Before you delete a gateway volume, make sure there are no iSCSI connections to the volume you are deleting. You should also make sure there is no snapshot in progress. You can use the Amazon Elastic Compute Cloud (Amazon EC2) API to query snapshots on the volume you are deleting and check the snapshot status. For more information, go to DescribeSnapshots in the Amazon Elastic Compute Cloud API Reference.
In the request, you must provide the Amazon Resource Name (ARN) of the storage volume you want to delete.