MySQL 5.6: the server quit without updating pid file

Introduction

MySQL is one of the most popular open-source relational database management systems (RDBMS). It is widely used in various applications ranging from small websites to large-scale enterprise solutions. However, users may encounter various issues while working with MySQL. One common issue is the error message "the server quit without updating pid file" which indicates a problem with the MySQL server startup. In this article, we will explore the possible causes of this error and provide some solutions to resolve it.

Understanding the Error

When starting the MySQL server, it updates a file called the "pid" file, which contains the process ID (PID) of the server. This file is used to identify and manage the running server process. The error message "the server quit without updating pid file" suggests that the server was unable to update this file during its startup process.

Possible Causes

There can be several reasons why the server fails to update the pid file. Let's take a look at some of the common causes:

  1. Insufficient Permissions: The server may not have the necessary permissions to update or create the pid file. This can occur if the server is running under a restricted user account or if the file system permissions are not properly set.

  2. Disk Space Issues: If the disk where the pid file is located does not have enough free space, the server may fail to update the file. This can happen if the disk is running out of space or if the file system has reached its quota limit.

  3. Incorrect Configuration: Incorrect configuration settings in the MySQL configuration file (my.cnf) can also cause this error. For example, if the pid-file option is set to an invalid file path or if the file itself is missing or inaccessible.

Resolving the Issue

Now, let's explore some possible solutions to resolve the "the server quit without updating pid file" error:

1. Check File Permissions

First, ensure that the user running the MySQL server has the necessary permissions to update the pid file. You can do this by checking the file permissions using the ls -l command in the terminal:

$ ls -l /path/to/pid/file

If the permissions are insufficient, you can change them using the chmod command:

$ chmod 755 /path/to/pid/file

2. Verify Disk Space

Check the available disk space on the partition where the pid file is located:

$ df -h

If the disk space is low, you may need to free up some space or allocate more space to the partition. Alternatively, you can change the location of the pid file to a partition with sufficient space by modifying the pid-file option in the my.cnf file.

3. Verify MySQL Configuration

Check the MySQL configuration file (my.cnf) to ensure that the pid-file option is correctly set. Open the file using a text editor:

$ sudo nano /etc/mysql/my.cnf

Locate the pid-file option and verify that the file path is correct. If the file does not exist, you can create it manually using the touch command:

$ sudo touch /path/to/pid/file

4. Restart MySQL Service

After making any necessary changes, restart the MySQL service to see if the error persists:

$ sudo service mysql restart

If the error still occurs, you may need to consult the MySQL logs for more detailed information. The log files are usually located in the MySQL data directory (/var/log/mysql or /var/lib/mysql).

Conclusion

The "the server quit without updating pid file" error can be caused by various factors such as insufficient permissions, disk space issues, or incorrect configuration settings. By following the solutions provided in this article, you should be able to resolve the issue and successfully start the MySQL server. Remember to always check the file permissions, disk space, and configuration settings before restarting the service.