**Example 1: To create a lifecycle hook** This example creates a lifecycle hook that will invoke on any newly launched instances, with a timeout of 4800 seconds. This is useful for keeping the instances in a wait state until the user data scripts have finished, or for invoking an AWS Lambda function using EventBridge. :: aws autoscaling put-lifecycle-hook \ --auto-scaling-group-name my-asg \ --lifecycle-hook-name my-launch-hook \ --lifecycle-transition autoscaling:EC2_INSTANCE_LAUNCHING \ --heartbeat-timeout 4800 This command produces no output. If a lifecycle hook with the same name already exists, it will be overwritten by the new lifecycle hook. For more information, see `Amazon EC2 Auto Scaling lifecycle hooks <https://docs.aws.amazon.com/autoscaling/ec2/userguide/lifecycle-hooks.html>`__ in the *Amazon EC2 Auto Scaling User Guide*. **Example 2: To send an Amazon SNS email message to notify you of instance state transitions** This example creates a lifecycle hook with the Amazon SNS topic and IAM role to use to receive notification at instance launch. :: aws autoscaling put-lifecycle-hook \ --auto-scaling-group-name my-asg \ --lifecycle-hook-name my-launch-hook \ --lifecycle-transition autoscaling:EC2_INSTANCE_LAUNCHING \ --notification-target-arn arn:aws:sns:us-west-2:123456789012:my-sns-topic \ --role-arn arn:aws:iam::123456789012:role/my-auto-scaling-role This command produces no output. For more information, see `Amazon EC2 Auto Scaling lifecycle hooks <https://docs.aws.amazon.com/autoscaling/ec2/userguide/lifecycle-hooks.html>`__ in the *Amazon EC2 Auto Scaling User Guide*. **Example 3: To publish a message to an Amazon SQS queue** This example creates a lifecycle hook that publishes a message with metadata to the specified Amazon SQS queue. :: aws autoscaling put-lifecycle-hook \ --auto-scaling-group-name my-asg \ --lifecycle-hook-name my-launch-hook \ --lifecycle-transition autoscaling:EC2_INSTANCE_LAUNCHING \ --notification-target-arn arn:aws:sqs:us-west-2:123456789012:my-sqs-queue \ --role-arn arn:aws:iam::123456789012:role/my-notification-role \ --notification-metadata "SQS message metadata" This command produces no output. For more information, see `Amazon EC2 Auto Scaling lifecycle hooks <https://docs.aws.amazon.com/autoscaling/ec2/userguide/lifecycle-hooks.html>`__ in the *Amazon EC2 Auto Scaling User Guide*.