> For the complete documentation index, see [llms.txt](https://developer.harness.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.harness.io/resilience-testing/chaos-engineering/faults/chaos-fault-categories/aws/aws-fault-tunables.md).

# Common AWS fault tunables

This section describes the common AWS-specific fault tunables.

#### Managed node group <a href="#managed-node-group" id="managed-node-group"></a>

Specifies whether the AWS EC2 instances are a part of the managed node groups. If the instances belong to the managed node groups, set the `MANAGED_NODEGROUP` environment variable to `enable`, otherwise set it to `disable`. The default value is `disabled`.

The following YAML snippet illustrates the use of this environment variable:

```yaml
# it provided as enable if instances are part of self managed groups <a href="#it-provided-as-enable-if-instances-are-part-of-self-managed-groups" id="it-provided-as-enable-if-instances-are-part-of-self-managed-groups"></a>
# it is applicable for [ec2-terminate-by-id, ec2-terminate-by-tag] <a href="#it-is-applicable-for-ec2-terminate-by-id-ec2-terminate-by-tag" id="it-is-applicable-for-ec2-terminate-by-id-ec2-terminate-by-tag"></a>
apiVersion: litmuschaos.io/v1alpha1
kind: ChaosEngine
metadata:
  name: engine-nginx
spec:
  engineState: "active"
  chaosServiceAccount: litmus-admin
  experiments:
  - name: ec2-terminate-by-tag
    spec:
      components:
        env:
        # if instance is part of a managed node-group
        # supports enable and disable values, default value: disable
        - name: MANAGED_NODEGROUP
          value: 'enable'
        # region for the EC2 instance
        - name: REGION
          value: 'us-east-1'
        # tag of the EC2 instance
        - name: INSTANCE_TAG
          value: 'key:value'
        - name: TOTAL_CHAOS_DURATION
          VALUE: '60'
```