MySQL query failed: MySQL server has gone away

[AdrianB]

When I log-in to Plesk Control Panel and try to access the server section I get the following error:

ERROR: PleskMainDBException
MySQL query failed: Lost connection to MySQL server during query

Additionally, an exception has occurred while trying to report this error: PleskMainDBException
MySQL query failed: MySQL server has gone away

0: /opt/psa/admin/plib/common_func.php3:250
db_query(string 'SELECT `id`, `ord`, `uri`, `parent_id`, `enabled`, `type`, `title`, `description` FROM `DashboardPresetConfig` WHERE `preset_id`="1" ORDER BY `ord` DESC')
1: /opt/psa/admin/plib/dashboard/DashboardPreset.php:160
DashboardPreset->fetchConfig()
2: /opt/psa/admin/plib/dashboard/DashboardPreset.php:296
DashboardPreset->getConfig()
3: /opt/psa/admin/plib/dashboard/DashboardPreset.php:103
DashboardPreset->getElementByURI(string '/plesk/dashboard/#shortcuts')
4: /opt/psa/admin/plib/dashboard/Dashboard.php:152
Dashboard::getShortcutParent(object of type DashboardPreset, object of type plesk__server)
5: /opt/psa/admin/plib/class.Form.php:244
Form->assign()
6: /opt/psa/admin/plib/class.ServerForm.php:172
ServerForm->assign(object of type ComponentsChecker)
7: /opt/psa/admin/htdocs/server/server.php3:115

This first happened after the first server restart in 145 days, then, overnight it seemed to have resolved by itself. But today the error appeared again. If I do a mysqlcheck on the psa database I get: mysqlcheck: Got error: 2002: Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (111) when selecting the database

I've checked, the socket exists. The other databases work with no problem.

 

[Maa]

There are too much reasons for this.
Maybe you have modified /etc/my.cnf

Also you can check MySQL error log:

# grep error /etc/my.cnf
log-error=/var/log/mysqld.log

Here are some troubleshooting steps from mysql site:

http://dev.mysql.com/doc/refman/5.0/en/gone-away.html

 

[lvalics]

see the timeout ... that could be the issue in my.cnf