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Increase Max Allowed Packet and Lock Wait Timeout Settings in MySQL Configuration

Background

According to MySQL discussion forums, a max_allowed_packet value that is too low (such as 4M) can cause connection issues with MySQL, which can look like the following in Variphy Logs:

ERROR … com.mysql.jdbc.CommunicationsException: Communications link failure due to underlying exception: 

** BEGIN NESTED EXCEPTION ** 

java.net.SocketException
MESSAGE: socket closed


STACKTRACE:
java.net.SocketException: socket closed

Resolution

Within the [mysqld] section in my.cnf (my.ini on Windows):

max_allowed_packet=100M

innodb_lock_wait_timeout=120

In running config (via MySQL cmd line or workbench):

SET GLOBAL max_allowed_packet=104857600;

SET GLOBAL innodb_lock_wait_timeout = 120; 

Updated on March 30, 2020

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