# Running a failure mode assessment at the service level
<a name="next-gen-running-service-assessment"></a>

You can run a failure mode assessment from the console or using the AWS CLI. The assessment runs asynchronously. Typical completion time is 5 to 15 minutes depending on service complexity.

**Prerequisites**
+ The service's invoker role must be configured and accessible.
+ At least one resilience policy should be applied. Assessments without policies still run but produce fewer targeted findings.

**To start a failure mode assessment (console)**

1. Navigate to your service.

1. Choose **Failure mode guidance** and add any assertions about your service. For more information, see [Failure mode guidance](next-gen-failure-mode-guidance.md).

1. Choose **Run failure mode assessment**.

1. Wait for the assessment to complete (typically 5 to 15 minutes).

**To start a failure mode assessment (CLI)**

```
aws resiliencehubv2 start-failure-mode-assessment \
  --service-arn "arn:aws:resiliencehub:us-east-1:123456789012:service/checkout:abc123"
```

**To check assessment status**

```
aws resiliencehubv2 list-failure-mode-assessments \
  --service-arn "arn:aws:resiliencehub:..."
```

Status values progress as follows: `PENDING`, then `IN_PROGRESS`, then `SUCCESS` or `FAILED`.

During the assessment, Next generation Resilience Hub runs resource discovery in the background:

1. Next generation Resilience Hub assumes your invoker role.

1. Reads resources from your configured input sources (CloudFormation, tags, Terraform, or Amazon EKS).

1. Identifies parent-child relationships (for example, Auto Scaling group to Amazon EC2 instances).

1. Resilience Hub builds a topology of your service.

1. Builds a topology showing data flow and containment.

Once topology is complete, you can view it in the console:
+ **Graph view** – Visual map of resources and connections.
+ **Table view** – List of all discovered resources with metadata.
+ **JSON export** – Download the full topology for external analysis.