when will the notification of RDS db-instance create subscription be generated?

Dear AWS Customer

From the notes, I understand that, you have subscribed to RDS db-instance "create" event. According to the subscription, it is expected that you shall be receiving a notification soon after the db instance was created; i.e. it comes into an Available state. However, you experienced a case wherein the end-point of db instance was unavailable when notification was received.

In an ideal condition, the event RDS-event-0005 will be triggered soon after the RDS instance is created and comes to an Available state.

Please allow me to share that, sometimes the event notifications might take up to five minutes to be delivered as documented in the below AWS article [+] :

[+] https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_Events.overview.html#USER_Events.overview.resources

In some cases, it may happen that although an event is triggered as the RDS gets created and comes into Available state, there may be a scenario when the RDS goes to unavailable/offline/rebooted during that period until the message arrives. In such cases, you may find the instance to be unavailable due to delayed delivery of message.

Furthermore, in case you encounter any such event, please reach out to us via a support case so that we can check your AWS resources and thoroughly investigate the root cause.

AWS RDS events are intended to provide a notification when the state of your DB instance changes. However, these events might not necessarily guarantee that the DB instance is fully operational and available for connections at the exact moment the event is sent.

The "create" event in RDS is triggered when the DB instance enters the "creating" state. This does not necessarily mean that the DB instance is fully operational. It just signifies that the creation process has begun.

After the DB instance is created, it transitions to the "backing-up" state while the initial backup is taken. Only after this backup completes does the DB instance transition to the "available" state and is ready to accept connections.

While the "create" event should be a good indicator that the process has begun, it's not a guarantee that the DB instance is ready. If you need to perform actions that require the DB instance to be available (like connecting to the database), you should wait for the "Available" state. You might want to set up a process that periodically checks the status of the DB instance until it becomes available.