Article directory
- 1. Software selection and download
- 2. Uninstall mysql8.0
-
- 1. View the deployment information in my.cnf
- 2. Uninstall mysql8.0
- 3. Delete relevant data after uninstalling the installation package
- 3. Installation of mysql5.7
-
- 1. Unzip the installation package
- 2. Initialize the mysql database
- 3. Modify the root password
- Fourth, install the mysql5.7 client
- Attachment: create database and user
This case is to uninstall mysql8.0 and then install mysql5.7
Because the mysql database is reinstalled this time, there is no need to recreate the MySQL user and my.cnf file
1. Software selection and download
Download address: https://dev.mysql.com/downloads/mysql/5.7.html
2. Uninstall mysql8.0
1. Check the deployment information in my.cnf
[root@i-orwnzsqu etc]# cat my.cnf [mysqld] bind-address=0.0.0.0 port=3306 user=zysjswjw basedir=/usr/local/mysql datadir=/data/mysql socket=/tmp/mysql.sock #socket=/var/lib/mysql/mysql.sock log-error=/data/mysql/mysql.err pid-file=/data/mysql/mysql.pid #character config character_set_server=utf8MB4 symbolic-links=0 explicit_defaults_for_timestamp=true [client] socket=/tmp/mysql.sock default-character-set=utf8 [root@i-orwnzsqu etc]#
2. Uninstall mysql8.0
#stop mysql service [root@i-orwnzsqu mysql]# sudo service mysql stop Shutting down MySQL....SUCCESS! [root@i-orwnzsqu mysql]# #Uninstall mysql related installation packages [root@i-orwnzsqu mysql]# sudo yum remove mysql mysql-server mysql-libs mysql-devel mysql-client Resolving Dependencies --> Running transaction check ---> Package mysql-community-client.x86_64 0:8.0.32-1.el7 will be erased ---> Package mysql-community-libs.x86_64 0:8.0.32-1.el7 will be erased --> Processing Dependency: mysql-community-libs(x86-64) >= 5.7.9 for package: mysql-community-libs-compat-5.7.13-1.el7.x86_64 --> Running transaction check ---> Package mysql-community-libs-compat.x86_64 0:5.7.13-1.el7 will be erased --> Processing Dependency: libmysqlclient.so.18()(64bit) for package: php56w-mysql-5.6.23-1.w7.x86_64 --> Processing Dependency: libmysqlclient.so.18()(64bit) for package: zabbix-proxy-mysql-3.0.3-1.el7.x86_64 --> Processing Dependency: libmysqlclient.so.18()(64bit) for package: 2:postfix-2.10.1-6.el7.x86_64 --> Processing Dependency: libmysqlclient.so.18()(64bit) for package: zabbix-server-mysql-3.0.3-1.el7.x86_64 --> Processing Dependency: libmysqlclient.so.18(libmysqlclient_18)(64bit) for package: php56w-mysql-5.6.23-1.w7.x86_64 --> Processing Dependency: libmysqlclient.so.18(libmysqlclient_18)(64bit) for package: zabbix-proxy-mysql-3.0.3-1.el7.x86_64 --> Processing Dependency: libmysqlclient.so.18(libmysqlclient_18)(64bit) for package: 2:postfix-2.10.1-6.el7.x86_64 --> Processing Dependency: libmysqlclient.so.18(libmysqlclient_18)(64bit) for package: zabbix-server-mysql-3.0.3-1.el7.x86_64 --> Running transaction check ---> Package php56w-mysql.x86_64 0:5.6.23-1.w7 will be erased --> Processing Dependency: php-mysql for package: zabbix-web-mysql-3.0.3-1.el7.noarch ---> Package postfix.x86_64 2:2.10.1-6.el7 will be erased ---> Package zabbix-proxy-mysql.x86_64 0:3.0.3-1.el7 will be erased ---> Package zabbix-server-mysql.x86_64 0:3.0.3-1.el7 will be erased --> Running transaction check ---> Package zabbix-web-mysql.noarch 0:3.0.3-1.el7 will be erased --> Processing Dependency: zabbix-web-database = 3.0.3-1.el7 for package: zabbix-web-3.0.3-1.el7.noarch --> Running transaction check ---> Package zabbix-web.noarch 0:3.0.3-1.el7 will be erased --> Finished Dependency Resolution slightly........ Complete! [root@i-orwnzsqu mysql]# [root@i-orwnzsqu mysql]# sudo yum autoremove Loaded plugins: fastestmirror No Packages marked for removal [root@i-orwnzsqu mysql]# [root@i-orwnzsqu mysql]# sudo yum clean all Loaded plugins: fastestmirror Cleaning repos: softinstll Cleaning up everything Maybe you want: rm -rf /var/cache/yum, to also free up space taken by orphaned data from disabled or removed repos Cleaning up list of fastest mirrors [root@i-orwnzsqu mysql]# #Check if uninstall is clean [root@i-orwnzsqu zysjswjw]# rpm -qa | grep mysql mysql-community-client-plugins-8.0.32-1.el7.x86_64 mysql-community-common-8.0.32-1.el7.x86_64 mysql57-community-release-el7-8.noarch #Continue to uninstall: [root@i-orwnzsqu zysjswjw]# sudo yum remove mysql mysql-common [root@i-orwnzsqu zysjswjw]# sudo yum remove mysql mysql-community-client-plugins-8.0.32-1.el7.x86_64 [root@i-orwnzsqu zysjswjw]# yum remove mysql mysql57-community-release-el7-8.noarch [root@i-orwnzsqu zysjswjw]# rpm -qa | grep mysql [root@i-orwnzsqu zysjswjw]#
3. Delete relevant data after uninstalling the installation package
Delete the relevant data files under the path in the red box
So far the uninstallation is complete, reinstall mysql5.7
3. mysql5.7 installation
1. Unzip the installation package
Decompress the compressed package: mysql-5.7.42-linux-glibc2.12-x86_64.tar
Decompress the compressed package: mysql-5.7.42-linux-glibc2.12-x86_64.tar.gz
Move and rename the decompressed directory to /usr/local/mysql
[root@i-orwnzsqu local]# mv /home/tdcxl/mysql-5.7.42-linux-glibc2.12-x86_64 /usr/local/mysql [root@i-orwnzsqu local]# cd /usr/local/mysql/ [root@i-orwnzsqu mysql]# ll total 284 drwxrwxr-x 2 tdcxl tdcxl 4096 Jul 3 12:00 bin drwxrwxr-x 2 tdcxl tdcxl 4096 Jul 3 12:00 docs drwxrwxr-x 3 tdcxl tdcxl 4096 Jul 3 12:00 include drwxrwxr-x 5 tdcxl tdcxl 4096 Jul 3 12:00 lib -rw-r--r-- 1 tdcxl tdcxl 255738 Mar 16 23:25 LICENSE drwxrwxr-x 4 tdcxl tdcxl 4096 Jul 3 12:00 man -rw-r--r-- 1 tdcxl tdcxl 566 Mar 16 23:25 README drwxrwxr-x 28 tdcxl tdcxl 4096 Jul 3 12:00 share drwxrwxr-x 2 tdcxl tdcxl 4096 Jul 3 12:00 support-files
2. Initialize the mysql database
[root@i-orwnzsqu mysql]# cd bin/
[root@i-orwnzsqu bin]# ./mysqld --user=tdcxl --initialize --datadir=/data/mysql
[root@i-orwnzsqu bin]#
#The root password generated by initialization is in log-error=/data/mysql/mysql.err
#Copy the startup file to the /etc/init.d/ directory
[root@i-orwnzsqu mysql]# cp -ar /usr/local/mysql/support-files/mysql.server /etc/init.d/mysqld
#Start the mysql service
[root@i-orwnzsqu mysql]# /etc/init.d/mysqld start
Starting MySQL. SUCCESS!
#Add autostart
[root@i-orwnzsqu mysql]# chkconfig --add mysql
[root@i-orwnzsqu mysql]#
[root@i-orwnzsqu mysql]# chkconfig --list
Note: This output shows SysV services only and does not include native
systemd services. SysV configuration data might be overridden by native
systemd configuration.
If you want to list systemd services use 'systemctl list-unit-files'.
To see services enabled on particular target use
'systemctl list-dependencies [target]'.
jexec 0:off 1:on 2:on 3:on 4:on 5:on 6:off
mysql 0:off 1:off 2:on 3:on 4:on 5:on 6:off
netconsole 0:off 1:off 2:off 3:off 4:off 5:off 6:off
network 0:off 1:off 2:off 3:off 4:off 5:off 6:off
[root@i-orwnzsqu mysql]#
#View the root password generated by default
3. Modify the root password
#Add environment variables to facilitate login
[root@i-orwnzsqu mysql]# mysql -uroot -p
-bash: mysql: command not found
[root@i-orwnzsqu mysql]# echo "export PATH=$PATH:/usr/local/mysql/bin" >> /etc/profile
[root@i-orwnzsqu mysql]# source /etc/profile
[root@i-orwnzsqu mysql]#
[root@i-orwnzsqu mysql]# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 5
Server version: 5.7.42
Copyright (c) 2000, 2023, Oracle and/or its affiliates.
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>
mysql> set password for root@localhost = password('12345678');
Query OK, 0 rows affected, 1 warning (0.00 sec)
mysql>
4. Install mysql5.7 client
Download address: https://downloads.mysql.com/archives/community/
If you are prompted to install dependent packages during the installation process, you can increase the nodeps parameter to reinstall, as follows: [root@i-orwnzsqu mysql]# rpm -ivh --nodeps MySQL-client-5.7.31-1.el6.x86_64.rpm
Attachment: Create database and user
mysql> create database tdcxltest; Query OK, 1 row affected (0.00 sec) #Build user: mysql> create user 'tdcxltest'@'%' identified by 'tdcxltest'; Query OK, 0 rows affected (0.02 sec) mysql> grant all privileges on tdcxltest.* to tdcxltest@'%'; Query OK, 0 rows affected (0.00 sec) mysql> flush privileges; Query OK, 0 rows affected (0.00 sec)
Test login:
