AWS CloudTrail
User Guide (Version 1.0)

CloudTrail Concepts

This section summarizes basic concepts related to CloudTrail.

What Are CloudTrail Events?

An event in CloudTrail is the record of an activity in an AWS account. This activity can be an action taken by a user, role, or service that is monitorable by CloudTrail. CloudTrail events provide a history of both API and non-API account activity made through the AWS Management Console, AWS SDKs, command line tools, and other AWS services. There are two types of loggable events in CloudTrail: management events and data events. By default, trails log management events, but do not log data events.

Both management events and data events use the same CloudTrail JSON log format. They are easily distinguished by the value in the managementEvent field.


CloudTrail does not log all AWS services. Additionally, some AWS services do not enable logging of all APIs and events. Even if you configure logging all management and data events in a trail, you will not create a log with all possible AWS events. For more information about unsupported services, see CloudTrail Unsupported Services. For specific details about what APIs are logged for a specific service, see that service's documentation in CloudTrail Topics by AWS Service.

What Are Management Events?

Management events provide insight into management operations that are performed on resources in your AWS account. These are also known as control plane operations. Example management events include:

  • Configuring security (for example, IAM AttachRolePolicy API operations)

  • Registering devices (for example, Amazon EC2 CreateDefaultVpc API operations)

  • Configuring rules for routing data (for example, Amazon EC2 CreateSubnet API operations)

  • Setting up logging (for example, AWS CloudTrail CreateTrail API operations)

Management events can also include non-API events that occur in your account. For example, when a user logs in to your account, CloudTrail logs the ConsoleLogin event. For more information, see Non-API Events Captured by CloudTrail. For a list of supported management events that CloudTrail logs for AWS services, see CloudTrail Topics by AWS Service.

What Are Data Events?

Data events provide insight into the resource operations performed on or within a resource. These are also known as data plane operations. Data events are often high-volume activities. Example data events include:

  • Amazon S3 object-level API activity (for example, GetObject, DeleteObject, and PutObject API operations)

  • AWS Lambda function execution activity (the Invoke API)

Data events are disabled by default when you create a trail. To record CloudTrail data events, you must explicitly add the supported resources or resource types for which you want to collect activity to a trail. For more information, see Creating a Trail, Data Events, and Services That Support Logging Data Events.

Additional charges apply for logging data events. For CloudTrail pricing, see AWS CloudTrail Pricing.

What Is CloudTrail Event History?

CloudTrail event history provides a viewable, searchable, and downloadable record of the past 90 days of CloudTrail events. You can use this history to gain visibility into actions taken in your AWS account in the AWS Management Console, AWS SDKs, command line tools, and other AWS services. You can customize your view of event history in the CloudTrail console by selecting which columns are displayed. For more information about what is included in CloudTrail event history, see Services Supported by CloudTrail Event History and Resource Types Supported by CloudTrail Event History.

What Are Trails?

A trail is a configuration that enables delivery of CloudTrail events to an Amazon S3 bucket, CloudWatch Logs, and CloudWatch Events. You can use a trail to filter the CloudTrail events you want delivered, encrypt your CloudTrail event log files with an AWS KMS key, and set up Amazon SNS notifications for log file delivery.

How Do You Manage CloudTrail?

CloudTrail Console

You can use and manage the CloudTrail service with the AWS CloudTrail console. The console provides a user interface for performing many CloudTrail tasks such as:

  • Viewing recent events and event history for your AWS account

  • Downloading a filtered or complete file of the last 90 days of events

  • Creating and editing CloudTrail trails

  • Configuring CloudTrail trails, including selecting an Amazon S3 bucket, setting a prefix, configuring delivery to CloudWatch Logs, using AWS KMS keys for encryption, and enabling Amazon SNS notifications for log file delivery

For more information about the AWS Management Console, see AWS Management Console.

CloudTrail CLI

The AWS Command Line Interface is a unified tool that you can use to interact with CloudTrail from the command line. For more information, see the AWS Command Line Interface User Guide. For a complete list of the available CloudTrail CLI commands, see Available Commands.

CloudTrail APIs

In addition to the console and the CLI, you can also use the CloudTrail RESTful APIs to program CloudTrail directly. For more information, see the AWS CloudTrail API Reference.


As an alternative to using the CloudTrail API, you can use one of the AWS SDKs. Each SDK consists of libraries and sample code for various programming languages and platforms. The SDKs provide a convenient way to create programmatic access to CloudTrail. For example, you can use the SDKs to sign requests cryptographically, manage errors, and retry requests automatically. For more information, see the Tools For AWS page.

How Do You Control Access to CloudTrail?

AWS Identity and Access Management is a web service that enables Amazon Web Services (AWS) customers to manage users and user permissions. Use IAM to create individual users for anyone who needs access to AWS CloudTrail. Create an IAM user for yourself as well, give that IAM user administrative privileges, and use that IAM user for all of your work. By creating individual IAM users for people accessing your account, you can give each IAM user a unique set of security credentials. You can also grant different permissions to each IAM user. If necessary, you can change or revoke an IAM user’s permissions any time. For more information, see Controlling User Permissions for CloudTrail.

How Do You Log Management and Data Events?

By default, trails log all management events for your AWS account and don't include data events. You can choose to create or update trails to log data events. Only events that match your trail settings are delivered to your Amazon S3 bucket and Amazon CloudWatch Events, and optionally to an Amazon CloudWatch Logs log group. If the event doesn't match the settings for a trail, the trail doesn't log the event. For more information, see Logging Data and Management Events for Trails.

How Do You Perform Monitoring with CloudTrail?

CloudWatch Logs and CloudTrail

Amazon CloudWatch is a web service that collects and tracks metrics to monitor your Amazon Web Services (AWS) resources and the applications that you run on AWS. Amazon CloudWatch Logs is a feature of CloudWatch that you can use specifically to monitor log data. Integration with CloudWatch Logs enables CloudTrail to send events containing API activity in your AWS account to a CloudWatch Logs log group. CloudTrail events that are sent to CloudWatch Logs can trigger alarms according to the metric filters you define. You can optionally configure CloudWatch alarms to send notifications or make changes to the resources that you are monitoring based on log stream events that your metric filters extract. Using CloudWatch Logs, you can also track CloudTrail events alongside events from the operating system, applications, or other AWS services that are sent to CloudWatch Logs. For more information, see Monitoring CloudTrail Log Files with Amazon CloudWatch Logs.

How Does CloudTrail Behave Regionally and Globally?

A trail can be applied to all regions or a single region. As a best practice, create a trail that applies to all regions in the AWS partition in which you are working. This is the default setting when you create a trail in the CloudTrail console.


Turning on a trail means that you create a trail and start delivery of CloudTrail event log files to an Amazon S3 bucket. In the CloudTrail console, logging is turned on automatically when you create a trail.

What are the advantages of applying a trail to all regions?

A trail that applies to all regions has the following advantages:

  • The configuration settings for the trail apply consistently across all regions.

  • You receive CloudTrail events from all regions in a single S3 bucket and optionally in a CloudWatch Logs log group.

  • You manage trail configuration for all regions from one location.

  • You immediately receive events from a new region. When a new region launches, CloudTrail automatically creates a trail for you in the new region with the same settings as your original trail.

  • You can create trails in regions that you don't use often to monitor for unusual activity.

What happens when you apply a trail to all regions?

When you apply a trail to all regions, CloudTrail uses the trail that you create in a particular region to create trails with identical configurations in all other regions in your account.

This has the following effects:

  • CloudTrail delivers log files for account activity from all regions to the single Amazon S3 bucket that you specify, and optionally to a CloudWatch Logs log group.

  • If you configured an Amazon SNS topic for the trail, SNS notifications about log file deliveries in all regions are sent to that single SNS topic.

  • If you enabled log file integrity validation, log file integrity validation is enabled in all regions for the trail. For information about log file integrity validation, see Validating CloudTrail Log File Integrity.

Multiple trails per region

If you have different but related user groups such as developers, security personnel, and IT auditors, you can create multiple trails per region. This allows each group to receive its own copy of the log files.

CloudTrail supports five trails per region. A trail that applies to all regions counts as one trail in every region.

The following example is a region with five trails:

  • You create two trails in the US West (N. California) Region that apply only to this region.

  • You create two more trails in US West (N. California) Region that apply to all regions.

  • You create a trail in the Asia Pacific (Sydney) Region that applies to all regions. This trail also exists as a trail in the US West (N. California) Region.

You can see a list of your trails in all regions on the Trails page of the CloudTrail console. For more information, see Updating a Trail. For CloudTrail pricing, see AWS CloudTrail Pricing.

AWS Security Token Service (AWS STS) and CloudTrail

AWS STS is a service that has a global endpoint and that also supports region-specific endpoints. An endpoint is a URL that is the entry point for web service requests. For example, is the US West (Oregon) regional entry point for the AWS CloudTrail service. Regional endpoints help reduce latency in your applications.

When you use an AWS STS region-specific endpoint, the trail in that region delivers only the AWS STS events that occur in that region. For example, if you are using the endpoint, the trail in us-west-2 delivers only the AWS STS events that originate from us-west-2. For more information about AWS STS regional endpoints, see Activating and Deactivating AWS STS in an AWS Region in the IAM User Guide.

For a complete list of AWS regional endpoints, see AWS Regions and Endpoints in the AWS General Reference. For details about events from the global AWS STS endpoint, see About global service events.

About global service events

For most services, events are sent to the region where the action happened. For global services such as IAM, AWS STS, and Amazon CloudFront, events are delivered to any trail that includes global services. For example, Route 53 actions are logged in the US East (N. Virginia) Region.

To avoid receiving duplicate global service events, remember the following:

  • Global service events are delivered to trails that have the Apply trail to all regions option enabled. Events are delivered from a single region to the bucket for the trail.

  • If you have a single region trail, you should include global services.

  • If you have multiple single region trails, you should enable global services in only one of the trails.


  1. You have a trail with the Apply trail to all regions option enabled. By default, this trail logs global service events.

  2. You have multiple single region trails.

  3. You do not need to include global services for the single region trails. Global service events are delivered for the first trail.


When you create or update a trail with the AWS CLI, AWS SDKs, or CloudTrail API, you can specify whether to include or exclude global service events for trails. You cannot configure global service event logging from the CloudTrail console.

How Does CloudTrail Relate to Other AWS Monitoring Services?

CloudTrail adds another dimension to the monitoring capabilities already offered by AWS; it does not change or replace logging features you might already be using such as those for Amazon S3 or Amazon CloudFront subscriptions. Amazon CloudWatch focuses on performance monitoring and system health; CloudTrail focuses on API activity. While CloudTrail does not report on system performance or health, you can use CloudTrail with CloudWatch alarms to notify you about activity that you might be interested in.

Partner Solutions

AWS partners with third-party specialists in logging and analysis to provide solutions that leverage CloudTrail output. For more information, visit the CloudTrail detail page at AWS CloudTrail.