How to customize MySQL/MariaDB variables on a Plesk server?

Kuzma Ivanov

Updated February 01, 2026 01:47

Plesk for Windows kb: how-to Plesk for Linux ABT: Group A

Applicable to:

Plesk for Linux
Plesk for Windows

Question

How to customize MySQL variables (e.g. max_allowed_packet, read_buffer_size connect_timeout or wait_timeout) on a Plesk server?

Answer

Note: Custom values must not exceed the limits defined by MySQL. For example, the highest value for max_allowed_packet is 1073741824 bytes (1024M) for wait_timeout - 31536000 seconds.

For Plesk on Linux

Connect to your Plesk server via SSH.
Open the my.cnf file in a text editor. In this example, we are using vi editor:
- on CentOS/RHEL-based distributions:
  
  # vi /etc/my.cnf
- on Debian/Ubuntu-based distributions:
  
  # vi /etc/mysql/my.cnf
Add your custom variables under the [mysqld] section. If the variable is also applicable to [client], [mysql] and [mysqldump] sections, add it there too.

In this example, we are adding max_allowed_packet and wait_timeout directives:

CONFIG_TEXT: [mysqld]
wait_timeout = 31536000
connect_timeout = 10
max_allowed_packet = 1024M
...
[mysqldump]
max_allowed_packet = 1024M
Save the changes and close the file.
Restart the MySQL/MariaDB service:

# systemctl restart mysql || systemctl restart mariadb

For Plesk on Windows Server

Connect to your Plesk server via RDP.
Open the file %plesk_dir%Databases\MySQL\my.ini in a text editor.
Add your custom variables under the [mysqld] section. If the variable is also applicable to [client] and [mysqldump] sections, add it there too.

In this example, we are adding max_allowed_packet and wait_timeout:

CONFIG_TEXT: [mysqld]
wait_timeout = 31536000
connect_timeout = 10
max_allowed_packet = 1024M
...
[mysqldump]
max_allowed_packet = 1024M
Save the changes and close the file.
Restart the MySQL/MariaDB service via Windows Services or Plesk Services Monitor.