MYSQL小版本升级（5.7.21至5.7.25）

1.环境确认

[root@mysql ~]# ps -ef |grep -i mysql
root 9173 1 0 2020 ? 00:00:00 /bin/sh /mysql/data/mysql-5.7.21/bin/mysqld_safe --datadir=/mysql/data/mysql-5.7.21/data --pid-file=/mysql/data/mysql-5.7.21/data/mysqld.pid
mysql 9367 9173 0 2020 ? 06:07:52 /mysql/data/mysql-5.7.21/bin/mysqld --basedir=/mysql/data/mysql-5.7.21 --datadir=/mysql/data/mysql-5.7.21/data --plugin-dir=/mysql/data/mysql-5.7.21/lib/plugin --user=mysql --log-error=/mysql/data/mysql-5.7.21/data/mysqld.log --pid-file=/mysql/data/mysql-5.7.21/data/mysqld.pid --socket=/tmp/mysql.sock --port=3306
root 17045 17002 0 09:36 pts/0 00:00:00 grep --color=auto -i mysql

mysql -uroot -pmysql@2020

mysql -e "SELECT table_schema,SUM(data_length+index_length)/1024/1024 AS total_mb,SUM(data_length)/1024/1024 AS data_mb,SUM(index_length)/1024/1024 AS index_mb, SUM(data_free)/1024/1024 AS free_mb,COUNT(*) AS tables_num,CURDATE() AS today FROM information_schema.tables where table_schema not in ('mysql','sys','information_schema','performance_schema') GROUP BY table_schema ORDER BY total_mb desc\G"
*************************** 1. row ***************************
table_schema: app_manager
total_mb: 153.42434692
data_mb: 138.15676880
index_mb: 15.26757813
free_mb: 14.00000000
tables_num: 19
today: 2021-06-07
*************************** 2. row ***************************
table_schema: lifeapp_config
total_mb: 0.14376068
data_mb: 0.11055756
index_mb: 0.03320313
free_mb: 0.00000000
tables_num: 8
today: 2021-06-07
2 rows in set (0.01 sec)

=============================

2.新环境准备

mkdir -p /mysql/data/mysql-5.7.25/data
chown -R mysql:mysql /mysql/data/mysql-5.7.25/
chmod 750 /mysql/data/mysql-5.7.25/

cd /mysql/data/
tar -zxf mysql-5.7.25-linux-glibc2.12-x86_64.tar.gz
mv mysql-5.7.25-linux-glibc2.12-x86_64 mysql-5.7.25
chown -R mysql.mysql mysql-5.7.25

3.关闭原环境

tail -100f /mysql/data/mysql-5.7.21/data/mysqld.log
/mysql/data/mysql-5.7.21/bin/mysqladmin -uroot -p'mysql@2020' shutdown

cp /etc/my.cnf /etc/my.cnf.07bak
cp -rp /mysql/data/mysql-5.7.21/data/* /mysql/data/mysql-5.7.25/data/

4.启动新环境

/mysql/data/mysql-5.7.25/mysql-5.7.25-linux-glibc2.12-x86_64/bin/mysqld --basedir=/mysql/data/mysql-5.7.25 --datadir=/mysql/data/mysql-5.7.25/data --plugin-dir=/mysql/data/mysql-5.7.25/mysql-5.7.25-linux-glibc2.12-x86_64/lib/plugin --user=mysql --log-error=/mysql/data/mysql-5.7.25/data/mysqld.log --pid-file=/mysql/data/mysql-5.7.25/data/mysqld.pid --socket=/tmp/mysql.sock --port=3306 --skip-grant-tables --skip-networking &

5.升级数据字典

/mysql/data/mysql-5.7.25/mysql-5.7.25-linux-glibc2.12-x86_64/bin/mysql_upgrade -S /tmp/mysql.sock

/mysql/data/mysql-5.7.25/mysql-5.7.25-linux-glibc2.12-x86_64/bin/mysqladmin -S /tmp/mysql.sock -uroot -p'mysql@2020' shutdown

6.修改环境变量

vi /etc/profile
PATH=$PATH:/mysql/data/mysql-5.7.21/bin
改为
PATH=$PATH:/mysql/data/mysql-5.7.25/mysql-5.7.25-linux-glibc2.12-x86_64/bin

退出重新登陆加载环境变量并确认：
which mysql

7.修改参数文件

vi /etc/my.cnf
[mysqld]
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES

basedir = /mysql/data/mysql-5.7.25
datadir = /mysql/data/mysql-5.7.25/data
port = 3306
socket = /tmp/mysql.sock
character-set-server=utf8

log-error = /mysql/data/mysql-5.7.25/data/mysqld.log
pid-file = /mysql/data/mysql-5.7.25/data/mysqld.pid

8.启动环境

/mysql/data/mysql-5.7.25/mysql-5.7.25-linux-glibc2.12-x86_64/bin/mysqld_safe --datadir=/mysql/data/mysql-5.7.25/data --pid-file=/mysql/data/mysql-5.7.25/data/mysqld.pid &

9.检查确认

cat /etc/my.cnf

mysql -uroot -pmysql@2020
[root@mysql ~]# mysql -uroot -pmysql@2020
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 4
Server version: 5.7.25 MySQL Community Server (GPL)

Copyright (c) 2000, 2019, 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> SELECT table_schema,SUM(data_length+index_length)/1024/1024 AS total_mb,SUM(data_length)/1024/1024 AS data_mb,SUM(index_length)/1024/1024 AS index_mb, SUM(data_free)/1024/1024 AS free_mb,COUNT(*) AS tables_num,CURDATE() AS today FROM information_schema.tables where table_schema not in ('mysql','sys','information_schema','performance_schema') GROUP BY table_schema ORDER BY total_mb desc\G
*************************** 1. row ***************************
table_schema: app_manager
total_mb: 153.42434692
data_mb: 138.15676880
index_mb: 15.26757813
free_mb: 10.00000000
tables_num: 19
today: 2021-06-07
*************************** 2. row ***************************
table_schema: lifeapp_config
total_mb: 0.14376068
data_mb: 0.11055756
index_mb: 0.03320313
free_mb: 0.00000000
tables_num: 8
today: 2021-06-07
2 rows in set (0.01 sec)

总结：
1.升级前检查库的角色（主从），数据量的大小。数据量大可以采用这种方式，数据量小可以使用mysqldump进行导出导入。
2.升级重点就是执行新版本的初始化和upgrade脚本检查。
3.本次环境安装不标准，环境变量和my.cnf文件为聚堆全路径，所以需要修改这两项。规范安装应该建立软连接（ln -s mysql-5.7 /full_path ），无需进行修改。