Hello and welcome to this short lecture which will introduce you to the object level logging capabilities with your S3 buckets.

This feature is actually more closely related to the AWS CloudTrail service than S3 in a way, as it’s AWS CloudTrail that performs logging activities against Amazon S3 data events. These data events are specific API calls used in S3, such as GetObject, DeleteObject, and PutObject.

So what is CloudTrail? CloudTrail is a service that has a primary function to record and track all AWS API requests made. These API calls can be programmatic requests initiated from a user using an SDK, the AWS command-line interface, from within the AWS management console or even from a request made by another AWS service.

When an API request is initiated, AWS CloudTrail captures the request as an event and records this event within a log file which is then stored on S3. Each API call represents a new event within the log file. CloudTrail also records and associates other identifying metadata with all the events. For example, the identity of the caller, the timestamp of when the request was initiated and the source IP address.

We have a detailed course on AWS CloudTrail which an be found here which will provide a deep insight into the service and its full capabilities.

Capturing S3 data events can be configured in 2 ways: Firstly, if you want to capture data events for all or some of your S3 buckets, then you can configure this from within one of your Trails using the AWS CloudTrail console itself as shown here. Secondly, if it’s not already enabled via AWS CloudTrail for your bucket you can configure it at the bucket level using the Properties tab. Selecting the Object-level logging tile will present you with options to configure it.

As you can see, due to its integration with AWS CloudTrail you will be asked to select an existing trail from the same region to capture your S3 data events for this bucket. In this example, I have used my ‘Trail_Demo’ trail. You must also select which type of events you would like to capture, either just Read events or Write events, or both. Once you have made your selection, simply select Create and Object-level logging will be enabled and AWS CloudTrail will capture any S3 Data events associated with this bucket.

For more information on where your CloudTrail logs are stored and accessed, and how to interpret your CloudTrail logs, please see our existing course here.