Docker上のmysqlのrootのパスワードが不明でハマった件

調査内容

Dockerというか普通にmysqlのトラブルシューティングで探すと、「–initialize-insecure」の実施が必要。

https://qiita.com/park-jh/items/1e118580ae1deab70f99

logを確認すると、「–initialize-insecure」を実施しろと。

https://kitsune.blog/mysql-login

[root@7aa3fe2e9efc log]# grep password /var/log/mysql/mysqld.log
2021-01-11T19:01:10.555127Z 6 [Warning] [MY-010453] [Server] root@localhost is created with an empty password ! Please consider switching off the --initialize-insecure option.

実施、再起動

[root@7aa3fe2e9efc log]# mysqld --initialize-insecure --user=mysql

[root@7aa3fe2e9efc log]# systemctl start mysqld

パスワードなしで入れた！

[root@7aa3fe2e9efc log]# mysql -u root
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 8
Server version: 8.0.21 Source distribution

Copyright (c) 2000, 2020, 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>

mysql root のパスワード設定

https://webkaru.net/mysql/mysql-root-password/

$mysqladmin -u root password 'PASSWORD'