2018-4-2 15周1次課 MySQL主從配置
阿新 • • 發佈：2018-04-02
MySQL主從配置17.1 MySQL主從介紹
·MySQL主從又叫做Replication、AB復制。簡單講就是A和B兩臺機器做主從後，在A上寫數據，另外一臺B也會跟著寫數據，兩者數據實時同步的
·MySQL主從是基於binlog的，主上須開啟binlog才能進行主從。
·主從過程大致有3個步驟
1）主將更改操作記錄到binlog裏
2）從將主的binlog事件(sql語句)同步到從本機上並記錄在relaylog裏
3）從根據relaylog裏面的sql語句按順序執行
·主上有一個log dump線程，用來和從的I/O線程傳遞binlog
·從上有兩個線程，其中I/O線程用來同步主的binlog並生成relaylog，另外一個SQL線程用來把relaylog裏面的sql語句落地
備份庫
讀庫，減輕主庫的壓力
17.2 準備工作
安裝mysql
簡單步驟：
·wget 免編譯安裝包
·tar 解壓壓縮包
·mv 解壓出的目錄到/usr/local/mysql下 確保/usr/local/mysql空
·./scripts/mysql_install_db --user=mysql --datadir=/data/mysql 初始化並定義用戶和datadir（提前創建）
·編輯 /etc/my.cnf，定義datadir和socket位置
·cp support-files/mysql.server /etc/init.d/mysqld 復制啟動腳本到/etc/init.d下名稱為mysqld
·在mysqld中定義basedir，datadir
·啟動程序/etc/init.d/mysqld start
·chkconfig mysqld on 可以添加到開機啟動
確保進行主從的機器中，mysqld服務均已啟運行
安裝過程參考：http://blog.51cto.com/11530642/2073264
17.3 配置主
修改my.cnf，增加server-id=128（可以根據ip來定）和log_bin=alex（logbin的前綴）
[root@localhost mysql]# /etc/init.d/mysqld restart ##重啟mysqld Shutting down MySQL.. SUCCESS! Starting MySQL.. SUCCESS!
把mysql庫備份並恢復成aming庫，作為測試數據
[root@localhost mysql]# mysqldump -uroot -p123456 mysql > /tmp/mysql.sql ##備份數據庫 Warning: Using a password on the command line interface can be insecure. [root@localhost mysql]# mysql -uroot -p123456 -e'create database a4l' ##創建新庫 Warning: Using a password on the command line interface can be insecure. [root@localhost mysql]# mysql -uroot -p123456 a4l < /tmp/mysql.sql ##導入數據庫 Warning: Using a password on the command line interface can be insecure. [root@localhost mysql]# ll 總用量 177292 drwx------ 2 mysql mysql 4096 3月 31 20:51 a4l -rw-rw---- 1 mysql mysql 663420 3月 31 20:51 alex.000001 -rw-rw---- 1 mysql mysql 14 3月 31 20:34 alex.index -rw-rw---- 1 mysql mysql 56 3月 12 21:59 auto.cnf -rw-rw---- 1 mysql mysql 79691776 3月 31 20:51 ibdata1 -rw-rw---- 1 mysql mysql 50331648 3月 31 20:51 ib_logfile0 -rw-rw---- 1 mysql mysql 50331648 3月 12 21:47 ib_logfile1 -rw-rw---- 1 mysql mysql 111979 3月 31 20:34 localhost.localdomain.err -rw-rw---- 1 mysql mysql 5 3月 31 20:34 localhost.localdomain.pid drwx------ 2 mysql mysql 4096 3月 18 22:52 mysql drwx------ 2 mysql mysql 4096 3月 18 22:52 mysql2 drwx------ 2 mysql mysql 4096 3月 12 21:47 performance_schema drwx------ 2 mysql mysql 6 3月 12 21:47 test drwx------ 2 mysql mysql 324 3月 30 22:48 zrlog
創建用作主從同步的用戶：
[root@localhost mysql]# mysql -uroot -p123456 Warning: Using a password on the command line interface can be insecure. Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 5 Server version: 5.6.36-log MySQL Community Server (GPL) Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. mysql> grant replication slave on *.* to 'repl'@192.168.65.129 identified by '123456'; Query OK, 0 rows affected (0.00 sec) ## 創建用作同步數據的用戶 mysql> flush tables with read lock; ##鎖表，防止數據變動 Query OK, 0 rows affected (0.01 sec) mysql> show master status; +-------------+----------+--------------+------------------+-------------------+ | File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set | +-------------+----------+--------------+------------------+-------------------+ | alex.000001 | 663631 | | | | +-------------+----------+--------------+------------------+-------------------+ 1 row in set (0.00 sec)
備份需要同步的數據庫：
[root@localhost mysql]# mysqldump -uroot -p123456 a4l > /tmp/a4l.sql Warning: Using a password on the command line interface can be insecure. [root@localhost mysql]# mysqldump -uroot -p123456 mysql2 > /tmp/my2.sql Warning: Using a password on the command line interface can be insecure. [root@localhost mysql]# mysqldump -uroot -p123456 zrlog > /tmp/zrlog.sql Warning: Using a password on the command line interface can be insecure.
（mysql中有許多用戶名和密碼，沒辦法把權限全部復制，所以不需要同步）
17.4 配置從
安裝mysql
[root@localhost ~]# vim /etc/my.cnf
（從不需要bin_log,只有主才需要）
[root@localhost ~]# /etc/init.d/mysqld restart ##重啟mysqld Shutting down MySQL.. SUCCESS! Starting MySQL.. SUCCESS! [root@localhost ~]# ls /data/mysql/ auto.cnf ib_logfile0 localhost.localdomain.err mysql performance_schema ibdata1 ib_logfile1 localhost.localdomain.pid mysql2 test [root@localhost ~]# mysql -uroot -p123456 Warning: Using a password on the command line interface can be insecure. Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 2 Server version: 5.6.36 MySQL Community Server (GPL) Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. mysql> create database a4l; ##創建數據庫 Query OK, 1 row affected (0.00 sec) mysql> create database mysql2; Query OK, 1 row affected (0.00 sec) mysql> create database zrlog; Query OK, 1 row affected (0.00 sec) mysql> quit Bye ##導入數據 [root@localhost ~]# mysql -uroot -p123456 a4l < /tmp/a4l.sql Warning: Using a password on the command line interface can be insecure. [root@localhost ~]# mysql -uroot -p123456 mysql2 < /tmp/my2.sql Warning: Using a password on the command line interface can be insecure. [root@localhost ~]# mysql -uroot -p123456 zrlog < /tmp/zrlog.sql Warning: Using a password on the command line interface can be insecure.
傳輸數據：
[root@localhost ~]# scp 192.168.65.128:/tmp/*.sql /tmp/ The authenticity of host '192.168.65.128 (192.168.65.128)' can't be established. ECDSA key fingerprint is SHA256:PXl0tJsOm3464x52jTxX7L+ToKm1Hb6AUMq6lh4ASX0. ECDSA key fingerprint is MD5:2e:9a:f9:25:b3:80:43:05:a4:3d:3c:9b:48:6e:a0:0e. Are you sure you want to continue connecting (yes/no)? yes Warning: Permanently added '192.168.65.128' (ECDSA) to the list of known hosts. [email protected]'s password: a4l.sql 100% 648KB 23.2MB/s 00:00 my2.sql 100% 642KB 27.3MB/s 00:00 zrlog.sql 100% 10KB 3.1MB/s 00:00
[root@localhost ~]# mysql -uroot -p123456 Warning: Using a password on the command line interface can be insecure. Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 3 Server version: 5.6.36 MySQL Community Server (GPL) Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. mysql> stop slave; Query OK, 0 rows affected (0.00 sec) mysql> change master to master_host='192.168.65.128', master_user='repl', master_password='123456', master_log_file='alex.000001', master_log_pos=663631; Query OK, 0 rows affected, 2 warnings (0.01 sec) mysql> start slave; Query OK, 0 rows affected (0.01 sec) mysql> show slave status\G *************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 192.168.65.128 Master_User: repl Master_Port: 3306 Connect_Retry: 60 Master_Log_File: alex.000002 Read_Master_Log_Pos: 120 Relay_Log_File: localhost-relay-bin.000003 Relay_Log_Pos: 278 Relay_Master_Log_File: alex.000002 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: 120 Relay_Log_Space: 613 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: 128 Master_UUID: bc3bf10d-34ed-11e8-b6a9-000c297e8b1b Master_Info_File: /data/mysql/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: 0 1 row in set (0.00 sec)
status中兩個yes才是成功：
回到主服務器上，unlock tables
[root@localhost mysql]# mysql -uroot -p123456 Warning: Using a password on the command line interface can be insecure. Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 2 Server version: 5.6.36-log MySQL Community Server (GPL) Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. mysql> unlock tables; Query OK, 0 rows affected (0.00 sec)
錯誤匯總：
1，Slave_IO_Running: No
查看錯誤問題：
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.
查看主從服務器兩臺機器/data/mysql/auto.cnf的UUID是否一樣，如果一樣，刪除其中一個，並重啟該服務器，再次進行從服務器mysql的change master操作就能成功了。
17.5 測試主從同步
在my.cnf中定義：可以在主上，也可以在從上
主服務器上
binlog-do-db= //僅同步指定的庫，多個可以用 , 去分割
binlog-ignore-db= //忽略指定庫
從服務器上
replicate_do_db=
replicate_ignore_db=
replicate_do_table=
replicate_ignore_table=
replicate_wild_do_table= //如alex.%, 支持通配符%
replicate_wild_ignore_table=
（最長用是最後兩條）
從上刪除comment表中的信息，主上也沒了
主上刪除了comment表，從上comment表也不存在了
主上 mysql -uroot aming
select count(*) from db;
truncate table db;
到從上 mysql -uroot aming
select count(*) from db;
主上繼續drop table db;
從上查看db表
2018-4-2 15周1次課 MySQL主從配置