CentOS is one of the common Linux operating systems. It is an open source, stable and efficient operating system. As a developer, we often need to install MySQL database on CentOS system. This article will introduce you to the detailed steps on how to successfully install a MySQL database on a CentOS system.
1. Preparations before installing the MySQL database
1. First, we need to install the wget command on the CentOS system. The command is as follows:
sudo yum -y install wget
2. Install MySQL Before installing the database, it is recommended that we upgrade the system first to ensure that the system has the latest security patches and software packages. The command is as follows:
sudo yum update -y
3. When installing a MySQL instance, you need to use the GCC compiler. You can use the following Method to install:
sudo yum install -y gcc
2. Install MySQL database through Yum
1. First we need to import the official software source of MySQL, use the following command to import:
wget https://dev.mysql.com/get/mysql80-community-release-el7-3.noarch.rpm sudo rpm -ivh mysql80-community-release-el7-3.noarch.rpm
2 . After importing the MySQL official software source, we can use the Yum command to directly install the MySQL database. The command is as follows:
sudo yum install -y mysql-community-server
In this step, Yum will grab the latest version of the MySQL database and install the related software packages. During this process, the system will automatically create a user and a system unit file for MySQL. After the installation is complete, the MySQL service will start automatically.
3. Configuration after MySQL installation
1. Check the status of the MySQL service to ensure whether the installation is successful:
sudo systemctl status mysqld
If the MySQL database is running normally, the command returns the following results :
● mysqld.service - MySQL Server Loaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset: disabled) Active: active (running) since Fri 2021-06-11 12:34:45 CST; 9min ago
2. Obtain the initial password of MySQL. During the first installation, MySQL will give a random password for the first login to the MySQL server. You can use the following command to obtain the initial password:
sudo grep 'temporary password' /var/log/mysqld.log | awk '{print $NF}'
3. Use the obtained MySQL password to log in:
mysql -u root -p
4. After entering the MySQL server, change the MySQL password. The command is as follows:
ALTER USER 'root'@'localhost' IDENTIFIED BY 'new_password';
Replace new_password with the password you need to change.
So far, we have successfully installed the MySQL database on the CentOS system. If you need to connect to a MySQL database from a remote host, some additional setup is required.
Summary
MySQL database is a powerful relational database management system that can be used to store and process various types of data. In this article, we introduce to you the whole process of installing MySQL database on CentOS system. Hope this article is helpful to you.
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