AWS Monitoring Solutions: CloudTrail vs. CloudWatch

Quick Definition: CloudTrail is for tracking account activity and auditing, while CloudWatch is for monitoring and managing the performance and health of AWS resources and applications. They have distinct use cases and provide different insights into AWS operations.

Every second counts in the fast-paced world of IT infrastructure. Ensuring seamless operations in AWS hinges on robust monitoring and logging.

With options like AWS's CloudTrail and CloudWatch at your disposal, how do you decide which tool fits best? Dive in as we juxtapose AWS CloudTrail and CloudWatch, shedding light on their distinct offerings.

What is AWS CloudTrail?

Amazon CloudTrail is an AWS service used to track user activity and API usage on AWS and in hybrid and multi-cloud environments. It provides IT teams with a comprehensive audit trail, ensuring accountability and facilitating diagnostics in cloud operations.

How AWS CloudTrail Works

Account management has deep roots. Going back to ancient times, diligent record-keepers used clay tablets to document transactions: the who, what, and when of business. Fast-forward to today, and AWS CloudTrail continues that tradition in the digital realm. It meticulously tracks who interacts with a specific resource, what action they took, and the timestamp of that activity.

So, while CloudTrail might seem ultra-modern, it's simply a digital evolution of age-old practices. When navigating its features, remember the legacy of detailed record-keeping that it upholds.

Three types of events apply to CloudTrail: management events, data events, and insight events. With CloudTrail Insights, you can identify and analyze particularly unusual activity.

IT logging goes way back. I remember one co-worker in my telecom days who would write scripts that regularly accessed servers to pull down logs. He would set up repositories to store the logs for later troubleshooting and analysis. 

AWS CloudTrail automates all that for us. CloudTrail records account activity as events and makes them available for review. A new record appears in CloudTrail within 15 minutes after the event. Events in AWS Free Tier are stored for 90 days. Examples are ConsoleLogin, DeleteBucket, and CreateTrail. 

To view all of these events, simply click on "Event History" within your CloudTrail interface. Additionally, you can create an Athena table within an S3 bucket, allowing for later querying and in-depth analysis. Here's a concise overview of AWS CloudTrail:

CloudTrail Use Cases and Examples

We already saw how to use CloudTrail to audit account activity across AWS services. It’s also useful to identify events that may raise flags in terms of security or to troubleshoot operational issues. 

Imagine a customer telling you they can't access certain services. Your immediate questions should be: "What was altered?" and "Who made the change?" By using CloudTrail, examining logs, or utilizing tools like Athena, you can pinpoint the issue. It's possible changes were made to a security group, access control list, or another security feature. Alternatively, a server application might have been modified. It's detective time for you!

You can also easily track logins (or login failures) to an account and use CloudWatch to alert you to issues. So, what is CloudWatch? Let’s take a look.

AWS CloudWatch

Amazon CloudWatch is an AWS service designed to oversee resources and applications on AWS. It also extends its capabilities to on-premises environments and other cloud platforms, ensuring comprehensive monitoring across diverse infrastructures.

How AWS CloudWatch Works

Both AWS CloudTrail and AWS CloudWatch are monitoring and logging tools. Output from AWS CloudWatch can be collected and analyzed in much the same way as CloudTrail. You can slice, dice, and even stream it into machine learning and data analytics functions. 

What is different about CloudWatch is that it focuses more on AWS resources rather than accounts. CloudTrail monitors services every five minutes by default but can be set to one-minute intervals for a higher cost.

Another fascinating feature of CloudWatch is that it can automatically trigger actions and notifications when a particular condition is reached. CloudWatch includes metrics, logs, events, and alarms. I can tell you the limits you set for your thresholds will determine how many alarms you will get. I once worked with an automated ticketing system that spits out hundreds of tickets because of low alarm thresholds. Always be sure to set reasonable alarm triggers.

That said, CloudTrail can use Simple Notification Service (SNS) to notify you of alarm conditions by sending messages to your email or phone. It can trigger Lambda or update a database based on your configured requests. As shown in the illustration below, CloudWatch can not only collect, monitor, and analyze – it can also take action.

CloudWatch Use Cases and Examples

You can do a lot with AWS CloudWatch. You can monitor applications and see what’s happening across systems and accounts. And you can keep an eye on the health of your infrastructure. You can even automate actions to resolve or work around issues quickly.

A simple example of CloudWatch monitoring is to set an alarm threshold for an EC2 instance. You may set up CloudWatch to email you when an instance stays at 80% utilization for five minutes.

Combining CloudWatch and CloudTrail offers another intriguing option. AWS provides detailed guides on such setups. You can use metrics and filters in CloudWatch to create alarms triggered by security group configuration changes, AWS Management Console sign-in failures, or IAM policy changes. CloudWatch sources CloudTrail logs for the appropriate alarm thresholds.

AWS CloudTrail vs. CloudWatch: Key Differences

While CloudTrail and CloudWatch both monitor AWS activities, they serve distinct purposes. CloudTrail focuses on AWS account actions, answering questions like "Who did what and when?" On the other hand, CloudWatch evaluates the performance of AWS services, examining the efficiency of your architectural components.

Additionally, their tracking intervals and primary use cases differ. CloudTrail identifies users altering your infrastructure, whereas CloudWatch diagnoses application issues and takes actions based on set metrics. It's also worth noting that their integrations with other AWS services are not the same.

Final Thoughts

Both CloudWatch and CloudTrail can handle vast amounts of data, including application logs, service logs, and account activity logs. Yet, they process distinct types of information. AWS also offers other monitoring and logging tools, such as EventBridge, VPC Flow Logs, and Custom Logs.

Understanding the nuances between these AWS services is crucial when shaping and overseeing your cloud architecture. For additional insights on AWS CloudTrail, refer to the CloudTrail Best Practices on the AWS website.

As we conclude, if you're looking to take the next step in your AWS journey, here's what we recommend:

• Elevate Your Skills: Dive into our CBT Nuggets training for the AWS Certified Solutions Architect – Associate - SAA-C03.

• For the Newbies: Pondering which AWS certification to pursue? Explore top recommendations in our guide: "What is the Best AWS Certification for New IT Pros."

• Further Reading: Delve into the value of the AWS Solutions Architect – Associate certification. Is the AWS Solutions Architect – Associate Worth It? Find out!