MySQL Default Password: How to Find, Change, and Reset It (Linux & Windows Guide)

1. Introduction

MySQL is a widely used and popular database management system across many systems and environments. As part of the initial setup, confirming and properly managing the default password is extremely important. If the initial password is not handled correctly, it may lead to security risks or access issues.

This article explains how to check the MySQL default password, how to change it, and how to resolve issues if problems occur—all in a way that beginners can easily understand.

2. What Is the MySQL Default Password?

Overview of the Default Password

When MySQL is installed for the first time, an initial password is set for the database administrator user (usually “root”). The behavior of this password varies depending on the MySQL version.

Differences by Version

• MySQL 5.7 and later: A temporary password is automatically generated during installation and written to the log file.
• Earlier versions: It is common for MySQL to be installed without a password (empty password).

Why the Default Password Is Important

If the default password is not properly managed, the risk of unauthorized access increases. After installation, it is strongly recommended to confirm the password and change it if necessary.

3. How to Check the Default Password

For Linux Environments

If you installed MySQL on a Linux environment, you can check the default password using the following steps.

1. Log in and open the terminal.
2. Run the following command to check the log file.

   sudo grep 'temporary password' /var/log/mysqld.log

3. In the output, look for the line containing “temporary password.” The default password will be displayed after it.

Example:

2025-01-22T10:22:33.123456Z 1 [Note] A temporary password is generated for root@localhost: Abc123!@#

For Windows Environments

In a Windows environment, you need to manually check the mysqld.log file.

1. Open the MySQL installation folder (usually C:\ProgramData\MySQL\MySQL Server X.X).
2. Locate the mysqld.log file and open it with a text editor.
3. Search for “temporary password,” similar to the Linux method.

Important Notes

• If the default password does not appear in the log file, refer to the troubleshooting section below.

4. How to Change the Default Password

Using MySQL with its default configuration increases security risks. Therefore, it is recommended to change the default password immediately after installation. Below are the detailed steps for changing it.

Changing the Password Using the mysql_secure_installation Command

mysql_secure_installation is a command-line tool that helps configure MySQL’s initial security settings. Using this tool allows you to enhance security, including changing the default password, in one process.

1. Open the terminal or command prompt and run the following command.

   sudo mysql_secure_installation

2. You will be prompted to enter the default password. Enter the password confirmed during installation.
3. You will see an option to configure the password policy. Select an appropriate strength (strong passwords are recommended).
4. Enter a new password, then re-enter it for confirmation.
5. Follow the prompts to configure additional security settings (such as removing anonymous users and disabling remote root login).

Changing the Password Manually

You can also change the password directly using SQL from the command line.

1. Log in to MySQL.

   mysql -u root -p

2. Run the SQL command to change the password.

   ALTER USER 'root'@'localhost' IDENTIFIED BY 'NewStrongPassword';

※ Replace NewStrongPassword with a secure password.

3. Apply the changes by running:

   FLUSH PRIVILEGES;

4. Exit MySQL.

   exit

Setting Password Policy and Strength

In some cases, MySQL enables password policies by default. This policy prevents the use of weak passwords to enhance security.

• To check the current policy, run:

   SHOW VARIABLES LIKE 'validate_password%';

• To relax the policy, modify the following setting:

   SET GLOBAL validate_password.policy=LOW;

Important Notes

• After changing the password, you may be unable to access MySQL. In that case, check the configuration files and connection settings.
• Choosing a strong password significantly reduces the risk of unauthorized access.

5. What to Do If You Cannot Confirm the Default Password

If you cannot confirm the MySQL default password, there may be an issue with the log file configuration or the procedure. This section explains the possible causes and specific solutions.

If the Default Password Is Not Output in the Log

In MySQL 5.7 and later, the default password is written to the log file. However, depending on the configuration or environment, it may not be recorded.

Points to Check

1. Log File Location:
   The default path of the MySQL log file is as follows.

• Linux: /var/log/mysqld.log
• Windows: C:\ProgramData\MySQL\MySQL Server X.X\mysqld.log Check the configuration file (my.cnf or my.ini) to ensure the log output destination has not been changed.

2. Log Level Settings:
   If the MySQL log level is not configured correctly, the default password may not be recorded. Edit the my.cnf file and add or verify the following settings.

   [mysqld]
   log_error=/var/log/mysqld.log

How to Reset the Password If It Is Unknown

If the password does not appear in the log or if you have lost the default password, you can reset it using the following procedure.

Steps:

1. Start MySQL in Safe Mode:
   Safe mode allows you to access MySQL without authentication.

   sudo systemctl stop mysqld
   sudo mysqld_safe --skip-grant-tables &

2. Log in to MySQL:
   Access MySQL without authentication.

   mysql -u root

3. Reset the Password:
   Run the SQL command to reset the password.

   ALTER USER 'root'@'localhost' IDENTIFIED BY 'NewStrongPassword';

※ Replace NewStrongPassword with a secure password.

4. Apply the Changes:

   FLUSH PRIVILEGES;

5. Restart MySQL:
   Exit safe mode and restart MySQL in normal mode.

   sudo systemctl restart mysqld

If the Issue Is Not Resolved

If the issue is not resolved using the above steps, consider the following options.

• Reinstall MySQL:
  If the database has not been used yet, you may reinstall MySQL to return it to its initial state.
• Consult Official Documentation or Support:
  If a specific error message is displayed, refer to the official MySQL documentation or forums.

6. FAQ

Here are frequently asked questions and answers regarding the MySQL default password. Refer to this section to quickly resolve doubts or issues.

Q1: What should I do if I forgot the default password?

If you forgot the default password, you can reset it using the following steps.

1. Stop MySQL.

   sudo systemctl stop mysqld

2. Start MySQL in safe mode.

   sudo mysqld_safe --skip-grant-tables &

3. Log in to MySQL and set a new password.

   ALTER USER 'root'@'localhost' IDENTIFIED BY 'NewStrongPassword';
   FLUSH PRIVILEGES;

4. Restart MySQL to return to normal mode.

   sudo systemctl restart mysqld

Q2: How can I verify the password after changing it?

To confirm that the new password works correctly, follow these steps.

1. Log in to MySQL.

   mysql -u root -p

2. If you can log in successfully after entering the password, the configuration is correct.
3. For confirmation, run the following SQL command to check authentication information.

   SELECT user, host, authentication_string FROM mysql.user;

Q3: How do I change the password policy?

MySQL enforces a password policy by default, but you can relax the requirements if needed.

1. Check the current password policy.

   SHOW VARIABLES LIKE 'validate_password%';

2. To change the policy, run:

   SET GLOBAL validate_password.policy = LOW;

3. If necessary, you can also modify the minimum length and complexity settings.

   SET GLOBAL validate_password.length = 8;

Q4: I cannot find the log file that contains the default password. What should I do?

If you cannot find the log file, try the following steps.

1. Check the configuration file (my.cnf or my.ini) and identify the path of log_error.
2. If the configuration is incorrect, explicitly set the log file output location.

   [mysqld]
   log_error=/var/log/mysqld.log

3. Restart MySQL to apply the changes.

Q5: What happens if MySQL does not have a default password?

Depending on the version, MySQL may be installed with no password (empty password). In that case, set a new password using the following steps.

1. Log in to MySQL.

   mysql -u root

2. Set a password.

   ALTER USER 'root'@'localhost' IDENTIFIED BY 'NewStrongPassword';

7. Conclusion

The MySQL default password is a critical element in securely managing your database. In this article, we covered how to check the default password, how to change it, and how to troubleshoot related issues. Below is a summary of the key points.

Key Takeaways

• Importance of the Default Password: For security reasons, it is strongly recommended to confirm and change the password immediately after installation.
• How to Check It: You can easily verify it by reviewing the log file (mysqld.log).
• How to Change It: The default password can be changed using the mysql_secure_installation tool or by executing SQL commands directly.
• Troubleshooting: If you cannot confirm the default password, you can reset it by checking log settings or using safe mode.
• FAQ: Common password-related questions were addressed to help readers resolve issues quickly.

Message to Readers

When using MySQL, properly managing the default password is essential to minimize security risks. In addition, regularly changing your password and following security policies will help ensure safe and efficient database operations.

Next Steps

Use this article as a reference to review your MySQL initial configuration and implement the necessary security measures. If issues arise, consult the troubleshooting steps and FAQ section to guide your response.