MySQL主从复制操作
前期准备：
两台安装MySQL的服务器，或者在一台服务器上部署两个MySQL实例。为了避免出现不必要的错误，MySQL版本最好保持一致。
+----------------+----------+-------------+-----------+----------+----------+
|服务器地址 |主机名 |数据库版本 |数据库端口 |server_id |角色 |
+----------------+----------+-------------+-----------+----------+----------+
|192.168.175.248 |Mysql-248 |Mysql-5.6.30 |3306 |1 |主库Master|
+----------------+----------+-------------+-----------+----------+----------+
|192.168.175.249 |Mysql-249 |Mysql-5.6.30 |3306 |2 |从库Slave |
+----------------+----------+-------------+-----------+----------+----------+
一、 主库配置：
1. 开启二进制日志，配置server_id（需要重启生效）。
[root@Mysql-248 mysql-5.6.30]# grep -A3 'mysqld' my.cnf
[mysqld]
port = 3306
server_id = 1
log-bin=mysql-bin
检验二进制日志状态，ON为打开：
mysql> show variables like 'log_bin' ;
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| log_bin | ON |
+---------------+-------+
1 row in set (0.00 sec)
2. 在主库建立Mysql复制用户。
mysql> grant replication slave on *.* to 'repl_user'@'192.168.175.%' identified by '123456';
Query OK, 0 rows affected (0.00 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
3. 在主库上锁表备份，然后解锁。
锁表，锁表后当前窗口暂时不能关闭：
mysql> flush tables with read lock;
Query OK, 0 rows affected (0.01 sec)
查看master状态信息：
mysql> show master status;
+------------------+----------+-------------+------------------+-------------------+
| File | Position | Binlog_Do_DB| Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+-------------+------------------+-------------------+
| mysql-bin.000001 | 414 | | | |
+------------------+----------+-------------+------------------+-------------------+
1 row in set (0.00 sec)
新建ssh窗口，备份数据库：
[root@Mysql-248 ~]# mysqldump -uroot -p'qwe123``' -A > /tmp/master248.sql
备份完成后，在原先窗口中解锁：
mysql> unlock tables;
Query OK, 0 rows affected (0.00 sec)
二、从库配置：
1. 配置从库server_id与relay-log（需要重启生效）。
注意：server_id必须是唯一的，不能与其他mysql库相同。从库无需开启二进制日志。
[root@Mysql-249 mysql-5.6.30]# grep mysqld -A3 my.cnf
[mysqld]
port = 3306
server_id = 2
relay-log = mysql-relay-bin
2. 将主库的备份拷贝到本机，导入数据库。
拷贝备份：
[root@Mysql-249 mysql-5.6.30]# scp [email protected]:/tmp/master248.sql /tmp/
[email protected]'s password:
master248.sql
导入：
[root@Mysql-249 mysql-5.6.30]# mysql -uroot -p'qwe123``' < /tmp/master248.sql
Warning: Using a password on the command line interface can be insecure.
3. 指定master服务器信息，开启slave。
指定master信息：
mysql> change master to \
-> master_host='192.168.175.248',
-> master_user='repl_user',
-> master_password='123456',
-> master_log_file='mysql-bin.000001',
-> master_log_pos=414;
Query OK, 0 rows affected, 2 warnings (0.03 sec)
开启slave:
mysql> start slave;
Query OK, 0 rows affected (0.01 sec)
三、检验主从复制：
1. 在从库使用show slave status\G，查询主库信息以及IO进程、SQL进程工作状态。
mysql> show slave status\G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.175.248
Master_User: repl_user
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000001
Read_Master_Log_Pos: 414
Relay_Log_File: mysql-relay-bin.000002
Relay_Log_Pos: 283
Relay_Master_Log_File: mysql-bin.000001
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
......
1 row in set (0.00 sec)
查询结果显示Slave_IO_Running: Yes，Slave_SQL_Running: Yes，表示当前主从复制状态正常。
2. 在master新建数据库，在slave查询，测试主从复制效果。
Master建库建表。
mysql> create database cubix character set utf8;
Query OK, 1 row affected (0.00 sec)
mysql> use cubix
Database changed
mysql> create table T1 (id int);
Query OK, 0 rows affected (0.02 sec)
mysql> insert into T1 VALUES ('1');
Query OK, 1 row affected (0.00 sec)
mysql> insert into T1 VALUES ('2');
Query OK, 1 row affected (0.00 sec)
mysql> insert into T1 VALUES ('3');
Query OK, 1 row affected (0.01 sec)
Slave查询新建的库。
mysql> show databases;
+-------------------+
| Database |
+-------------------+
| information_schema|
| cubix |
| mysql |
| performance_schema|
+-------------------+
6 rows in set (0.00 sec)
mysql> use cubix
Database changed
mysql> show tables;
+----------------+
| Tables_in_cubix|
+----------------+
| T1 |
+----------------+
1 row in set (0.00 sec)
mysql> select * from T1;
+------+
| id |
+------+
| 1 |
| 2 |
| 3 |
+------+
3 rows in set (0.00 sec)
检查发现在主库上新增的数据，在从库上也有了，也可以证明主从同步正常。