After JIRA upgrade to 5.1.3 from 4.4.1, we don't get any notifications from JIRA.
When I went through mail queue, there was more than 1000 mails. I had to flush the queue to get mails delivered.
Is this a bug in 5.1.3 ? or should I make any changes in config ? Now, I am flushing mail queue once in an hour.