All about AWS CloudWatch..

Most of the organizations are adopting cloud and migrating their applications to the AWS Cloud, they also need to ensure that cloud-based services like Amazon Web Services (AWS) and other resources are available to the business. Now, how do you ensure that these cloud services are not disabled? You can do that using an application monitoring tool like Amazon CloudWatch.

The Amazon CloudWatch service is among the efficient ways of monitoring AWS applications and resources running on the AWS platform. Using cloud-based monitoring, CloudWatch collects operational data through logs, metrics, and events that provide a unified view of AWS resources and applications.

What is Amazon CloudWatch?

Designed as an AWS component, Amazon CloudWatch provides cloud-based monitoring of AWS resources including – EC2 instances, elastic, load balancers, auto-scaling groups – along with other Amazon services like Amazon S3, SNS, SQS, and RDS. Amazon administrators can easily monitor multiple AWS instances and applications from a centralized dashboard.

Additionally, CloudWatch can also be used to:

• Detect any anomaly in your cloud environment.
• Create custom dashboards that include metrics of the AWS services that you use.
• Create and configure alarms that can monitor AWS metrics and initiate automated actions.
• Gain complete visibility into application performance, utilization of AWS resources, and overall health of your operations.

The Amazon CloudWatch primarily performs the following four actions:

1. Collect metrics and logs

In the first step, CloudWatch collects metrics and logs from all your AWS services (for example, AWS EC2 instances). CloudWatch retrieves these metrics from the repository. This can also include custom metrics entered into the repository.

Here are some AWS services that publish CloudWatch metrics – Amazon API Gateway, AppStream version 2.0, Amazon Athena, and Amazon CloudFront.

2. Monitor and visualize the data

Next, CloudWatch monitors and visualizes this data using CloudWatch dashboards that provide a single unified view of all your AWS applications, resources, and services (running in premise or on the cloud). Additionally, you can correlate your collected metrics and logs to perform a visual analysis of the overall health and current performance of your resources.

3. Act on an automated response to any changes.

In this step, CloudWatch executes an automated response to any operational changes using alarms. For instance, you can configure an alarm to start or terminate an EC2 instance when selected conditions are satisfied. You can also use alarms to start services like Amazon EC2 auto-scaling or Amazon SNS.

If a configured alarm is triggered, you can set up automated actions like auto-scaling.

4. Analyze your metrics

The final step is to analyze and visualize your collected metric and log data – that can enable better insight and understanding. You can perform real-time analysis using CloudWatch Metric Math which helps you dive deeper into your data.

What is the need for Cloud-Based monitoring?

Be it on the premise or on the cloud, every business needs to ensure that their applications and services are running smoothly and productively. In addition to both web and cloud applications, a cloud-based monitoring tool is essential for monitoring cloud platforms, infrastructure, and networks.

For any web application deployed on the cloud, every business owner has questions related to the:

• The overall bandwidth consumed by the application on a daily basis
• The number of online users that are using the application
• The overall performance of the application on the cloud
• The level of customer satisfaction with the application

Cloud-based monitoring services like CloudWatch enable you to track how your application is performing on the cloud. Additionally, you can identify any performance bottlenecks or issues, thus enabling you to eliminate them and improve your application performance. This can help in business growth in the long run.

With the increasing number and complexity of AWS services, it’s no longer feasible to manually monitor your applications and services, hence you need an automation tool like CloudWatch.

What are the benefits of Amazon CloudWatch?

Amazon CloudWatch offers the following 5 benefits to businesses:

1. Access all monitoring data from a single dashboard

Amazon CloudWatch allows you to monitor data from different services using a single dashboard. CloudWatch is natively integrated with over 70 AWS-related services. 

Cloud-based applications including AWS applications generate large volumes of data through metrics and logs. CloudWatch allows you to easily collect and integrate all data from various applications and services and provide a visual representation of the analyzed data on the dashboard. 

2. Collects and analyze metrics from AWS and on-premise applications

Thanks to its seamless integration with over 70 AWS services, CloudWatch can collect and publish metric data automatically. This includes 1-minute native – and customized – metrics with 1-second granularity. CloudWatch is also supported on a hybrid AWS architecture that uses both on-premises and cloud-based resources.

Using this metric and log data, you can now optimize your AWS services and resources to achieve the best performance and throughput.

3. Improve your operational efficiency and optimize your available resource

The Amazon CloudWatch service provides real-time insights into cloud operations that enables you to optimize operational efficiency and reduce costs. By monitoring the utilization of AWS resources, you can be better informed of the kind of workload capacities that you require for your applications.

Using configured alarms, CloudWatch can automate your actions based on preconfigured thresholds or based on machine learning algorithms that can detect anomalies in your metric data.

4. Improve operational visibility

With the Amazon CloudWatch service, you gain operational visibility across all your running applications, networks, infrastructure stacks, and other AWS services. For instance, you can use CloudWatch to monitor the memory usage and bandwidth for any application, so as to optimize them for better performance.

Additionally, you can perform metric-related mathematical operations to derive operational insights from your data. For instance, you can aggregate memory usage across multiple EC2 instances. As a result, you gain complete visibility of your entire system and can detect and resolve any performance issues.

5. Extract valuable insights

Finally, Amazon CloudWatch enables you to extract valuable and actionable insights from generated logs of different AWS services and applications. You can explore, analyze, and then visualize your log data to monitor data like memory usage, CPU utilization, and capacity usage.

With CloudWatch, you only need to pay for the log queries that you run, which can also scale with higher log volume and complexity.

How to create CloudWatch Dashboards?

Amazon CloudWatch dashboards are customizable dashboards that provide a unified view of all your AWS resources – including those that are located in different AWS regions. As an AWS administrator, you can create an unlimited number of CloudWatch dashboards on your AWS account. 

You can create the dashboard using the:

• CloudWatch console
• PutDashboard API

Here’s how you can create a CloudWatch dashboard using the CloudWatch console:

1. Open the CloudWatch console.

2. From the navigation pane, click Dashboards > Create a dashboard.

3. From the “Create new dashboard” box that appears, enter your dashboard name and then click “Create a dashboard.”

If you enter the dashboard name as “CloudWatch-Default,” your dashboard will be displayed on the CloudWatch home page. Alternatively, if you use the name “CloudWatch-Default-<Resource Group Name>,” the dashboard appears on the CloudWatch home page when you open the particular AWS resource group.

4. As required, perform any of the following actions in the “Add to this dashboard” box:

a. To add a graph to the dashboard:

- Select either Line or Stacked Area and then click Configure.

- From “Add metric graph” dialog box, choose the metrics to be included in the graph and then click “Create widget.”

b. To add a number that displays a metric on the dashboard:

•  Select Number and then click Configure.
•  Select metrics to be included in the graph from “Add metric graph” dialog box and then click “Create widget.”

c. For adding a text block to the dashboard:

•  Select Text and then click Configure.
• From the “New text widget” dialog box, choose “Markdown” and then add and format your text.
• Click “Create widget.”

5. Repeat Step 4 to add more dashboard widgets if required.

6. Save your dashboard. 

You can also create or modify a CloudWatch dashboard using the PutDashboard API function. Here are some of the common parameters that are using with this API:

• DashboardName (mandatory): specifies the dashboard name in String format.
• DashboardBody (mandatory): contains all the dashboard information including the widgets to be added and their location on the dashboard.

How to create and configure CloudWatch Alarms?

Amazon CloudWatch allows you to create both the following types of alarms:

Metric alarms monitor a single metric or a math metric that is based on a mathematical expression.

Composite alarms that are triggered only if the condition for all other configured alarms are satisfied.

You can also create an alarm that is based on:

• Static threshold of a single metric
• Anomaly detection
• Metric math expression

Here’s how you can create a CloudWatch alarm – based on a single metric - using the CloudWatch console:

1. Open the CloudWatch console

2. From the navigation pane, click Alarms > Create Alarm.

3. Select your metric and then perform either of the following actions:

• Select the service namespace containing the metrics that you want to include.
• Search for a metric in the search box and then press Enter.

4. From the “Graphed metrics” tab, perform the following actions:

• From Statistics, choose any of the available statistics or percentiles.
• From Period, specify the evaluation period of the alarm.
• Click “Select metric” to display the “Specify metric and conditions” page that shows all information of the metric and statistics that you have specified.

5. From the “Conditions” tab, perform the following actions:

• Specify the name and description of the alarm.
• Use the “Whenever <metric> is” field to specify the threshold value of the metric.
• Click “Additional configuration.” 
• In “Datapoints to alarm,” specify the number of evaluation periods (or data points) required to trigger the alarm.
• From “Missing data treatment,” configure the alarm settings in the event of any missing data points.
• Click Next.

6. From the “Notification” tab, select the Amazon SNS topic that should be notified when the alarm is triggered.

7. Select the respective options if you want the alarm to perform auto-scaling or any other EC2 actions.

8. In the “Preview and create” tab, preview the alarm settings and then click “Create alarm.”

Here’s how you can create a CloudWatch alarm – based on anomaly detection - using the CloudWatch console:

1. Perform Steps 1 to 4 as specified above.

2. From the “Conditions” tab, perform the following actions:

• Select the “Anomaly detection” option
• Use the “Whenever <metric> is” field to specify the range of metric value that can trigger the alarm.
• Specify the anomaly detection number in the “Anomaly detection threshold” field
• Click “Additional configuration.” 
• In “Datapoints to alarm,” specify the number of evaluation periods (or data points) required to trigger the alarm.
• From “Missing data treatment,” configure the alarm settings in the event of any missing data points.
• Click Next.

3. Perform Steps 6 to 8 (as specified above) to create the alarm.

Finally, here’s how you can create a CloudWatch alarm – based on a metric math expression - using the CloudWatch console:

1. Perform Steps 1 to 4 as specified in the first procedure.

2. Click “Add a math expression” to add a new row for the expression:

• Add a math expression under the “Details” column of the new row.
• Add a metric or another mathematical expression under the “Id” column.
• Add more math expressions if required.

3. Click “Select metric” to display the “Specify metric and conditions” page that shows all information of the metric math expression that you have specified.

4. Perform the remaining steps (as detailed from Steps 2d in the previous procedure.

5. Perform Steps 6 to 8 (as specified in the first procedure) to create the alarm.

Conclusion

Using the Amazon CloudWatch service, you can monitor cloud-based applications and other AWS services and troubleshoot any performance issues. With its single and centralized dashboard, AWS administrators now have complete visibility into applications and services running in the same or different AWS region.