Elven Observability: Lambda Instrumentation

Prerequisites

OTel Collector installed on an EC2 instance
Documentation
Organization registered in Elven Observability
Lambda Function
Allow traffic from Lambda to the EC2 running the Collector if it is not publicly accessible: documentation

without serverless framework
with serverless framework

Instrumentation

Without Serverless Framework
Instrumentation is performed via the AWS console.

Configuring Environment Variables

Go to the Lambda function, scroll down, click on the Configuration tab, select the Environment variables section, and click Edit.

2. Add the following environment variables by clicking on Add Environment Variables.

				
					  AWS_LAMBDA_EXEC_WRAPPER="/opt/otel-handler" 
  OTEL_TRACES_SAMPLER="always_on" 
  OTEL_TRACES_EXPORTER="otlp" 
  OTEL_METRICS_EXPORTER="otlp" 
  OTEL_LOG_LEVEL="DEBUG" 
  OTEL_PROPAGATORS="tracecontext,baggage, xray" 
  OTEL_LAMBDA_TRACE_MODE="capture"

  OTEL_EXPORTER_OTLP_ENDPOINT="<EC2_URL_HERE>" 
  OTEL_SERVICE_NAME="<LAMBDA-NAME>"
  OTEL_RESOURCE_ATTRIBUTES="service.name=<LAMBDA_NAME>,environment=<ENVIRONMENT>"

Only the last three variables need to be modified:

EC2_URL_HERE: The EC2 IP address or DNS if it was configured
LAMBDA-NAME: The name of the service that will appear in traces and metrics
ENVIRONMENT: dev, hml, or prd, depending on the environment being instrumented

Configuring the Instrumentation Layer

In the Code tab, scroll down to the Layers section and click on Add a Layer.

2. Choose the Specify an ARN option and paste this ARN:
arn:aws:lambda:us-east-1:184161586896:layer:opentelemetry-nodejs-0_9_0:4

3. Finally, click Verify, then Add.

With Serverless Framework
This is done in the serverless.yaml file where the Lambdas are configured, as shown in the example below:

It’s important to note that this configuration must be done for each function!

The configurations are the same as those performed in Configuring Environment Variables and Configuring the Instrumentation Layer.

				
					org: <ORG_NAME> 
app: <APP_NAME> 
service: <SERVICE_NAME> 

provider: 
  name: aws 
  runtime: nodejs20.x 

functions: 
  <LAMBDA_NAME_1>:
    handler: <HANDLER> 
    
    layers: 
      - arn:aws:lambda:us-east-1:184161586896:layer:opentelemetry-nodejs-0_9_0:4

    environment: 
      AWS_LAMBDA_EXEC_WRAPPER: "/opt/otel-handler" 
      OTEL_TRACES_SAMPLER: "always_on" 
      OTEL_TRACES_EXPORTER: "otlp" 
      OTEL_METRICS_EXPORTER: "otlp" 
      OTEL_LOG_LEVEL: "DEBUG" 
      OTEL_LAMBDA_TRACE_MODE: "capture" 
      OTEL_PROPAGATORS: "tracecontext,baggage, xray"

      OTEL_EXPORTER_OTLP_ENDPOINT: "<EC2_URL_HERE>" 
      OTEL_SERVICE_NAME: "<LAMBDA_NAME>" 
      OTEL_RESOURCE_ATTRIBUTES: "service.name=<LAMBDA_NAME>,environment=<ENVIRONMENT>" 
  <LAMBDA_NAME_2>:
    handler: <HANDLER> 
    
    layers: 
      - arn:aws:lambda:us-east-1:184161586896:layer:opentelemetry-nodejs-0_9_0:4

    environment: 
      AWS_LAMBDA_EXEC_WRAPPER: "/opt/otel-handler" 
      OTEL_TRACES_SAMPLER: "always_on" 
      OTEL_TRACES_EXPORTER: "otlp" 
      OTEL_METRICS_EXPORTER: "otlp" 
      OTEL_LOG_LEVEL: "DEBUG" 
      OTEL_LAMBDA_TRACE_MODE: "capture" 
      OTEL_PROPAGATORS: "tracecontext,baggage, xray"

      OTEL_EXPORTER_OTLP_ENDPOINT: "<EC2_URL_HERE>" 
      OTEL_SERVICE_NAME: "<LAMBDA_NAME>" 
      OTEL_RESOURCE_ATTRIBUTES: "service.name=<LAMBDA_NAME>,environment=<ENVIRONMENT>"

Once done, simply deploy the changes.