本文例項講述了MySQL資料庫入門之多例項配置方法。分享給大家供大家參考，具體如下：

前面介紹了相關的基礎命令操作：MySQL資料庫基礎篇之入門基礎命令

所有的操作都是基於單例項的，mysql多例項在實際生產環境也是非常實用的，因為必須要掌握。

1、什麼是多例項

多例項就是一臺伺服器上開啟多個不同的服務埠（預設3306），執行多個mysql的服務程序，這此服務程序通過不同的socket監聽不同的服務埠來提供各在的服務，所有例項之間共同使用一套MYSQL的安裝程式，但各自使用不同的配置檔案、啟動程式、資料檔案，在邏輯上是相對獨立的。

多例項主要作用是：充分利用現有的伺服器硬體資源，為不同的服務提供資料服務，但是如果某個例項併發比較高的，同樣是會影響到其它例項的效能

2、安裝多例項環境準備

安裝前需要先安裝mysql，但是隻需將安裝過程進行到make install即可（編譯安裝），如果使用免安裝程式，只需解壓軟體包即可，今天的環境是通過免安裝包來安裝mysql主程式（其它的安裝可以參考前面的安裝過程自行測試）

系統環境

[root@centos6 ~]# cat /etc/redhat-release 
CentOS release 6.5 (Final)
[root@centos6 ~]# uname -r
2.6.32-431.el6.x86_64

安裝程式

mysql-5.5.52-linux2.6-x86_64.tar.gz

首先將軟體下載到本地

wget http://mirrors.sohu.com/mysql/MySQL-5.5/mysql-5.5.52-linux2.6-x86_64.tar.gz

建立安裝使用者

[root@centos6 ~]#groupadd mysql
[root@centos6 ~]#useradd mysql -s /sbin/nologin -g mysql -M
[root@centos6 ~]#tail -1 /etc/passwd
mysql:x:500:500::/home/mysql:/sbin/nologin

建立多例項的資料目錄

[root@centos6 tools]# mkdir -p /data/{3306,3307}
[root@centos6 tools]# tree /data/
/data/
+-- 3306
+-- 3307
2 directories,0 files

3、安裝MYSQL多例項

接下來進行安裝mysql的多例項操作

解壓軟體

[root@centos6 tools]# ll mysql-5.5.52-linux2.6-x86_64.tar.gz 
-rw-r--r--. 1 root root 185855000 Aug 26 21:38 mysql-5.5.52-linux2.6-x86_64.tar.gz
[root@centos6 tools]# tar zxf mysql-5.5.52-linux2.6-x86_64.tar.gz

拷貝配置檔案

[root@centos6 mysql-5.5.52-linux2.6-x86_64]# cp support-files/my-small.cnf /data/3306/my.cnf

[root@centos6 mysql-5.5.52-linux2.6-x86_64]# cp support-files/mysql.server /data/3306/mysql

[root@centos6 mysql-5.5.52-linux2.6-x86_64]# cp support-files/my-small.cnf /data/3307/my.cnf

[root@centos6 mysql-5.5.52-linux2.6-x86_64]# cp support-files/mysql.server /data/3307/mysql

為一規範安裝路徑，將免安裝包拷貝到應用程式目錄下

[root@centos6 tools]# mv mysql-5.5.52-linux2.6-x86_64 /application/mysql

[root@centos6 tools]# ll /application/mysql
total 72
drwxr-xr-x. 2 root root 4096 Dec 9 17:15 bin
-rw-r--r--. 1 7161 31415 17987 Aug 26 19:24 COPYING
drwxr-xr-x. 3 root root 4096 Dec 9 17:15 data
drwxr-xr-x. 2 root root 4096 Dec 9 17:15 docs
drwxr-xr-x. 3 root root 4096 Dec 9 17:15 include
-rw-r--r--. 1 7161 31415 301 Aug 26 19:24 INSTALL-BINARY
drwxr-xr-x. 3 root root 4096 Dec 9 17:15 lib
drwxr-xr-x. 4 root root 4096 Dec 9 17:15 man
drwxr-xr-x. 10 root root 4096 Dec 9 17:15 mysql-test
-rw-r--r--. 1 7161 31415 2496 Aug 26 19:24 README
drwxr-xr-x. 2 root root 4096 Dec 9 17:15 scripts
drwxr-xr-x. 27 root root 4096 Dec 9 17:15 share
drwxr-xr-x. 4 root root 4096 Dec 9 17:15 sql-bench
drwxr-xr-x. 2 root root 4096 Dec 9 17:15 support-files

修改配置檔案與啟動檔案

因為是多例項，其中引數需要修改，修改後的配置檔案如下：配置檔案my.cnf

[client]
port = 3307
socket = /data/3307/mysql.sock

[mysql]
no-auto-rehash

[mysqld] user = mysql
port = 3307
socket = /data/3307/mysql.sock
basedir = /application/mysql
datadir = /data/3307/data
#log_long_format
#log-error = /data/3307/error.log
#log-slow-queries = /data/3307/slow.log
pid-file = /data/3307/mysql.pid
server-id = 3 

[mysqld_safe]
log-error=/data/3307/mysql3307.err
pid-file=/data/3307/mysqld.pid

啟動程式檔案mysql

[root@backup 3307]# cat mysql
#!/bin/sh
init port=3307
mysql_user="root"
mysql_pwd="migongge"
CmdPath="/application/mysql/bin"
mysql_sock="/data/${port}/mysql.sock"
#startup
function_start_mysql() {
if [ ! -e "$mysql_sock" ];then
 printf "Starting MySQL...\n"
/bin/sh ${CmdPath}/mysqld_safe --defaults-file=/data/${port}/my.cnf 2>&1 > /dev/null &
else
 printf "MySQL is running...\n"
exit
fi
}
#stop function
function_stop_mysql() {
if [ ! -e "$mysql_sock" ];then
printf "MySQL is stopped...\n"
exit
else
printf "Stoping MySQL...\n"
${CmdPath}/mysqladmin -u ${mysql_user} -p${mysql_pwd} -S /data/${port}/mysql.sock shutdown
fi
}
#restart function
function_restart_mysql() {
 printf "Restarting MySQL...\n"
 function_stop_mysql
 sleep 2
 function_start_mysql
}
case $1 in
start)
function_start_mysql
;;
stop)
function_stop_mysql
;;
restart)
function_restart_mysql
;;
*)
printf "Usage: /data/${port}/mysql {start|stop|restart}\n"
esac

其它的配置可參考配置檔案進行修改即可

多例項初始化操作

[root@centos6 3306]# /application/mysql/scripts/mysql_install_db --basedir=/application/mysql --datadir=/data/3306/data --user=mysql
Installing MySQL system tables...
161209 18:02:17 [Warning] 'THREAD_CONCURRENCY' is deprecated and will be removed in a future release.
161209 18:02:17 [Note] /application/mysql/bin/mysqld (mysqld 5.5.52-log) starting as process 3336 ...
OK
Filling help tables...
161209 18:02:17 [Warning] 'THREAD_CONCURRENCY' is deprecated and will be removed in a future release.
161209 18:02:17 [Note] /application/mysql/bin/mysqld (mysqld 5.5.52-log) starting as process 3343 ...
OK
To start mysqld at boot time you have to copy
support-files/mysql.server to the right place for your system
PLEASE REMEMBER TO SET A PASSWORD FOR THE MySQL root USER !
To do so,start the server,then issue the following commands:
/application/mysql/bin/mysqladmin -u root password 'new-password'
/application/mysql/bin/mysqladmin -u root -h centos6 password 'new-password'
Alternatively you can run:
/application/mysql/bin/mysql_secure_installation
which will also give you the option of removing the test
databases and anonymous user created by default. This is
strongly recommended for production servers.
See the manual for more instructions.
You can start the MySQL daemon with:
cd /application/mysql ; /application/mysql/bin/mysqld_safe &
You can test the MySQL daemon with mysql-test-run.pl
cd /application/mysql/mysql-test ; perl mysql-test-run.pl
Please report any problems at http://bugs.mysql.com/

初始化成功後，會在資料目錄下產生一個數據目錄data和一些檔案

[root@centos6 3306]# ll /data/3306/data/
total 1136
drwx------. 2 mysql root  4096 Dec 9 18:02 mysql
-rw-rw----. 1 mysql mysql 27693 Dec 9 18:02 mysql-bin.000001
-rw-rw----. 1 mysql mysql 1114546 Dec 9 18:02 mysql-bin.000002
-rw-rw----. 1 mysql mysql  38 Dec 9 18:02 mysql-bin.index
drwx------. 2 mysql mysql 4096 Dec 9 18:02 performance_schema
drwx------. 2 mysql root  4096 Dec 9 18:02 test

另一個例項的初始化請參考上述操作進行，操作過程不再一一介紹

[root@centos6 3307]# ll /data/3307/data/
total 1136
drwx------. 2 mysql root  4096 Dec 9 18:40 mysql
-rw-rw----. 1 mysql mysql 27693 Dec 9 18:40 mysql-bin.000001
-rw-rw----. 1 mysql mysql 1114546 Dec 9 18:40 mysql-bin.000002
-rw-rw----. 1 mysql mysql  38 Dec 9 18:40 mysql-bin.index
drwx------. 2 mysql mysql 4096 Dec 9 18:40 performance_schema
drwx------. 2 mysql root  4096 Dec 9 18:40 test

4 、啟動多例項並登入

啟動服務

[root@backup 3307]# /data/3306/mysql start
Starting MySQL...
[root@backup 3307]# lsof -i :3306
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
mysqld 19986 mysql 10u IPv4 90967 0t0 TCP *:mysql (LISTEN)
[root@backup 3307]# /data/3307/mysql
start Starting MySQL...
[root@backup 3307]# lsof -i :3307
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
mysqld 21648 mysql 11u IPv4 92899 0t0 TCP *:opsession-prxy (LISTEN)

檢查埠

[root@backup 3307]# netstat -lntup|grep mysql
tcp 0 0 0.0.0.0:3307 0.0.0.0:* LISTEN 21648/mysqld
tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN 19986/mysqld

登陸多例項資料庫

[root@backup ~]# mysql -S /data/3306/mysql.sock
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.5.51-log Source distribution
Copyright (c) 2000,2016,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 data3306;
Query OK,1 row affected (0.00 sec)
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| data3306 |
| mysql |
| performance_schema |
| test |
+--------------------+
5 rows in set (0.00 sec)
mysql> quit
Bye

[root@backup ~]# mysql -S /data/3307/mysql.sock
Welcome to the MySQL monitor.
Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.5.51 Source distribution
Copyright (c) 2000,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> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| test |
+--------------------+
4 rows in set (0.05 sec)

成功登陸，並在3306例項中建立資料庫，但是3307例項上檢視並沒有建立過的資料，說明兩個例項是獨立的

注：如果再需要新增一個例項，基本的配置步驟同上述一樣，只需要相應修改配置檔案與啟動程式檔案中的埠號與資料目錄的路徑即可，最後可以將多例項資料庫啟動命令加入開機自啟動。

更多關於MySQL相關內容感興趣的讀者可檢視本站專題：《MySQL查詢技巧大全》、《MySQL常用函式大彙總》、《MySQL日誌操作技巧大全》、《MySQL事務操作技巧彙總》、《MySQL儲存過程技巧大全》及《MySQL資料庫鎖相關技巧彙總》

希望本文所述對大家MySQL資料庫計有所幫助。