mysql5.7 single multi-instance installation

Installation based on the previous single instance mysql5.7

Modify /etc/my.cnffollowing documents (4 instances where configuration may be modified self-number)

#
# 多实例配置文件，可以mysqld_multi --example 查看例子
#
[root@MyServer /]> cat /etc/my.cnf 
#[client]           # 这个标签如果配置了用户和密码，
                    # 并且[mysqld_multi]下没有配置用户名密码，
                    # 则mysqld_multi stop时, 会使用这个密码
                    # 如果没有精确的匹配，则匹配[client]标签
#user = root        
#password = 123
#-------------
[mysqld_multi]
mysqld = /usr/local/mysql/bin/mysqld_safe
mysqladmin = /usr/local/mysql/bin/mysqladmin
user = multi_admin
pass = 123  # 官方文档中写的password，但是存在bug，需要改成pass(v5.7.9)
            # 写成password，start时正常，stop时，报如下错误
            # Access denied for user 'multi_admin'@'localhost' (using password: YES)
log = /var/log/mysqld_multi.log


[mysqld1]            
server-id = 11
socket = /tmp/mysql.sock1
port = 3306
bind_address = 0.0.0.0
datadir = /data1
user = mysql
performance_schema = off
innodb_buffer_pool_size = 32M
skip_name_resolve = 1
log_error = error.log
pid-file = /data1/mysql.pid1


[mysqld2]
server-id = 12
socket = /tmp/mysql.sock2
port = 3307
bind_address = 0.0.0.0
datadir = /data2
user = mysql
performance_schema = off
innodb_buffer_pool_size = 32M
skip_name_resolve = 1
log_error = error.log
pid-file = /data2/mysql.pid2


[mysqld3]
server-id = 13
socket = /tmp/mysql.sock3
port = 3308
bind_address = 0.0.0.0
datadir = /data3
user = mysql
performance_schema = off
innodb_buffer_pool_size = 32M
skip_name_resolve = 1
log_error = error.log
pid-file = /data3/mysql.pid3


[mysqld4]
server-id = 14
socket = /tmp/mysql.sock4
port = 3309
bind_address = 0.0.0.0
datadir = /data4
user = mysql
performance_schema = off
innodb_buffer_pool_size = 32M
skip_name_resolve = 1
log_error = error.log
pid-file = /data4/mysql.pid4

---

Ready data directory, and the initial installation

[root@MyServer ~]> mkdir /data1
[root@MyServer ~]> mkdir /data2
[root@MyServer ~]> mkdir /data3
[root@MyServer ~]> mkdir /data4
[root@MyServer ~]> chown mysql.mysql /data{1..4}
[root@MyServer ~]> mysqld --initialize --user=mysql --datadir=/data1
#
# 一些日志输出，并提示临时密码，下同
#
[root@MyServer ~]> mysqld --initialize --user=mysql --datadir=/data2
[root@MyServer ~]> mysqld --initialize --user=mysql --datadir=/data3
[root@MyServer ~]> mysqld --initialize --user=mysql --datadir=/data4  

# 安装后，需要检查error.log 确保没有错误出现
[root@MyServer ~]> cp /usr/local/mysql/support-files/mysqld_multi.server  /etc/init.d/mysqld_multid 
# 拷贝启动脚本，方便自启
[root@MyServer ~]> chkconfig mysqld_multid on  

[root@MyServer ~]> mysqld_multi  start
[root@MyServer ~]> mysqld_multi  report
Reporting MySQL servers
MySQL server from group: mysqld1 is running
MySQL server from group: mysqld2 is running
MySQL server from group: mysqld3 is running
MySQL server from group: mysqld4 is running
[root@MyServer ~]> netstat -tunlp | grep mysql
[root@MyServer ~]> netstat -tunlp | grep mysql
tcp        0      0 :::3307                     :::*                        LISTEN      6221/mysqld         
tcp        0      0 :::3308                     :::*                        LISTEN      6232/mysqld         
tcp        0      0 :::3309                     :::*                        LISTEN      6238/mysqld         
tcp        0      0 :::3306                     :::*                        LISTEN      6201/mysqld         

[root@MyServer ~]> mysql -u root -S /tmp/mysql.sock1 -p -P3306
#
# 使用-S /tmp/mysql.sock1 进行登录，并输入临时密码后，修改密码，下同
#
[root@MyServer ~]> mysql -u root -S /tmp/mysql.sock2 -p -P3307
[root@MyServer ~]> mysql -u root -S /tmp/mysql.sock3 -p -P3308
[root@MyServer ~]> mysql -u root -S /tmp/mysql.sock4 -p -P3309
#输入临时密码,开始修改密码

#MySQL版本5.7.6版本以前用户可以使用如下命令：
mysql> SET PASSWORD = PASSWORD('123456'); 

#MySQL版本5.7.6版本开始的用户可以使用如下命令：
mysql> ALTER USER USER() IDENTIFIED BY '123456';  

--
-- mysql1
--
mysql> show variables like "port"; 
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| port          | 3306  |
+---------------+-------+
1 row in set (0.00 sec)

mysql> show variables like "socket";
+---------------+------------------+
| Variable_name | Value            |
+---------------+------------------+
| socket        | /tmp/mysql.sock1 |
+---------------+------------------+
1 row in set (0.01 sec)

mysql> show variables like "datadir";
+---------------+---------+
| Variable_name | Value   |
+---------------+---------+
| datadir       | /data1/ |
+---------------+---------+
1 row in set (0.00 sec)
   
--
-- mysql2, mysql3, mysql4 类似。可以看到与my.cnf中对应的port和socket
--

## 关闭数据库(mysqld_multi stop 好像不起作用)
pkill -9 mysql  

If you use mysqld_multi report found that the configuration of the database instance is not running, review the configuration datadir in the error log, if there is no error log, you can delete the files in the datadir, check for errors in the my.cnf, re-execute the initialization