MySQL official source does not boot after upgrading from 8.0.3 direct yum to 8.0.4

Server environment: centos7.4.14

Problem: MySQL does not start properly

View Logs

2018-02-23T02:10:08.371209Z 0 [System] [MY-010116] /usr/sbin/mysqld (mysqld 8.0.4-rc-log) starting as process 27702 ...2018-02-23T02:10:08.737713Z 1 [ERROR] [MY-011096] No data dictionary version number found.2018-02-23T02:10:08.737989Z 0 [ERROR] [MY-010020] Data Dictionary initialization failed.2018-02-23T02:10:08.738038Z 0 [ERROR] [MY-010119] Aborting

It was later discovered that the Caching_sha2_password authentication mechanism was enabled by default after the upgrade, and the previous data was not run directly.

You can only restore the original version, export the data from the original version, re-import it, or upgrade the import.

First, uninstall 8.0.4

Backing up data

mv /var/lib/{mysql,mysql.bak}chown -R mysql:mysql /var/lib/mysql.bakchmod 755 -R  /var/lib/mysql.bak

Direct Yum Offload

rpm -qa|grep ‘^mysql‘

Then will query out the 8.0.4 package all Yum Uninstall

Second, installation 8.0.3

Download 8.0.3 from official website

https://downloads.mysql.com/archives/community/

Download the packaged version of Mysql-8.0.3-0.1.rc.el7.x86_64.rpm-bundle.tar

Extract

tar -xvf mysql-8.0.3-0.1.rc.el7.x86_64.rpm-bundle.tar

Then install common, libs, client, server in turn

rpm -ivh mysql-community-common-8.0.3-0.1.rc.el7.x86_64.rpmrpm -ivh mysql-community-libs-8.0.3-0.1.rc.el7.x86_64.rpmrpm -ivh mysql-community-client-8.0.3-0.1.rc.el7.x86_64.rpmrpm -ivh mysql-community-server-8.0.3-0.1.rc.el7.x86_64.rpm

Start MySQL

systemctl start msyqld.service

At this point,/var/lib/a new MySQL folder is regenerated.

Third, data export

Modify /etc/my.cnf point to old data

[mysqld]innodb_force_recovery = 6datadir=/var/lib/mysql.bak

Forcing InnoDB Recovery offers 6 levels of repair mode
Innodb_force_recovery Reference: http://blog.csdn.net/weitao_11/article/details/55050200

Full-Library Export:
Mysqldump-uroot-p--all-databases >/home/sqlfile.sql

Iv. Data Recovery

Modify the /etc/my.cnf data path, remove the repair mode, repair mode is not writable

[mysqld]datadir=/var/lib/mysql

View temporary password

[[email protected]]# cat /var/log/mysqld.log|grep password2018-02-23T08:06:36.785974Z 5 [Note] A temporary password is generated for [email protected]: Leyk2qO_75ER

Log in to MySQL with a temporary password, change the password

Discard upgrade, import data directly

mysql -uroot -pmysql>GRANT ALL PRIVILEGES ON *.* TO ‘root‘@‘localhost‘ IDENTIFIED BY ‘[email protected]‘ WITH GRANT OPTION;mysql>flush privileges;mysql>source /home/sqlfile.sql;

After reboot, everything is OK. Be sure to back up before you upgrade, and always back up.

MySQL official source does not boot after upgrading from 8.0.3 direct yum to 8.0.4