connect_timeout – the number of seconds that the mysql server waits for the connection package before terminating the connection.
Connect to MySQL and see the current value:
mysql -u USER -p show variables like "connect_timeout"; quit;
The value of connect_timeout can be specified in the file /etc/mysql/my.cnf, for example:
[mysqld] connect_timeout=10
In real time, you can change by executing the SQL query (after restarting MySQL it will be reset to the standard or specified in the configuration file):
SET GLOBAL connect_timeout=10;
The standard value is 10, the minimum value is 2, the maximum is 31536000.