-bin.000085
        Position: 225050
    Binlog_Do_DB: 
Binlog_Ignore_DB: 
1 row in set (0.00 sec)

mysql>