mysql数据库主从同步（交互式）

Posted 2022-01-06 mynale

 

mysql数据库主从同步交互式配置步骤，本文以一台mysql数据库多实例3306和3307为例进行配置，3306为主库，3307为从库（多台单实例与一台多实例配置是一样的）

一.my.cnf文件配置

1.修改my.cnf配置文件，主数据库3306要打开log-bin，server-id不能一样

[[email protected] ~]# egrep"log-bin|server-id" /data/3306,3307/my.cnf

/data/3306/my.cnf:log-bin=/data/3306/mysql-bin

/data/3306/my.cnf:server-id=1

/data/3307/my.cnf:#log-bin=/data/3307/mysql-bin

/data/3307/my.cnf:server-id=3

2.重启数据库3306和3307

[[email protected] ~]#/data/3306/mysql stop

[[email protected] ~]#/data/3306/mysql start

[[email protected] ~]#/data/3307/mysql stop 

[[email protected] ~]#/data/3307/mysql start

3.进入主数据库3306，查询log_bin是否打开，server_id是多少

[[email protected] ~]# mysql -uroot-p123456 -S /data/3306/mysql.sock

mysql> show variables like"log_bin";

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

| Variable_name | Value |

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

| log_bin       | ON   |

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

1 row in set (0.01 sec)

 

mysql> show variables like"server_id";

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

| Variable_name | Value |

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

| server_id     | 1    |

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

1 row in set (0.00 sec)

4.创建一个专门用来同步数据库的用户

mysql> grant replicationslave on *.* to [email protected]‘10.0.0.%‘ identified by ‘123456‘;

###*.*代表所有库和所有表

mysql> flush privileges;

mysql> select user,hostmysql.user;

mysql> show grants [email protected]‘10.0.0.%‘;

 

二.主库3306备份

mysql> flush table with readlock;          //锁表，这时为只读，不能写，此时mysql窗口不能退出，退出则锁表会失败，超出默认的锁表时间会自动解锁

mysql> show variables like‘timeout%‘;       //查看默认的锁表时间

mysql> show master status;             //查看binlog位置

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

| File               | Position | Binlog_Do_DB | Binlog_Ignore_DB       |

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

| mysql-bin.000004   |     328|              |                   |

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

1 row in set (0.00 sec)

[[email protected] ~]# mysqldump-uroot -p123456 -S /data/3306/mysql.sock -A -B|gzip >/opt/bak_$(date+%F).sql.gz     //从新打开一个CRT窗口，进行备份

[[email protected] ~]# ls /opt

bak_2017-06-28.sql.gz

mysql> show master status;     //备份数据后，再次查看binlog位置，确认这期间没有新数据写入

mysql> unlock tables;                       //解锁

 

 

 

三.把主库3306备份出来的数据还原到从库3307

1.登陆3307，确认logbin是关闭状态，server id与3306不冲突

[[email protected] ~]# mysql -uroot-p123456 -S /data/3307/mysql.sock

mysql> show variables like"log_bin";    

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

| Variable_name | Value |

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

| log_bin       | OFF |

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

1 row in set (0.01 sec)

 

mysql> show variables like"server_id";

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

| Variable_name | Value |

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

| server_id     | 3    |

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

1 row in set (0.00 sec)

2.将3306备份的数据还原到3307上

[[email protected] ~]# cd /opt

[[email protected] opt]# ls

bak_2017-06-28.sql.gz 

[[email protected] opt]# gzip -dbak_2017-06-28.sql.gz

[[email protected] opt]# ls

bak_2017-06-28.sql 

[[email protected] opt]# mysql -uroot-p123456 -S /data/3307/mysql.sock <bak_2017-06-28.sql

3.登陆3307，执行以下命令，连接主库3306

[[email protected] opt]# mysql -uroot-p123456 -S /data/3307/mysql.sock

mysql> CHANGE MASTER TO 

    -> MASTER_HOST=‘10.0.0.20‘,

    -> MASTER_PORT=3306,

    -> MASTER_USER=‘rep‘,

    -> MASTER_PASSWORD=‘123456‘,

    -> MASTER_LOG_FILE=‘mysql-bin.000004‘,

-> MASTER_LOG_POS=328;

mysql> start slave;               //从库3307开启主从复制开关

mysql> show slave status\\G       //检查同步状态

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

               Slave_IO_State: Waiting formaster to send event

                  Master_Host: 10.0.0.20

                  Master_User: rep

                  Master_Port: 3306

                Connect_Retry: 60

              Master_Log_File: mysql-bin.000004

          Read_Master_Log_Pos: 328

               Relay_Log_File: relay-bin.000002

                Relay_Log_Pos: 253

        Relay_Master_Log_File: mysql-bin.000004

             Slave_IO_Running:Yes    //确认这两条是yes状态

            Slave_SQL_Running: Yes

              Replicate_Do_DB:

          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: 328

              Relay_Log_Space: 403

              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     //复制过程中从库比主库延迟的秒数

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)

或者这样检查同步状态

[[email protected] ~]# mysql -uroot-p123456 -S /data/3307/mysql.sock  -e"show slave status\\G"|egrep -i "running|_behind"     //-e的作用是不需要登陆mysql交互敲入命令

             Slave_IO_Running: Yes

            Slave_SQL_Running: Yes

        Seconds_Behind_Master: 0

查看线程状态

[[email protected] ~]# mysql -uroot -p123456 -S/data/3307/mysql.sock -e "show processlist\\G"

[[email protected] ~]# mysql -uroot -p123456 -S/data/3306/mysql.sock -e "show processl

 

四.测试

在主库3306上创建数据库，然后再登陆3307查看是否正常同步，经测试已正常同步^_^