MySQL5.7 多實例

文中使用mysql5.7 版本實現多實例，端口爲3306和3307。

一、多實例本質
在一臺機器上開啓多個不一樣的mysql服務端口（3306,3307），運行多個mysql服務進程，這些服務進程經過不一樣的socket監聽不一樣的服務端口來提供各自的服務；

多個實例共用一套mysql安裝程序，配置文件能夠用同一個（可是最好不一樣，文中用不一樣配置文件），啓動程序能夠用同一個（最好不一樣，文本用不一樣啓動腳本），數據文件是不一樣的（必須不一樣）；

服務器的硬件資源是公用的，邏輯上多實例是各自獨立的；

二、多實例做用
有效利用服務器資源；節約服務器資源；
可是多實例確定會存在資源互相搶佔問題，當某個服務實例併發很高或者有慢查詢時，會消耗整臺服務器更多的內存、CPU等，勢必致使其餘實例運行也很慢。

三、多實例應用場景
資金比較緊張的公司；
併發訪問不是特別大的業務；

四、安裝多實例數據庫

1.建立相應的目錄

mkdir /mysql/{3306,3307}/{data,logs,conf,tmp} -p

// 目錄解釋
data  # 存放數據 logs # 存放mysql日誌以及binlog日誌 conf # 存放mysql配置文件 tmp # 存放mysql socket文件

2.建立mysql用戶，登陸方式nologin，不建立家目錄

groupadd mysql -g 1002
useradd mysql -u 1002 -g 1002 -s /sbin/nologin -M

3.安裝一些依賴包

yum install ncurses-devel libaio-devel -y

4.上傳mysql 5.7至本機/application目錄

// 將mysql5.7 解壓並移動到/application/mysql-5.7.20 目錄下
mkdir -p /application/mysql-5.7.20 
tar xf mysql-5.7.20-linux-glibc2.12-x86_64.tar.gz ./mysql-5.7.20
mv mysql-5.7.20-linux-glibc2.12-x86_64/* mysql-5.7.20/
rm -rf mysql-5.7.20-linux-glibc2.12-x86_64

// 軟鏈接
ln -s /application/mysql-5.7.20/ /application/mysql // 將 /application/mysql/bin 目錄加入PATH環境變量 vim /etc/profile export MYSQL_HOME=/application/mysql/bin export PATH=$PATH:$MYSQL_HOME

5.每一個實例配置my.cnf文件

3306實例

# vim /mysql/3306/conf/my.cnf [mysqld] basedir=/application/mysql datadir=/mysql/3306/data tmpdir = /mysql/3306/tmp socket=/mysql/3306/tmp/mysql.sock log-error=/mysql/3306/logs/mysql.log port=3306 server_id=3306 max_connections = 1000 innodb_buffer_pool_size = 260M skip_name_resolve # 字符集 character-set-server = utf8mb4 collation-server = utf8mb4_general_ci nit_connect='SET NAMES utf8mb4' # bin-log日誌 log-bin=/mysql/3306/data/mysql-bin binlog_format=row # 慢日誌 slow_query_log = 1 slow_query_log_file = /mysql/3306/logs/slow.log log_queries_not_using_indexes = 1 log_throttle_queries_not_using_indexes = 5 long_query_time = 1 [mysql] socket=/mysql/3306/tmp/mysql.sock [mysqladmin] socket=/mysql/3306/tmp/mysql.sock

3307實例

# vim /mysql/3307/conf/my.cnf [mysqld] basedir=/application/mysql datadir=/mysql/3307/data tmpdir = /mysql/3307/tmp socket=/mysql/3307/tmp/mysql.sock log-error=/mysql/3307/logs/mysql.log port=3307 server_id=3307 max_connections = 1000 innodb_buffer_pool_size = 260M skip_name_resolve # 字符集 character-set-server = utf8mb4 collation-server = utf8mb4_general_ci # bin-log日誌 log-bin=/mysql/3307/data/mysql-bin binlog_format=row # 慢日誌 slow_query_log = 1 slow_query_log_file = /mysql/3307/logs/slow.log log_queries_not_using_indexes = 1 log_throttle_queries_not_using_indexes = 5 long_query_time = 1 [mysql] socket=/mysql/3307/tmp/mysql.sock [mysqladmin] socket=/mysql/3307/tmp/mysql.sock

6.使用mysqld命令初始化mysql數據庫文件

// 受權mysql用戶管理相應的mysql目錄
chown -R mysql:mysql /mysql/

// 初始化多實例
mysqld  --defaults-file=/mysql/3306/conf/my.cnf  --basedir=/application/mysql  --initialize-insecure --user=mysql

mysqld  --defaults-file=/mysql/3307/conf/my.cnf  --basedir=/application/mysql  --initialize-insecure --user=mysql

7.經過mysqld_safe命令啓動多實例mysql

mysqld_safe --defaults-file=/mysql/3306/conf/my.cnf &
mysqld_safe --defaults-file=/mysql/3307/conf/my.cnf &

8.檢查操做

// 查看進程是否存在
ps -ef | grep mysql | grep -v "grep" // 查看端口是否存在 ss -lntup | grep -E "3306|3307" // 本地登陸（-S 指定不一樣實例的socket） mysql -uroot -p -S /mysql/3306/tmp/mysql.sock

9.多實例啓動腳本

#!/bin/bash PORT=3306 SOCK_FILE_LOCK=/mysql/${PORT}/tmp/mysql.sock.lock # start function func_start(){ if [ -f ${SOCK_FILE_LOCK} ];then echo "MySQL ${PORT} has started..." exit 1 else echo "MySQL ${PORT} is start..." mysqld_safe --defaults-file=/mysql/3306/conf/my.cnf >/dev/null & result=$? [ ${result} -ne 0 ] && echo "MySQL ${PORT} start failed..." || echo "MySQL ${PORT} start success.." fi } # stop function func_stop(){ if [ -f ${SOCK_FILE_LOCK} ];then echo "MySQL ${PORT} is stop..." kill $(cat /mysql/${PORT}/tmp/mysql.sock.lock) count=0 while [ $count -ne 60 ] do ((count++)) # echo $count sleep 1 if [ ! -f ${SOCK_FILE_LOCK} ];then echo "MySQL ${PORT} stop success..." break else echo "MySQL ${PORT} is stop..." fi done else echo "MySQL ${PORT} don't start..." exit 1 fi } case $1 in start) func_start;; stop) func_stop;; restart) func_stop sleep 3 func_start echo "MySQL ${PORT} restart success...";; esac

只須要將PORT變量進行替換便可