MySQL Error Logs Not Found on Plesk Server (Ubuntu)

If you're using a Plesk server on Ubuntu, you may have encountered the issue of not being able to find the MySQL error logs. This can be frustrating, especially if you're not familiar with the Linux command line. But don't worry, in this article we'll walk you through the steps to locate the MySQL error logs on your Plesk server.

MySQL Error Logs: What Are They and Why Are They Important?

Before we dive into the steps to find the MySQL error logs, let's first understand what they are and why they're important. MySQL error logs are a record of all the errors that occur during the execution of MySQL. They can provide valuable information to help you troubleshoot issues with your MySQL server, such as failed login attempts, syntax errors, and more.

Step 1: Check the MySQL Configuration File

The first step to finding the MySQL error logs is to check the MySQL configuration file. The location of this file can vary depending on the version of MySQL you're using, but it's typically located in the /etc/mysql directory. The configuration file is named my.cnf or my.ini.

To view the contents of the MySQL configuration file, you can use the following command:

Once you've opened the configuration file, look for a line that starts with "log_error". This line specifies the location of the MySQL error logs. For example:

If you see this line, then you've found the location of the MySQL error logs. However, if you don't see this line, then the MySQL error logs may not be enabled. In this case, you can add the following line to the MySQL configuration file:

After adding this line, save the configuration file and restart the MySQL service using the following command:

Step 2: Check the System Logs

If the MySQL configuration file doesn't contain the "log_error" line, then you can check the system logs for MySQL error messages. On Ubuntu, the system logs are located in the /var/log directory. To view the system logs, you can use the following command:

Once you've opened the system logs, you can search for MySQL error messages using the following command:

This will display all the lines in the system logs that contain the words "mysql" and "error". Look for any error messages related to MySQL and make a note of the time they occurred.

Step 3: Check the MySQL General Log

If you're still having trouble finding the MySQL error logs, you can check the MySQL general log. The general log contains a record of all the queries that are executed on the MySQL server. While it's not specifically an error log, it can still provide valuable information to help you troubleshoot issues with your MySQL server.

To enable the MySQL general log, you can use the following command:

Once you've enabled the general log, you can view its contents using the following command:

Replace "[hostname]" with the name of your server. This will display the contents of the general log. Look for any queries that are causing errors and make a note of them.

Step 4: Check the MySQL Error Logs on the Filesystem

If none of the above steps have helped you find the MySQL error logs, then you can check the filesystem for any files that are named "error.log" or "mysql.err". These files may contain the MySQL error logs.

To view the contents of these files, you can use the following command:

Replace "mysql/error.log" with the name of the file you want to view. This will display the contents of the file. Look for any error messages related to MySQL and make a note of them.

Finding the MySQL error logs on a Plesk server on Ubuntu can be a daunting task, especially if you're not familiar with the Linux command line. However, by following the steps outlined in this article, you should be able to locate the MySQL error logs and troubleshoot any issues with your MySQL server.

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