How does CloudWatch find related telemetry? - Amazon CloudWatch
Where does the entity data come from?Where does service data come from?

How does CloudWatch find related telemetry?

The CloudWatch Explore related pane shows you metrics and logs that are related to each other, but how does that work?

Metrics and logs that are sent to CloudWatch can include an optional entity to which they are related. Typically, the entity will be a representation of what the telemetry is about. For example, a metric about CPU usage is about an Amazon EC2 instance, and will use that instance as its entity. When you view that metric in the Explore related pane, it shows you other telemetry for that same instance.

The topology map (map) in the Explore related pane displays the currently selected resource, along with related resources. For AWS resources, CloudWatch automatically displays other resources that it knows are related. For example, if you are viewing an Amazon EC2 instance, the map will also display any Amazon EBS volumes that are attached to the instance. Selecting a volume shows telemetry for the volume, and the map is updated to display resources related to the volume. It also displays resources that are part of the same service.

The entity information associated with your telemetry defines the resource that the telemetry is associated with, such as the Amazon EC2 instance. However, it can also include contextual data about the resource. For example, if you have a website application that includes resources such as an Amazon EC2 instance and a database, the entity information can include the website application as a service. In this case, the topology map shows the service as a related entity, and when you select it, it displays the instances and database. This can make finding all the telemetry for a service simpler.

Note

CloudWatch must have received telemetry with entity information within the last three hours in order to find related resources and telemetry.

There are different ways that CloudWatch gets entities for telemetry:

Besides recognizing the natural connections between resources, such as an instance resource and an attached volume resource, CloudWatch can also group resources by service. For example, a service might be a website application. An Amazon EC2 instance with a web server, and another with a database might both be part of the same service, and are connected on the topology map based on that service.

There are different ways that CloudWatch gets a service name for telemetry, including:

  • Application signals or otel instrumented telemetry use the OTEL_SERVICE_NAME environment variable used by supported OpenTelemetry instrumentation libraries to set the service name.

  • The CloudWatch agent configuration allows configuring a service name. For more information, see Configure CloudWatch agent service and environment names for related entities.

  • Kubernetes workloads use a corresponding name from the cluster, such as the Deployment, ReplicaSet, Pod, or Container, for the service name.

  • For Amazon EC2 workloads, the service can come from tags (the service, application, or app tags).

    Note

    To use tags to generate service names, you must first set up instance metadata for the Amazon EC2 instance.

  • When you are submitting your own telemetry, you can add service information to the data. For more information, see How to add related information to custom telemetry sent to CloudWatch.

  • When it cannot use the above, CloudWatch uses the name of the IAM role that sends the metrics as the service name. This, for example, can provide a service name for Amazon ECS telemetry.