“MySQL server has gone away” Error on Joomla

One of our regular clients was seeing the following error when trying to view the VirtueMart orders in the backend of his Joomla 3.3.6 website:

Error displaying the error page: Could not connect to MySQL.: MySQL server has gone away SQL=SELECT SQL_CALC_FOUND_ROWS o.*, CONCAT_WS(‘ ‘,u.first_name,u.middle_name,u.last_name) AS order_name ,u.email as order_email,pm.payment_name AS payment_method FROM #__virtuemart_orders as o LEFT JOIN #__virtuemart_order_userinfos as u ON u.virtuemart_order_id = o.virtuemart_order_id AND u.address_type=”BT” LEFT JOIN #__virtuemart_paymentmethods_en_gb as pm ON o.virtuemart_paymentmethod_id = pm.virtuemart_paymentmethod_id ORDER BY created_on DESC LIMIT 0, 100

Obviously, the above SQL query was causing the MySQL server to go away – but what does going away mean in this context? It typically means that the server timed out while processing the above query (which takes a lot of time).

Hmmm! Easily fixable, we thought. We ssh’d to the server and we edited the my.cnf file (this file contains all of MySQL‘s settings) located under the /etc folder the following way:

  • We opened the file in vi:

    vi /etc/my.cnf

  • We changed the value of max_allowed_packet to 256M.

  • We closed the file and then we restarted MySQL by issuing the following command (this step is necessary so that MySQL starts with the new settings – note that on some Linux installations, the command to restart MySQL is different):

    /etc/init.d/mysql restart

  • We checked the problematic page (the one displaying the VirtueMart orders), and it still had the same problem.

No problem! We opened again the file my.cnf and we added the following lines:


We restarted MySQL and tried again, but still, the same problem.

We started to feel a bit of pressure – but we thought – maybe we will be able to find something in MySQL‘s error log. So we checked that error log, and we noticed that there was a problem with the innodb_index_stat table (this is a core MySQL table and it is used for InnoDB tables). We checked that table through phpMyAdmin (it is located in the core mysql database), and we got the following error: table ‘mysql.innodb_index_stats’ doesn’t exist

Huh? At this point, we were no longer surprised by the error that our client was getting, but we were astonished that the rest of the website was working since a core MySQL table, the ‘mysql.innodb_index_stats’ table, was corrupt.

We tried everything – we tried every imaginable method to repair the table – but none worked. Eventually what we did was that we created a backup of the database and then re-installed MySQL, and finally re-imported the database. Everything worked as normal once we did that!

But what caused this problem in the first place?

We’re not certain – we suspect a server crash that happened recently caused this problem. But, in all fairness, the actual reason might not be it. The good news, however, is that we got this problem solved!

If you’re seeing the “MySQL server has gone away” error on your Joomla website, then try the above solutions in sequence. If none of them worked, then your best bet would be to re-install MySQL as quite possibly you have a corrupt instance of the DB server. If you need help fixing this problem then please contact us. Our fees are super affordable, our work is quick and very professional, and we are the friendliest developers on planet Earth.

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