規劃
master 192.168.56.2
slave 192.168.56.5
1、在主庫上,設定一個複製使用的賬戶rep1,並授予REPLICATION SLAVE許可權。
mysql> grant replication slave on *.* to 'rep1'@'192.168.56.2' identified by '123456';Query OK, 0 rows affected (0.01 sec)
2、修改主要資料庫伺服器的設定檔my.cnf,開啟BINLOG,並設定server-id的值。這兩個參數的修改需要重新啟動資料庫服務才可以生效。
vi /etc/my.cnf
[mysqld]
log-bin=/home/mysql/log/mysql-bin.log
server-id=1
[root@rhel6 ~]# service mysql restartShutting down MySQL.. [ OK ]Starting MySQL. [ OK ]
3、在主庫上,設定讀鎖定有效,這個操作是為了確保沒有資料庫操作,以便獲得一個一致性的快照。
mysql> flush tables with read lock;Query OK, 0 rows affected (0.02 sec)
4、得到主庫上當前的二進位日誌名和位移量值。這個操作的目的是為了從資料庫啟動以後,從這個點開始進行資料的恢複。
mysql> show master status;+-----------------+----------+--------------+------------------+-------------------+| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |+-----------------+----------+--------------+------------------+-------------------+| mysqlbin.000021 | 120 | | | |+-----------------+----------+--------------+------------------+-------------------+1 row in set (0.03 sec)
5、現在主要資料庫伺服器已經停止了更新操作,需要產生主要資料庫的備份,備份的方式有很多種,可以直接在作業系統下複製全部的資料檔案到從資料庫伺服器上,也可以通過mysqldump匯出資料或者使用ibbackup工具進行資料庫的備份。如果主要資料庫的服務可以停止,那麼直接複製資料檔案應該是最快的產生快照的方法:
[root@rhel6 lib]# tar -zcvf mysql.tar.gz mysqlmysql/tar: mysql/mysql.sock: socket ignoredmysql/mysqlbin.000019mysql/test1/mysql/test1/db.optmysql/test1/pack.MYDmysql/test1/myisam2.frmmysql/test1/emp.ibdmysql/test1/mer_myisam.MRGmysql/test1/emp.frmmysql/test1/pri_t.TRG....傳到從資料庫[root@rhel6 lib]# scp mysql.tar.gz root@192.168.56.5:/rootroot@192.168.56.5's password: mysql.tar.gz 100% 1402KB 1.4MB/s 00:00
6、主要資料庫備份完畢後可恢複寫操作,剩下的只需要在從庫上執行
mysql> unlock tables;Query OK, 0 rows affected (0.02 sec)
7、將主要資料庫的一致性備份恢複到從資料庫上。如果是使用.tar.gz打包的檔案包,只需要解開到相應的目錄即可。
tar -zxvf mysql.tar.gz
8、修改從資料庫的設定檔my.cnf,增加server-id參數。注意server-id的值必須是唯一的,不能和主要資料庫的配置相同,如果有多個從資料庫伺服器,每個從資料庫伺服器必須有自己唯一的server-id值。
vi my.cnf
[mysqld]
server-id=2
9、在從庫上,使用--skip-slave-start選項啟動資料庫,這樣不會立即啟動從資料庫服務上的複製進程,方便我們對從資料庫的服務進行進一步的配置(可選)
mysqld_safe --skip-slave-start &
或者修改my.cnf,添加skip-slave-start參數,service mysql start
10、對從資料庫伺服器做相應設定,指定複製使用的使用者,主要資料庫伺服器的IP、連接埠以及開始執行複製的記錄檔和位置等
mysql> change master to -> master_host='192.168.56.2', -> master_user='rep1', -> master_port=3306, -> master_password='123456', -> master_log_file='mysqlbin.000021', -> master_log_pos=120;Query OK, 0 rows affected, 2 warnings (0.08 sec)
11、在從庫上,啟動slave線程
mysql> start slave;Query OK, 0 rows affected (0.17 sec)
12、從庫上查看進程
mysql> show processlist \G;*************************** 1. row *************************** Id: 1 User: root Host: localhost db: zxCommand: Query Time: 0 State: init Info: show processlist*************************** 2. row *************************** Id: 4 User: system user Host: db: NULLCommand: Connect Time: 1484 State: Waiting for master to send event Info: NULL*************************** 3. row *************************** Id: 5 User: system user Host: db: NULLCommand: Connect Time: 739 State: Slave has read all relay log; waiting for the slave I/O thread to update it Info: NULL3 rows in set (0.00 sec)mysql> show slave status \G*************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 192.168.56.2 Master_User: rep1 Master_Port: 3306 Connect_Retry: 60 Master_Log_File: mysqlbin.000021 Read_Master_Log_Pos: 652 Relay_Log_File: rhel6-relay-bin.000002 Relay_Log_Pos: 814 Relay_Master_Log_File: mysqlbin.000021 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: 652 Relay_Log_Space: 987 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: 0Master_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: 3743271b-aa6d-11e6-aa2e-080027e5f5dd Master_Info_File: /mysqldata/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: 01 row in set (0.00 sec)
Slave_IO_Running和Slave_SQL_Running全部為YES才算搭建成功。如果出錯查看報錯原因。我搭建時遇到的兩個錯誤:
(1)Last_IO_Error: Fatal error: The slave I/O thread stops because master and slave have equal MySQL server UUIDs; these UUIDs must be different for replication to work.
原因:搭建時把主庫整個目錄複寫過來的,主庫和從庫的UUID一致了,修改從庫的UUID即可。
方法:修改$datadir/auto.cnf,按照16進位格式隨便改一下,重啟mysql即可。
(2)Last_IO_Error: Got fatal error 1236 from master when reading data from binary log: 'Could not find first log file name in binary log index file'
原因:配置change master to時把master_log_file配置錯誤
方法:change master to master_log_file='mysqlbin.000021';start slave;即可。
13、測試複製的正確性
主庫mysql> create database zx;Query OK, 1 row affected (0.05 sec)mysql> use zx;Database changedmysql> create table t(id int);Query OK, 0 rows affected (0.09 sec)mysql> insert into t values(1),(2),(3);Query OK, 3 rows affected (0.01 sec)Records: 3 Duplicates: 0 Warnings: 0從庫mysql> show databases;+--------------------+| Database |+--------------------+| information_schema || data || mysql || performance_schema || test || test1 || zx |+--------------------+7 rows in set (0.00 sec)mysql> use zxReading table information for completion of table and column namesYou can turn off this feature to get a quicker startup with -ADatabase changedmysql> select * from t;+------+| id |+------+| 1 || 2 || 3 |+------+3 rows in set (0.00 sec)