Возможно, рассмотрите возможность использования более короткого значения maxLifetime - весенняя загрузка пула соединений ⇐ JAVA

[Anonymous]

После запуска приложения SpringBoot через несколько минут после запуска сервера появилось исключение. Не использовал какую-либо внешнюю конфигурацию HikariPool, Spring Boot использует HikariPool по умолчанию
Это ошибка, которую я получаю в консоли:

2020-02-20 03:16:23 - HikariPool-4 - Failed to validate connection
com.mysql.cj.jdbc.ConnectionImpl@4c4180c8 (No operations allowed after connection closed.).
Possibly consider using a shorter maxLifetime value.
2020-02-20 03:16:28 - HikariPool-4 - Failed to validate connection
com.mysql.cj.jdbc.ConnectionImpl@679c2f50 (No operations allowed after connection closed.).
Possibly consider using a shorter maxLifetime value.
2020-02-20 03:16:33 - HikariPool-4 - Failed to validate connection
com.mysql.cj.jdbc.ConnectionImpl@16083061 (No operations allowed after connection closed.).
Possibly consider using a shorter maxLifetime value.
2020-02-20 03:16:38 - HikariPool-4 - Failed to validate connection
com.mysql.cj.jdbc.ConnectionImpl@4fcaf421 (No operations allowed after connection closed.).
Possibly consider using a shorter maxLifetime value.
2020-02-20 03:16:43 - HikariPool-4 - Failed to validate connection
com.mysql.cj.jdbc.ConnectionImpl@33df5d54 (No operations allowed after connection closed.).
Possibly consider using a shorter maxLifetime value.
2020-02-20 03:16:48 - HikariPool-4 - Failed to validate connection
com.mysql.cj.jdbc.ConnectionImpl@373d288c (No operations allowed after connection closed.).
Possibly consider using a shorter maxLifetime value.
2020-02-20 03:16:48 - SQL Error: 0, SQLState: 08003
2020-02-20 03:16:48 - HikariPool-4 - Connection is not available, request timed out after
30156ms.
2020-02-20 03:16:48 - No operations allowed after connection closed.
2020-02-20 03:16:48 - Servlet.service() for servlet [dispatcherServlet] in context with path
[] threw exception [Request processing failed; nested exception is
org.springframework.dao.DataAccessResourceFailureException: Unable to acquire JDBC
Connection; nested exception is org.hibernate.exception.JDBCConnectionException: Unable to
acquire JDBC Connection] with root cause


Подробнее здесь: https://stackoverflow.com/questions/603 ... n-pool-spr