Unable to acquire JDBC Connection

[anshul_sehgal]

We were getting below exceptions in logs for few days 

- [security.denormalisedpermissions.impl.DenormalisedPermissionStateManagerImpl] reloadServiceState reloadServiceState failed: Could not open Hibernate Session for transaction; nested exception is net.sf.hibernate.exception.JDBCConnectionException: Unable to acquire JDBC Connection org.springframework.transaction.CannotCreateTransactionException: Could not open Hibernate Session for transaction; nested exception is net.sf.hibernate.exception.JDBCConnectionException: Unable to acquire JDBC Connection at org.springframework.orm.hibernate.HibernateTransactionManager.doBegin(HibernateTransactionManager.jav

- runJob Scheduled job confluence.extra.webdav:contentJobQueueExecutor#contentJobQueueExecutorTrigger jobToBeExecuted failed to run org.springframework.transaction.CannotCreateTransactionException: Could not open Hibernate Session for transaction; nested exception is net.sf.hibernate.exception.JDBCConnectionException: Unable to acquire JDBC Connection at org.springframework.orm.hibernate.HibernateTransactionManager.doBegin(HibernateTransactionManager.java:476) ... 24 lines omitted ... Caused by: net.sf.hibernate.exception.JDBCConnectionException: Unable to acquire JDBC Connection

- onCronEvent Unable to process records: Could not open Hibernate Session for transaction; nested exception is net.sf.hibernate.exception.JDBCConnectionException: Unable to acquire JDBC Connection org.springframework.transaction.CannotCreateTransactionException: Could not open Hibernate Session for transaction; nested exception is net.sf.hibernate.exception.JDBCConnectionException: Unable to acquire JDBC Connection at org.springframework.orm.hibernate.HibernateTransactionManager.doBegin(HibernateTransactionManager.java:476) ... 27 lines omitted ... at java.base/java.lang.Thread.run(Unknown Source) Caused by: net.sf.hibernate.exception.JDBCConnectionException: Unable to acquire JDBC Connection

And after reboot of the server all exceptions have gone away. What can be the reason of these errors going away suddenly. Any pointers will be helpful

[Shawn Doyle - ReleaseTEAM · Accepted solution]

Try going thru this post.

https://confluence.atlassian.com/confkb/unable-to-start-due-to-net-sf-hibernate-exception-genericjdbcexception-cannot-open-connection-128843899.html

However, if Confluence is working and you have just noticed these exceptions in the log, it's likely that Confluence was having issues connecting to the database resolved itself.

[anshul_sehgal]

Thanks @Shawn Doyle - ReleaseTEAM , Our errors existed for almost 10 days and when we reinstalled confluence on new host, it got resolved, so not able to figure out what got changed during that time which resolved the issue.

Note : There are no database changes done.