How do I Check and Set the `max_allowed_packet` Variable in MySQL?

Checking and Setting the max_allowed_packet MySQL Variable

MySQL stores the max_allowed_packet variable within its configuration settings. To check its current value, you can execute the following query:

SHOW VARIABLES LIKE 'max_allowed_packet';

Shared hosting environments may restrict user-initiated changes to server settings. However, you can attempt to modify the variable using the following query (although it may not be feasible on shared hosting):

SET GLOBAL max_allowed_packet=16777216;

Note that MySQL reads the max_allowed_packet variable from the [mysqld] section of the MySQL configuration file (my.cnf on Linux). Ensure that the variable is defined in this section for it to take effect.

In previous versions of MySQL, the [mysqld_safe] section was used to set server variables. However, since MySQL version 5.5, the [mysqld] section has become the preferred method for managing variables like max_allowed_packet.

Therefore, if you are using MySQL version 5.5 or higher, you should set the max_allowed_packet variable as follows:

[mysqld]
max_allowed_packet=16M

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