mysql多实例（mysqld_multi方式）-Mysql数据库总结

CleverCode最近在研究mysql的多实例，发现有两种方式：

第一种是使用多个配置文件启动不同的进程来实现多实例。这种方式的优势逻辑简单，配置简单，缺点是管理起来不太方便。

第二种是通过官方自带的mysqld_multi。使用单独的配置文件来实现多实例，这种方式定制每个实例的配置不太方面，优点是管理起来很方便，集中管理。

推荐使用多个配置文件方式。这种实际应用中好，耦合性不强，配置方便，特别是主从复制的时候。

上一篇《mysql多实例（多个配置文件方式）》：http://blog.csdn.net/clevercode/article/details/47610619。介绍了多个配置文件方式。本篇将介绍mysqld_multi方式。

1 环境介绍：

1）简介
mysql 版本：mysql-5.5.27
cmake：cmake-2.8.8
操作系统：CentOS6.5
mysql实例数：3个
实例占用端口分别为：3306、3307、3308

2）本次安装所有的软件资源包下载地址
http://download.csdn.net/detail/clevercode/8662323

2 配置防火墙
1) 在防火墙配置文件中添加3306，3307,3308（允许3306，3307,3308端口通过防火墙）

 # vi /etc/sysconfig/iptables   #编辑防火墙配置文件   
-A INPUT -m state --state NEW -m tcp -p tcp --dport 3306 -j ACCEPT  
-A INPUT -m state --state NEW -m tcp -p tcp --dport 3307 -j ACCEPT  
-A INPUT -m state --state NEW -m tcp -p tcp --dport 3308 -j ACCEPT

2）重启防火墙

 # /etc/init.d/iptables restart  #最后重启防火墙使配置生效

3 安装cmake
解压

 # cd /usr/local/src/mysql  
 # tar zxvf cmake-2.8.8.tar.gz  
 # cd cmake-2.8.8

配置
# ./configure

编译
# make

安装
# make install

查看版本
# cmake -version

4 安装Mysql
1) 创建用户

 # groupadd mysql  #添加mysql组      
 # useradd -g mysql mysql -s /bin/false  #创建用户mysql并加入到mysql组，不允许mysql用户直接登录系统

2) 解压

 # cd /usr/local/src/mysql  
 # tar zxvf mysql-5.5.27.tar.gz  
 # cd mysql-5.5.27

4) 配置
# cmake . -DCMAKE_INSTALL_PREFIX=/usr/local/mysql

PS: cmake的时候，参数可以不用那么多，只要一个-DCMAKE_INSTALL_PREFIX=/usr/local/mysql就行了，我们可以在 my.cnf里面配置。[mysqld]中的内容，看看你copy后的my.cnf有没有这些设置，有就不用了在设置了。

5）编译
# make

6)安装
# make install

5 初始化数据库

 # mkdir -p /data0/dbdata/mysql/3306  
 # mkdir -p /data0/dbdata/mysql/3307  
 # mkdir -p /data0/dbdata/mysql/3308  
  
 # chown -R mysql:mysql /data0/dbdata/mysql/3306  
 # chown -R mysql:mysql /data0/dbdata/mysql/3307  
 # chown -R mysql:mysql /data0/dbdata/mysql/3308  
  
 # /usr/local/mysql/scripts/mysql_install_db --basedir=/usr/local/mysql --datadir=/data0/dbdata/mysql/3306 --user=mysql  
 # /usr/local/mysql/scripts/mysql_install_db --basedir=/usr/local/mysql --datadir=/data0/dbdata/mysql/3307 --user=mysql  
 # /usr/local/mysql/scripts/mysql_install_db --basedir=/usr/local/mysql --datadir=/data0/dbdata/mysql/3308 --user=mysql

6 修改配置文件（只用/etc/my.cnf文件）

 # cp /usr/local/mysql/support-files/my-huge.cnf /etc/my.cnf
 # vi /etc/my.cnf

[mysqld_multi] 
mysqld = /usr/local/mysql/bin/mysqld_safe 
mysqladmin = /usr/local/mysql/bin/mysqladmin 

 #用于登陆和关闭此服务
user       = root
password   = CleverCode123

[mysqld3306] 
 #数据目录
datadir = /data0/dbdata/mysql/3306

 #连接 
port = 3306 
socket = /tmp/mysql3306.sock
 
 #binlog 
log-bin=/data0/dbdata/mysql/3306/mysql-bin 

pid-file = /data0/dbdata/mysql/3306/mysql_3306.pid

[mysqld3307] 
datadir = /data0/dbdata/mysql/3307
port = 3307
socket = /tmp/mysql3307.sock 
log-bin=/data0/dbdata/mysql/3307/mysql-bin 
pid-file = /data0/dbdata/mysql/3307/mysql_3307.pid

[mysqld3308] 
datadir = /data0/dbdata/mysql/3308
port = 3308
socket = /tmp/mysql3308.sock
log-bin=/data0/dbdata/mysql/3308/mysql-bin
pid-file = /data0/dbdata/mysql/3308/mysql_3308.pid

7 启动3306、3307、3308的mysql

 # /usr/local/mysql/bin/mysqld_multi start 3306  
 # /usr/local/mysql/bin/mysqld_multi start 3307  
 # /usr/local/mysql/bin/mysqld_multi start 3308

8 查看端口是否监听，如果出现3306,3307,3308则启动正常

 # netstat -anp | grep 3308  
  
tcp        0      0 0.0.0.0:3308                0.0.0.0:*                   LISTEN      2348/mysqld           
unix  2      [ ACC ]     STREAM     LISTENING     10780  2348/mysqld         /tmp/mysql3308.sock

9 初始化密码并且授权远程登录，mysqladmin用户名和密码需要和/ect/my.cnf中保持一致，否则stop不了服务。

 # /usr/local/mysql/bin/mysqladmin -u root password "CleverCode123" -S /tmp/mysql3306.sock  
 # /usr/local/mysql/bin/mysql -uroot -pCleverCode123 -S  /tmp/mysql3306.sock  
mysql> grant all privileges on  *.* to "root"@"%" identified by "pwd3306" with grant option;  
mysql> flush privileges;  
  
 # /usr/local/mysql/bin/mysqladmin -u root password "CleverCode123" -S /tmp/mysql3307.sock  
 # /usr/local/mysql/bin/mysql -uroot -pCleverCode123 -S  /tmp/mysql3307.sock  
mysql> grant all privileges on  *.* to "root"@"%" identified by "pwd3307" with grant option;  
mysql> flush privileges;  
  
 # /usr/local/mysql/bin/mysqladmin -u root password "CleverCode123" -S /tmp/mysql3308.sock  
 # /usr/local/mysql/bin/mysql -uroot -pCleverCode123 -S  /tmp/mysql3308.sock  
mysql> grant all privileges on  *.* to "root"@"%" identified by "pwd3308" with grant option;  
mysql> flush privileges;

10 停止（必须先初始化密码）。可以使用netstat -anp | grep 3308查看监听进程是否还存在

 # /usr/local/mysql/bin/mysqld_multi stop 3306  
 # /usr/local/mysql/bin/mysqld_multi stop 3307  
 # /usr/local/mysql/bin/mysqld_multi stop 3308

11 报告。显示进程的状态

 # /usr/local/mysql/bin/mysqld_multi report 3306  
 # /usr/local/mysql/bin/mysqld_multi report 3307  
 # /usr/local/mysql/bin/mysqld_multi report 3308