MySQL數據庫入門——多實例配置
前面介紹了相關的基礎命令操作，所有的操作都是基於單實例的，mysql多實例在實際生產環境也是非常實用的，因爲必須要掌握
1、什麼是多實例
多實例就是一臺服務器上開啓多個不同的服務端口（默認3306），運行多個mysql的服務進程，這此服務進程通過不同的socket監聽不同的服務端口來提供各在的服務，所有實例之間共同使用一套MYSQL的安裝程序，但各自使用不同的配置文件、啓動程序、數據文件，在邏輯上是相對獨立的。
多實例主要作用是：充分利用現有的服務器硬件資源，爲不同的服務提供數據服務，但是如果某個實例併發比較高的，同樣是會影響到其它實例的性能
2、安裝多實例環境準備
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），如果使用免安裝程序，只需解壓軟件包即可，今天的環境是通過免安裝包來安裝mysql主程序（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
安裝程序
mysql-5.5.52-linux2.6-x86_64.tar.gz
軟件下載
wget http://mirrors.sohu.com/mysql/MySQL-5.5/mysql-5.5.52-linux2.6-x86_64.tar.gz
創建安裝用戶
[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
創建多實例的數據目錄
[root@centos6 tools]# mkdir -p /data/{3306,3307}
[root@centos6 tools]# tree /data/
/data/
+-- 3306
+-- 3307
2 directories, 0 files
3、安裝MYSQL多實例
接下來進行安裝mysql的多實例操作
解壓軟件
[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
拷貝配置文件
[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
爲一規範安裝路徑，將免安裝包拷貝到應用程序目錄下
[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
修改配置文件與啓動文件
因爲是多實例，其中參數需要修改，修改後的配置文件如下
配置文件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
啓動程序文件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文件進行修改即可
多實例初始化操作
[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，會在數據目錄下產生一個數據目錄data和一些文件
[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
另一個實例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 、啓動多實例並登錄
啓動服務
[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)
檢查端口
[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
登陸多實例數據庫
[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, 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> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| test |
+--------------------+
4 rows in set (0.05 sec)
成功登陸，並在3306實例中創建數據庫，但是3307實例上查看並沒有創建過的數據，說明兩個實例是獨立的
注：如果再需要新增一個實例，基本的配置步驟同上述一樣，只需要相應修改配置文件與啓動程序文件中的端口號與數據目錄的路徑即可，最後可以將多實例數據庫啓動命令加入開機自啓動