Issue Summary

An instance's mail handler may become unavailable during server downtime or a maintenance window. While queueing does exist, the mail server will attempt re-delivery without knowledge of whether the mail handler is available to receive the email.

In this scenario, a bounced email will be returned to the original mail server. On automated systems, a high volume of bounces may cause the origin mail server to block the email address preventing further emails even when the instance is up and running.

Steps to Reproduce

The behavior can be reproduced when an instance is down or in maintenance mode.

Expected Results

• It would be beneficial if the queue had a defined re-delivery schedule before deciding to bounce the email.
• Additionally the instance's mail handler could send a notification that it is back up and running to alert the queue to attempt re-delivery

Actual Results

As described above, currently there will be an attempted re-delivery without the mail server [queue] being aware whether the instance mail handler is functional or not. This can result in a failed delivery again and an email bounce back to the mail origin server.

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available