mysql主從復制環境可以說是一切高可用的基礎。它的原理也比較簡單,下面我們先來了解下主從復制的原理:
雖然圖上一共有7步,可以簡化一下幫助記憶和理解:
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Master上進行改、寫操作;
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MySQL把修改數據寫進binlog;
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Slave發起IO thread,把master上新的binlog拉取到本地中繼日志中;
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重放中繼日志,讓在master上面的修改、新增操作在Slave本機上重新運行一遍;
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Slave按照正常的操作也會把操作寫進本地的binlog。
硬件環境
本人有阿里云、騰訊云各一臺屌絲機,因此用來試驗,為保護隱私,把ip已經替換了,但不影響操作。
主機 | ip | 端口 | 版本 | 主從 |
---|---|---|---|---|
阿里云 | 192.168.1.100 | 3306 | MySQL5.7.14 | Master |
騰訊云 | 192.168.1.200 | 3306 | MySQL5.7.18 | Slave |
Master上設置
開啟binlog設置server-id
在/etc/my.cnf中的mysqld選項下編輯,然后重啟
[mysqld] log-bin=mysql-bin server-id=1003306
/etc/init.d/mysql restart
創建復制專用賬號
mysql> CREATE USER 'repl'@'%.mydomain.com' IDENTIFIED BY 'slave; mysql> GRANT REPLICATION SLAVE ON *.* TO 'repl'@'192.168.1.200';
導出數據同步到騰訊云上面
使用mysqldump導出所有數據庫數據,另外備份文件中會記錄當前的binlog文件和position。
#防止DDL、寫操作 mysql>FLUSH TABLES WITH READ LOCK; shell>mysqldump -uroot -p --single-transaction --master-data=2 -A>back.sql
也通過以下方式可以查看:
root@localhost [mysql]>show master status; +------------------+----------+--------------+------------------+-------------------+ | File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set | +------------------+----------+--------------+------------------+-------------------+ | mysql-bin.000045 | 939 | | | | +------------------+----------+--------------+------------------+-------------------+ 1 row in set (0.00 sec)
解鎖表
mysql> UNLOCK TABLES;
遠程傳文件過去
如果數據文件偏大或者數據多,可以使用percona的xtrabackup進行備份壓縮,再傳過去。
rsync back.sql root@192.168.1.200:/root
Slave操作
開啟binlog設置server-id
在/etc/my.cnf中的mysqld選項下編輯
[mysqld] log-bin=mysql-bin server-id=2003306
重啟MySQL服務
導入數據
shell>mysqldump -uroot -p --databases t1 <back.sql
指向Master
這里的MASTER_LOG_FILE和MASTER_LOG_POS是剛才show master status的值,當然也可以使用more查看應該指定的位置。
CHANGE MASTER TO MASTER_HOST='192.168.1.200',MASTER_PORT=3306,MASTER_USER='repl',MASTER_PASSWORD='slave',MASTER_LOG_FILE='mysql-bin.000045',MASTER_LOG_POS=939;
這里的MASTER_LOG_FILE和MASTER_LOG_POS是剛才show master status的值,當然也可以使用more查看應該指定的位置。
shell>more back.sql -- MySQL dump 10.13 Distrib 5.7.14, for linux-glibc2.5 (x86_64) -- -- Host: localhost Database: -- ------------------------------------------------------ -- Server version 5.7.14-log /*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */; /*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */; /*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */; /*!40101 SET NAMES utf8 */; /*!40103 SET @OLD_TIME_ZONE=@@TIME_ZONE */; /*!40103 SET TIME_ZONE='+00:00' */; /*!40014 SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0 */; /*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */; /*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */; /*!40111 SET @OLD_SQL_NOTES=@@SQL_NOTES, SQL_NOTES=0 */; -- -- Position to start replication or point-in-time recovery from -- CHANGE MASTER TO MASTER_LOG_FILE='mysql-bin.000045', MASTER_LOG_POS=939;
啟動slave
mysql>start slave; mysql>show slave statusG *************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 192.168.1.200 Master_User: repl Master_Port: 3306 Connect_Retry: 60 Master_Log_File: mysql-bin.000045 Read_Master_Log_Pos: 939 Relay_Log_File: relay-bin.000001 Relay_Log_Pos: 4 Relay_Master_Log_File: mysql-bin.000045 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: 939 Relay_Log_Space: 154 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: 23306 Master_UUID: 9a13d860-b55b-11e6-bf33-00163e054164 Master_Info_File: /data/mysql/mysql3306/data/master.info SQL_Delay: 0 SQL_Remaining_Delay: NULL Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates 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: 3feb36dc-ef7e-11e6-a535-52540043f116:1-337886 Auto_Position: 0 Replicate_Rewrite_DB: Channel_Name: Master_TLS_Version: 1 row in set (0.00 sec)
這里看到Slave_IO_Running和Slave_SQL_Running雙YES一般就沒有問題了。
驗證
現在可以在主上面進行一些新建數據庫、新建數據表、插入輸出等方式來驗證是否主從生效。此步驟就大家自己隨意發揮吧!