Amazon CloudWatch Logs lets you monitor, store, and access your log files from Amazon Elastic Compute Cloud (Amazon EC2) instances, Amazon CloudTrail, Route 53, and other sources. You can then retrieve the associated log data from CloudWatch Logs using the Amazon CloudWatch console, the CloudWatch Logs commands in the AWS CLI, the CloudWatch Logs API, or the CloudWatch Logs SDK.
CloudWatch Logs uses an agent on your instance to monitor log files and send their data to CloudWatch. You can also configure CloudWatch Logs to collect log data from other AWS services such as Amazon Route 53, Amazon S3, and Amazon EC2. For more information, see What Is Amazon CloudWatch Logs?
To write a custom event string to Amazon CloudWatch Logs, you can use the CloudWatch Logs agent to push log data to CloudWatch. For more information about the CloudWatch Logs agent, see Installing and Configuring the CloudWatch Logs Agent.