Action set for AWS FIS

To create an experiment template, you must define one or more actions to make up the action set. For a list of predefined actions provided by AWS FIS, see Actions.

You can run an action only once during an experiment. To run the same AWS FIS action more than once in the same experiment, add it to the template multiple times using different names.

Action syntax

The following is the syntax for an action set.

{
    "actions": {
        "action_name": {
            "actionId": "aws:service:action-type",
            "description": "string",
            "parameters": {
                "name": "value"
             },
            "startAfter": ["action_name", ...],
            "targets": {
                "resource_type": "target_name"
            }
        }
    }
}

When you define an action, you provide the following:

action_name

A name for the action.

actionId

The action identifier.

description

An optional description.

parameters

Any action parameters.

startAfter

Any actions that must complete before this action can start. Otherwise, the action runs at the start of the experiment.

targets

Any action targets.

For examples, see Example actions.

Action duration

If an action includes a parameter that you can use to specify the duration of the action, by default, the action is considered complete only after the specified duration has elapsed. If you have set the emptyTargetResolutionMode experiment option to skip, then the action will complete immediately with status 'skipped' when no targets were resolved. For example, if you specify a duration of 5 minutes, AWS FIS considers the action complete after 5 minutes. It then starts the next action, until all actions are complete.

Duration can be either the length of time that an action condition is maintained or the length of time for which metrics are monitored. For example, latency is injected for the duration of time specified. For near instantaneous action types, such as terminating an instance, stop conditions are monitored for the duration of time specified.

If an action includes a post action within the action parameters, the post action runs after the action completes. The time it takes to complete the post action might cause a delay between the specified action duration and the beginning of the next action (or the end of the experiment, if all other actions are complete).

Example actions

The following are example actions.

Examples

• Stop EC2 instances

• Interrupt Spot Instances

• Disrupt network traffic

• Terminate EKS workers

Example: Stop EC2 instances

The following action stops the EC2 instances identified using the target named targetInstances. After two minutes, it restarts the target instances.

"actions": {
    "stopInstances": {
        "actionId": "aws:ec2:stop-instances",
        "parameters": {
            "startInstancesAfterDuration": "PT2M"
        },
        "targets": {
            "Instances": "targetInstances"
        }
    }
}

Example: Interrupt Spot Instances

The following action stops the Spot Instances identified using the target named targetSpotInstances. It waits two minutes before interrupting the Spot Instance.

"actions": {
    "interruptSpotInstances": {
        "actionId": "aws:ec2:send-spot-instance-interruptions",
        "parameters": {
            "durationBeforeInterruption": "PT2M"
        },
        "targets": {
            "SpotInstances": "targetSpotInstances"
        }
    }
}

Example: Disrupt network traffic

The following action denies traffic between the target subnets and subnets in other Availability Zones.

"actions": {
    "disruptAZConnectivity": {
        "actionId": "aws:network:disrupt-connectivity",
        "parameters": {
            "scope": "availability-zone",
            "duration": "PT5M"
        },
        "targets": {
            "Subnets": "targetSubnets"
        }
    }
}

Example: Terminate EKS workers

The following action terminates 50% of the EC2 instances in the EKS cluster identified using the target named targetNodeGroups.

"actions": {
    "terminateWorkers": {
        "actionId": "aws:eks:terminate-nodegroup-instances",
        "parameters": {
            "instanceTerminationPercentage": "50"
        },
        "targets": {
            "Nodegroups": "targetNodeGroups"
        }
    }
}