CentOS安装两个MYSQL5.7.21

项目上正式是MySQL5.7.21-log版本，但是本地测试是使用的MySQL5.7.22，蛋疼的客户非得统一版本，本着学习的精神，自己折腾了一天、

于是把测试数据库也撞上了MySQL5.7.21

第一步 下载:mysql-5.7.21-linux-glibc2.12-x86_64

第二步 上传、解压mysql-5.7.21-linux-glibc2.12-x86_64 ,使用tar -xvf mysql-5.7.21-linux-glibc2.12-x86_64，将解压的文件重命名并移到/usr/local

第三步 在mysql-5.7下新增文件夹data,var,etc备用

第四步 创建数据库配置文件，如果在/etc（不是自己创建的）下有my.cnf则修改，如果没有则touch新建

# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/5.7/en/server-configuration-defaults.html
# *** DO NOT EDIT THIS FILE. It‘s a template which will be copied to the
# *** default location during install, and will be replaced if you
# *** upgrade to a newer version of MySQL.

[mysqld]

# Remove leading # and set to the amount of RAM for the most important data
# cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%.
# innodb_buffer_pool_size = 128M

# Remove leading # to turn on a very important data integrity option: logging
# changes to the binary log between backups.
# log_bin

# These are commonly set, remove the # and set as required.
# /usr/local/mysql5721/mysql-5.7.21是解压之后的文件夹
basedir=/usr/local/mysql5721/mysql-5.7.21
datadir =/usr/local/mysql5721/mysql-5.7.21/data
port = 5723
log-error = /usr/local/mysql5721/mysql-5.7.21/data/error.log

pid-file = /usr/local/mysql5721/mysql-5.7.21/data/mysql.pid

socket = /usr/local/mysql5721/mysql-5.7.21/mysql.sock

# Remove leading # to set options mainly useful for reporting servers.
# The server defaults are faster for transactions and fast SELECTs.
# Adjust sizes as needed, experiment to find the optimal values.
# join_buffer_size = 128M
# sort_buffer_size = 2M
# read_rnd_buffer_size = 2M 

#sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES 
[client]
socket = /usr/local/mysql5721/mysql-5.7.21/mysql.sock

　　第五步改变文件夹权限，使得mysql可以访问

#groupadd mysql2
#useradd mysql2-g mysql2
#chown -R mysql2:mysql2 mysql-5.7.21/
#chmod -R 777 mysql-5.7.21/

　　第六步

　　指定配置文件初始化

 ./bin/mysqld --defaults-file=/usr/local/mysql5721/mysql-5.7.21/etc/my.cnf --initialize --user=mysql2 --socket = /tmp/mysql5721.socket --port=5721

　　查询默认密码

　　

cat /usr/local/mysql5721/mysql5.7.21/data/error.log

　　generated for root@localhost后面就是默认生成的密码

第七步

　　启动mysql,执行 ./support-files/mysql.server start

第八步

　　修改密码配置权限，打开Navicat连接

问题以及参考文章

MYSQL多数据库安装

https://blog.csdn.net/u010898329/article/details/83064373

MYSQL安装后一些问题

解决Navicat 报错:1130-host is not allowed MySQL不允许从远程访问的方法

https://www.cnblogs.com/mengyuxin/p/5485143.html

You must reset your password using ALTER USER statement before executing this statement.

https://www.cnblogs.com/debmzhang/p/5013540.html

MySQL添加用户、删除用户与授权

 https://www.cnblogs.com/wanghetao/p/3806888.html

送给自己一句话

　　

我愿意给你当狗，你不要，你怕我咬你，结果我成了龙了

　　　　　　　　　　　　　　　　　　　　　　　　　　——郭德纲