mysql 单台机器多实例

MySQL多实例

1.实例

1.单实例：
	1个进程 + 多个线程 + 单个预分配的内存空间

2.多实例：
	多个进程 + 多个线程 + 多个预分配的内存空间

3.MySQL多实例：
	1）多个端口
	2）多个socket文件
	3）多个server_id
	4）多个日志文件
	5）多个配置文件
	6）多个数据目录

2.创建多实例存放目录

[root@db02 /service]# mkdir /service/{3307,3308,3309}

3.配置多个配置文件

[root@db02 /service]# vim /service/3307/my.cnf
[mysqld]
basedir=/service/mysql
datadir=/service/3307/data
port=3307
socket=/service/3307/data/mysql.sock
server_id=7
log-error=/service/3307/data/mysql.err

[root@db02 /service]# vim /service/3308/my.cnf
[mysqld]
basedir=/service/mysql
datadir=/service/3308/data
port=3308
socket=/service/3308/data/mysql.sock
server_id=8
log-error=/service/3308/data/mysql.err

[root@db02 /service]# vim /service/3309/my.cnf
[mysqld]
basedir=/service/mysql
datadir=/service/3309/data
port=3309
socket=/service/3309/data/mysql.sock
server_id=9
log-error=/service/3309/data/mysql.err

4.初始化多实例数据目录

[root@db02 /service]# cd mysql/scripts/
[root@db02 /service/mysql/scripts]# ./mysql_install_db --defaults-file=/service/3307/my.cnf --user=mysql --basedir=/service/mysql --datadir=/service/3307/data
[root@db02 /service/mysql/scripts]# ./mysql_install_db --defaults-file=/service/3308/my.cnf --user=mysql --basedir=/service/mysql --datadir=/service/3308/data
[root@db02 /service/mysql/scripts]# ./mysql_install_db --defaults-file=/service/3309/my.cnf --user=mysql --basedir=/service/mysql --datadir=/service/3309/data

[root@db02 /service]# tree -L 3 ./
./
├── 3307
│   ├── data
│   │   ├── ibdata1
│   │   ├── ib_logfile0
│   │   ├── ib_logfile1
│   │   ├── mysql
│   │   ├── mysql.err
│   │   ├── performance_schema
│   │   └── test
│   └── my.cnf
├── 3308
│   ├── data
│   │   ├── ibdata1
│   │   ├── ib_logfile0
│   │   ├── ib_logfile1
│   │   ├── mysql
│   │   ├── mysql.err
│   │   ├── performance_schema
│   │   └── test
│   └── my.cnf
├── 3309
│   ├── data
│   │   ├── ibdata1
│   │   ├── ib_logfile0
│   │   ├── ib_logfile1
│   │   ├── mysql
│   │   ├── mysql.err
│   │   ├── performance_schema
│   │   └── test
│   └── my.cnf
├── mysql -> /service/mysql-5.6.42
└── mysql-5.6.42

5.授权

[root@db02 /service]# chown -R mysql.mysql /service/

6.启动多实例

[root@db02 /service]# mysqld_safe --defaults-file=/service/3307/my.cnf &
[root@db02 /service]# mysqld_safe --defaults-file=/service/3308/my.cnf &
[root@db02 /service]# mysqld_safe --defaults-file=/service/3309/my.cnf &

7.验证启动

[root@db02 /service]# netstat -lntp | grep 330
tcp6       0      0 :::3306                 :::*                    LISTEN      24992/mysqld
tcp6       0      0 :::3307                 :::*                    LISTEN      32069/mysqld 
tcp6       0      0 :::3308                 :::*                    LISTEN      32234/mysqld
tcp6       0      0 :::3309                 :::*                    LISTEN      32394/mysqld

8.登录验证多实例

[root@db02 /service]# mysql -uroot -S /service/3307/data/mysql.sock -e 'show variables like "server_id"'
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| server_id     | 7     |
+---------------+-------+

[root@db02 /service]# mysql -uroot -S /service/3308/data/mysql.sock -e 'show variables like "server_id"'
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| server_id     | 8     |
+---------------+-------+

[root@db02 /service]# mysql -uroot -S /service/3309/data/mysql.sock -e 'show variables like "server_id"'
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| server_id     | 9     |
+---------------+-------+

9.多实例设置密码

[root@db02 /service]# mysqladmin -uroot password -S /service/3307/data/mysql.sock
New password: 123
Confirm new password: 123
[root@db02 /service]# mysqladmin -uroot password -S /service/3308/data/mysql.sock
New password: 123
Confirm new password: 123
[root@db02 /service]# mysqladmin -uroot password -S /service/3309/data/mysql.sock
New password: 123
Confirm new password: 123

10.配置简单连接数据库多实例

#1.编写连接数据库文件
[root@db02 /service]# cat /usr/bin/mysql3307
mysql -uroot -p123 -S /service/3307/data/mysql.sock
[root@db02 /service]# cat /usr/bin/mysql3308
mysql -uroot -p123 -S /service/3308/data/mysql.sock
[root@db02 /service]# cat /usr/bin/mysql3309
mysql -uroot -p123 -S /service/3309/data/mysql.sock

#2.授权执行权限
[root@db02 /service]# chmod +x /usr/bin/mysql*

#3.直接使用命令连接
[root@db02 /service]# mysql3307
[root@db02 /service]# mysql3308
[root@db02 /service]# mysql3309

数据库多实例主从

0）配置主库的binlog

[root@db02 /service]# vim /service/3307/my.cnf 
... ...
log_bin=/service/3307/data/mysql-bin

1.主库授权主从的用户

mysql> grant replication slave on *.* to rep@'172.16.1.%' identified by '123';
Query OK, 0 rows affected (0.00 sec)

2.主库查看binlog信息

mysql> show master status;
+------------------+----------+
| File             | Position |
+------------------+----------+
| mysql-bin.000001 |      120 |
+------------------+----------+
1 row in set (0.01 sec)

3.从库配置同步主库

#1.从库需要知道主库的信息
	1）主库的地址
	2）主库的端口
	3）主库授权的用户
	4）主库授权的用户的密码
	5）主库的binlog日志名字
	6）binlog的位置点
	
#2.从库配置主从同步
mysql> change master to
    -> master_host='172.16.1.52', 
    -> master_port=3307,
    -> master_user='rep',
    -> master_password='123',
    -> master_log_file='mysql-bin.000001',
    -> master_log_pos=120;
Query OK, 0 rows affected, 2 warnings (0.03 sec)

change master to
master_host='172.16.1.52', 
master_port=3309,
master_user='rep',
master_password='123',
master_log_file='mysql-bin.000001',
master_log_pos=120;

4.启动主从同步

mysql> start slave;
Query OK, 0 rows affected (0.00 sec)

5.查看主从状态

mysql> show slave statusG
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 127.0.0.1
                  Master_User: rep
                  Master_Port: 3307
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000001
          Read_Master_Log_Pos: 416
               Relay_Log_File: db02-relay-bin.000002
                Relay_Log_Pos: 579
        Relay_Master_Log_File: mysql-bin.000001
        
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes

6.主从同步问题

1）IO线程为NO

1.检查网络
	[root@db02 ~]# ping 127.0.0.1
2.检查端口
	[root@db02 ~]# telnet 127.0.0.1 3307
3.查看防火墙
4.主从同步的用户和密码错误
	检查change master to语句信息是否正确
5.数据库反向解析

2）SQL线程为NO

1.主库有的数据，从库没有
2.从库有的数据，主库没有
3.主库与从库数据不一致

手动停掉从库 stop slave;

手动同步
 change master to 
 master_host='172.16.1.52',
 master_user='rep', 
 master_password='123', 
 master_port=3309, 
 master_log_file='mysql-bin.000001', 
 master_log_pos=201

启动 start slave

查看