Use CreateTrail with an AWS SDK or CLI

// Routine which creates an AWS CloudTrail trail.
/*!
  \param trailName: The name of the CloudTrail trail.
  \param bucketName: The Amazon S3 bucket designate for publishing logs.
  \param clientConfig: Aws client configuration.
  \return bool: Function succeeded.
*/
bool AwsDoc::CloudTrail::createTrail(const Aws::String trailName,
                                     const Aws::String bucketName,
                                     const Aws::Client::ClientConfiguration &clientConfig) {
    Aws::CloudTrail::CloudTrailClient trailClient(clientConfig);
    Aws::CloudTrail::Model::CreateTrailRequest request;
    request.SetName(trailName);
    request.SetS3BucketName(bucketName);

    Aws::CloudTrail::Model::CreateTrailOutcome outcome = trailClient.CreateTrail(
            request);
    if (outcome.IsSuccess()) {
        std::cout << "Successfully created trail " << trailName << std::endl;
    }
    else {
        std::cerr << "Failed to create trail " << trailName <<
                  ": " << outcome.GetError().GetMessage() << std::endl;
    }

    return outcome.IsSuccess();
}

To create a trail

The following create-trail command creates a multi-region trail named Trail1 and specifies an S3 bucket:

aws cloudtrail create-trail --name Trail1 --s3-bucket-name my-bucket --is-multi-region-trail

Output:

{
  "IncludeGlobalServiceEvents": true,
  "Name": "Trail1",
  "TrailARN": "arn:aws:cloudtrail:us-west-2:123456789012:trail/Trail1",
  "LogFileValidationEnabled": false,
  "IsMultiRegionTrail": true,
  "S3BucketName": "my-bucket"
}

Example 1: Creates a trail that will use the bucket 'mycloudtrailbucket' for log file storage.

New-CTTrail -Name "awscloudtrail-example" -S3BucketName "amzn-s3-demo-bucket"

Example 2: Creates a trail that will use the bucket 'mycloudtrailbucket' for log file storage. The S3 objects representing the logs will have a common key prefix of 'mylogs'. When new logs are delivered to the bucket a notification will be sent to the SNS topic 'mlog-deliverytopic'. This example using splatting to supply the parameter values to the cmdlet.

$params = @{
    Name="awscloudtrail-example"
    S3BucketName="amzn-s3-demo-bucket"
    S3KeyPrefix="mylogs"
    SnsTopicName="mlog-deliverytopic"
}      
New-CTTrail @params

require 'aws-sdk-cloudtrail' # v2: require 'aws-sdk'
require 'aws-sdk-s3'
require 'aws-sdk-sts'

def create_trail_example(s3_client, sts_client, cloudtrail_client, trail_name, bucket_name)
  resp = sts_client.get_caller_identity({})
  account_id = resp.account

  # Attach policy to an Amazon Simple Storage Service (S3) bucket.
  s3_client.create_bucket(bucket: bucket_name)
  begin
    policy = {
      'Version' => '2012-10-17',
      'Statement' => [
        {
          'Sid' => 'AWSCloudTrailAclCheck20150319',
          'Effect' => 'Allow',
          'Principal' => {
            'Service' => 'cloudtrail.amazonaws.com'
          },
          'Action' => 's3:GetBucketAcl',
          'Resource' => "arn:aws:s3:::#{bucket_name}"
        },
        {
          'Sid' => 'AWSCloudTrailWrite20150319',
          'Effect' => 'Allow',
          'Principal' => {
            'Service' => 'cloudtrail.amazonaws.com'
          },
          'Action' => 's3:PutObject',
          'Resource' => "arn:aws:s3:::#{bucket_name}/AWSLogs/#{account_id}/*",
          'Condition' => {
            'StringEquals' => {
              's3:x-amz-acl' => 'bucket-owner-full-control'
            }
          }
        }
      ]
    }.to_json

    s3_client.put_bucket_policy(
      bucket: bucket_name,
      policy: policy
    )
    puts "Successfully added policy to bucket #{bucket_name}"
  end

  begin
    cloudtrail_client.create_trail({
                                     name: trail_name, # required
                                     s3_bucket_name: bucket_name # required
                                   })

    puts "Successfully created trail: #{trail_name}."
  rescue StandardError => e
    puts "Got error trying to create trail #{trail_name}:\n #{e}"
    puts e
    exit 1
  end