How can I get objects in a S3 bucket?

Amazon S3: What are the use cases for getting SNS notifications for lost Reduced Redundancy Storage objects?

• Amazon S3 users are allowed to set up SNS notifications when a Reduced Redundancy Storage object is lost. Why would someone find this useful? What are the use cases? Enabling notifications causes a message to be published to an Amazon Simple Notification Service (SNS) Topic when Amazon S3 detects that a Reduced Redundancy Storage object stored in this bucket is lost.

• Answer:

  It's used for awareness and corrective action. For example: 1) I'm storing a pre-computed thumbnail, and it disappears. I might have a process programatically recompute and reupload it very quickly before users are impacted. 2) It might help me debug issues while on-call. For example, if I get paged, and then I see error rates spike, it would be useful to check SNS and see if there are any dead objects. 3)  In theory you could also use it to ensure overall integrity of your data set. For example, if you're storing the results of intermediate scientific computation in S3 that you can't easily reproduce, it would be useful - but this is probably a much rarer use-case in the real world.