CloudWatch is a monitoring service for AWS cloud resources and the applications running on AWS. CloudWatch provides data and actionable insights to monitor applications, understand and respond to system-wide performance changes, optimize resource utilization, and get a unified view of operational health. CloudWatch can be used to collect and track metrics, set alarms, and automatically react to changes in your AWS resources.
In this article, we will take a look at how CloudWatch works and how it can be used to monitor and debug cloud applications.
CloudWatch collects data from AWS resources such as Amazon EC2 instances, Amazon DynamoDB tables, and Amazon RDS DB instances. This data is then used to generate metrics that can be used to monitor the performance of your resources and applications.
CloudWatch can also be used to collect log data from your resources and applications. This data can be used to troubleshoot issues and identify trends.
CloudWatch can be used to monitor your resources and applications in two ways:
Metrics: CloudWatch metrics are statistical data points that can be used to monitor the performance of your resources and applications. Metrics are generated from data that is collected by CloudWatch.
Logs: CloudWatch logs are records of the activity of your resources and applications. Logs can be used to troubleshoot issues and identify trends.
To use CloudWatch, you must first create an Amazon CloudWatch Logs group and an Amazon CloudWatch Logs stream.
Next, you need to install the CloudWatch Logs agent on your EC2 instances. The CloudWatch Logs agent is a software program that runs on your EC2 instances and sends log data to CloudWatch.
Once the CloudWatch Logs agent is installed and running on your EC2 instances, you can start sending log data to CloudWatch.
CloudWatch metric data is collected at five-minute intervals and is stored for two weeks.
To collect metrics with CloudWatch, you first need to create a metric filter. A metric filter matches a pattern in your log data and extracts the metric data from the log entry.
Next, you need to create a metric alarm. A metric alarm watches a metric and triggers an action when the metric exceeds a threshold.
CloudWatch log data is collected at one-minute intervals and is stored for 14 days.
To collect logs with CloudWatch, you first need to create a log group. A log group is a collection of logs with the same retention period.
Next, you need to create a log stream. A log stream is a sequence of log events from a single source.
Once you have created a log group and log stream, you can start sending log data to CloudWatch.
CloudWatch can be used to send notifications when a metric alarm is triggered. Notifications can be sent via Amazon SNS, Amazon SQS, or email.
To send notifications with CloudWatch, you first need to create an Amazon SNS topic. An Amazon SNS topic is a logical access point for allowing recipients to subscribe to your Amazon SNS messages.
Next, you need to create an Amazon SQS queue. An Amazon SQS queue is a buffer that stores messages until they are processed by a consumer.
Once you have created an Amazon SNS topic and Amazon SQS queue, you can configure your metric alarm to send notifications to them.
In this article, we have looked at how CloudWatch works and how it can be used to monitor and debug cloud applications. We have also seen how to set up CloudWatch and how to collect metrics and logs with CloudWatch. Finally, we have seen how to send notifications with CloudWatch.