Unable to acquire JDBC Connection when using mysql db for camunda

Camunda 7 Topics Discussion & Questions
1

Hi Team,
I am using azure mysql database for my camunda instance which is hosted on azure. Intermittently I am getting “Unable to acquire JDBC Connection” after I submit around 40-50 request to start a workflow. Error message as below. However, it works fine after sometime.
ENGINE-REST-HTTP500 org.springframework.transaction.CannotCreateTransactionException: Could not open JPA EntityManager for transaction; nested exception is org.hibernate.exception.JDBCConnectionException: Unable to acquire JDBC Connection
Did anyone face similar issue?Is there any fix for this?
Thanks.

2

Hi @rashmiagrl Welcome to the forum :tada:

Consider these points to solve this issue:

  • Configure HikariCP or Tomcat-jdbc connection pool in the process application or jndi data source
  • Hold maximum active connections at least >=10
3

Thanks for the suggestion. I am currently using HikariCP connection pool and given max pool size as 20. But still getting the same error.

4

Hi @rashmiagrl,

I suspect that this issue is not related to the Camunda Engine as the engine didn’t use hibernate.

Maybe it’s thrown in custom code? Have a look at the complete stack trace.

Hope this helps, Ingo

5

@rashmiagrl Which transaction manager are you using?

6