mysql數據庫實現主從複製

時間 2019-11-09

原文原文鏈接

服務器準備

主服務器：192.168.93.103
從服務器：192.168.93.102node

主服務器操做

修改配置文件

[root@CentOS7 ~]#vim /etc/my.cnf

[mysqld]
server_id=103                               //指定一個服務id,若是不寫這裏默認爲1
log_bin=/data/mysql/bin/mysql-bin           //必須啓動二進制日誌
binlog_format=row                           //建議使用行row記錄日誌
innodb_file_per_table
datadir=/var/lib/mysql

建立主從複製用戶

MariaDB [(none)]> grant replication slave on *.* to repluser@'192.168.93.%'identified by 'centos';

查看主服務器的二進制日誌，記錄要複製的位置mysql

[root@node-103 ~]#mysql -e 'show master logs';
+------------------+-----------+
| Log_name         | File_size |
+------------------+-----------+
| mysql-bin.000002 |       288 |
| mysql-bin.000003 |       288 |
| mysql-bin.000004 |       442 |
| mysql-bin.000005 |       245 |
+------------------+-----------+

如何解決主從複製一臺已存在大量數據的mysql服務器？

問題描述：若是一臺mysql主服務器已經運行了一段時間，主服務器的數據量很是大，而主從複製時間會很長，對主服務器壓力過大sql

解決辦法：先在主服務器上建立徹底備份，還原到從服務器上後，再作主從複製數據庫

徹底備份數據庫vim

[root@CentOS7 ~]#mysqldump -A --single-transaction -F --master-data=1 > /data/backup/all.sql

查看記錄二進制日誌中要複製的位置信息centos

[root@CentOS7 ~]#vim /data/backup/all.sql 

CHANGE MASTER TO MASTER_LOG_FILE='mysql-bin.000018', MASTER_LOG_POS=245;

在從服務器須要作的操做：
修改配置文件
將主服務器徹底備份的數據庫文件all.sql拷貝至從服務器服務器

[root@CentOS7 ~]#scp 192.168.93.102:/data/backup/all.sql  /data/backup

修改/data/backup/all.sql文件裏徹底備份位置語句：
CHANGE MASTER TO MASTER_LOG_FILE='mysql-bin.000018',MASTER_LOG_POS=245;
修改成：ide

vim /data/backup/all.sql

CHANGE MASTER TO
MASTER_HOST='192.168.93.103',                  
MASTER_USER='repluser',  
MASTER_PASSWORD='centos',  
MASTER_PORT=3306,
MASTER_LOG_FILE='mysql-bin.000018',
MASTER_LOG_POS=245;

而後導入all.sql文件線程

[root@CentOS7 ~]# mysql < all.sql

啓動主從同步線程日誌

MariaDB [(none)]> start slave;

從服務器操做

修改配置文件

[root@CentOS7 ~]# vim /etc/my.cnf

[mysqld]
server_id=102    //指定從服務器的服務id，不能不寫，默認爲1，此id不能與其餘服務器衝突
read_only=ON        //設置數據庫只讀

使用有複製權限的用戶帳號鏈接至主服務器，配置同步信息

MariaDB [(none)]> CHANGE MASTER TO 
MASTER_HOST='192.168.93.103',  //遠程主服務器IP
MASTER_USER='repluser',             //主從複製的用戶名
MASTER_PASSWORD=’centos’,         //密碼
MASTER_PORT=3306,                 //端口號
MASTER_LOG_FILE='mysql-bin.000017',  //要複製的主服務器的二進制文件名 
MASTER_LOG_POS=245;           //要開始複製的位置

啓動複製線程

MariaDB [(none)]> start  slave;
Query OK, 0 rows affected (0.00 sec)

顯示線程列表

MariaDB [(none)]> show processlist;
+----+-------------+-----------+------+---------+--------+-----------------------------------------------------------------------------+------------------+----------+
| Id | User        | Host      | db   | Command | Time   | State                                                                       | Info             | Progress |
+----+-------------+-----------+------+---------+--------+-----------------------------------------------------------------------------+------------------+----------+
|  3 | root        | localhost | NULL | Query   |      0 | NULL                                                                        | show processlist |    0.000 |
|  6 | system user |           | NULL | Connect |    264 | Waiting for master to send event                                            | NULL             |    0.000 |
|  7 | system user |           | NULL | Connect | -27302 | Slave has read all relay log; waiting for the slave I/O thread to update it | NULL             |    0.000 |
+----+-------------+-----------+------+---------+--------+-----------------------------------------------------------------------------+------------------+----------+
3 rows in set (0.00 sec)

顯示主服務器的狀態信息

MariaDB [(none)]> show slave status\G;
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.93.103
                  Master_User: repluser
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000017
          Read_Master_Log_Pos: 399
               Relay_Log_File: mariadb-relay-bin.000002
                Relay_Log_Pos: 683
        Relay_Master_Log_File: mysql-bin.000017
             Slave_IO_Running: Yes   //主從複製的線程IO
            Slave_SQL_Running: Yes   //主從複製的線程SQL
              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: 399
              Relay_Log_Space: 979
              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         //主從複製的時間差
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: 103
1 row in set (0.00 sec)

ERROR: No query specified