CentOS 7にMySQLをインストールします。
さくらVPS 設定マニュアルを参考にMySQLのインストールを進めます。

環境

CentOS 7.7.1908
MySQL 5.7.x

rootで作業を進めます。

1. MariaDBの削除

CentOS7ではMariaDBがインストールされているため、MySQLと競合しないようにMariaDBとデータベースの削除が必要です。

# yum remove -y mariadb-libs
# rm -rf /var/lib/mysql

2. MSQLリポジトリを追加

# rpm -Uvh http://dev.mysql.com/get/mysql57-community-release-el7-11.noarch.rpm

3.MySQLのインストール

# yum -y install mysql-community-server

4.MySQLのバージョンを確認

# mysqld --version

5.MySQLの起動と自動起動の設定

MySQLを起動

# systemctl start mysqld.service

MySQLを自動起動に設定

# systemctl enable mysqld.service

6.MySQL初期パスワードを確認

# cat /var/log/mysqld.log | grep password
2019-10-17T08:26:34.542491Z 1 [Note] A temporary password is generated for root@localhost: eDKD&e.yJ1gE

初期パスワードはあとで変更する。

7. MySQLのセキュリティ設定

my.cnfにcharacter-set-serverとdefault_password_lifetimeの設定を追加します。

# vi /etc/my.cnf

# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/5.7/en/server-configuration-defaults.html

[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
#
# 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
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock

# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0

log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

# ここから追加
character-set-server = utf8
default_password_lifetime = 0

MySQLを再起度して設定を反映

# systemctl restart mysqld.service

8.MySQLへログイン

MySQLへrootでログインできることを確認する。

# mysql -u root -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.28 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>

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