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AWS Lambda Function Status Check

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AWS Lambda Function Status Check is a built-in Command Probe template that validates whether an AWS Lambda function exists and is in the Active state during a chaos experiment. Use it to assert that serverless functions stay available and invocable while a fault disrupts your application.

The probe runs the healthchecks utility bundled in the chaos probe image, queries the AWS Lambda API, and prints [Pass] when the function is in the Active state. The comparator marks the probe as passed when the output contains [Pass].

Built-in probe template

This is a built-in Command Probe template that runs on Kubernetes chaos infrastructure. Add it to an experiment from the probe library and customize its inputs. Go to Built-in probe templates to browse the full library, or go to Command probe to understand how command probes work.

Use cases​

Use this probe template to:

  • Verify that Lambda functions stay active during chaos experiments.
  • Validate function availability after configuration changes.
  • Monitor serverless application health and readiness.
  • Confirm that functions remain deployable and invocable.

How the probe works​

The template configures a Command Probe that runs healthchecks -name lambda-update-function. The utility resolves the function named in FUNCTION_NAME in the supplied REGION, calls the AWS Lambda API, and prints [Pass] when the function exists and is in the Active state. The comparator passes the probe when the output contains [Pass], and fails it otherwise.

Prerequisites​

  • Chaos infrastructure: A Kubernetes chaos infrastructure with network access to the AWS Lambda API endpoints.
  • AWS credentials: Cloud credentials available to the chaos infrastructure, with the permissions listed below.
  • Target function exists: The function named in FUNCTION_NAME exists in REGION.

Permissions required​

The credentials used by the probe need the following AWS actions:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "lambda:GetFunction"
      ],
      "Resource": "*"
    }
  ]
}

The probe uses the AWS credentials available to your chaos infrastructure. Go to AWS IAM integration to set up access through IAM Roles for Service Accounts (IRSA), or go to common policy for all AWS faults to apply a single superset policy.

Probe properties​

Command​

healthchecks -name lambda-update-function

Comparator​

TypeCriteriaValue
stringcontains[Pass]

The probe passes when the command output contains [Pass], which indicates that the Lambda function is in the Active state.

Environment variables​

VariableDescriptionRequiredDefault
FUNCTION_NAMEName of the Lambda function to check (for example, my-lambda-function).Yes-
REGIONAWS region where the Lambda function is located (for example, us-east-1).Yes-

Run properties​

PropertyDescriptionTypeDefault
timeoutMaximum time to wait for the probe to complete (for example, 30s, 1m, 5m).String300s
intervalTime between probe executions (for example, 5s, 30s, 1m).String10s
attemptNumber of retry attempts before the probe is marked as failed.Integer1
pollingIntervalTime between retry attempts (for example, 1s, 5s, 10s).String-
initialDelayInitial delay before the probe starts (for example, 0s, 10s, 30s).String-
stopOnFailureStop the experiment if the probe fails.Booleanfalse
verbosityLog verbosity level (info, debug, trace).String-

Troubleshooting​

AWS Lambda Function Status Check probe fails with an authorization error

The credentials available to the chaos infrastructure do not have the required Lambda permissions in the target region. Confirm that the IAM policy attached to the role or IRSA service account includes lambda:GetFunction, and that any policy condition allows the region passed in REGION.

AWS Lambda Function Status Check probe reports the function was not found

The function did not resolve in the supplied REGION. Verify that FUNCTION_NAME matches the function name exactly, that REGION matches the function region, and that the AWS account used by the credentials owns the function.

AWS Lambda Function Status Check probe fails because the function is not Active

The function exists but is in a Pending or Failed state, which can happen during configuration updates or while VPC-attached functions provision elastic network interfaces. Increase the run-property timeout and attempt count so the probe waits for the function to return to Active, and review the function's last update status in the AWS console.