Spring Boot library for Quartz does not work correctly if you start up two instances of service in parallel. Each one of the services starts the execution of the same jobs while the expected behavior is one of the instances is elected to execute the jobs and the other ones waiting in the background, and in the case of failure of the first service, another one is elected.
Springs’ @Scheduled annotation is a very convenient and easy way of scheduling tasks for several reasons. But, if you have a clustered environment and you must run any job just from one node, that does not hold true. You realize that all scheduled jobs will start executing almost at the same time. This may cause problems ranging from unnecessary calls to data inconsistency.