Data encryption using AWS KMS

Storage Gateway uses SSL/TLS (Secure Socket Layers/Transport Layer Security) to encrypt data that is transferred between your gateway appliance and AWS storage. By default, Storage Gateway uses Amazon S3-Managed Encryption Keys (SSE-S3) to server-side encrypt all data it stores in Amazon S3. You have an option to use the Storage Gateway API to configure your gateway to encrypt data stored in the cloud using server-side encryption with AWS Key Management Service (SSE-KMS) keys.

Important

When you use an AWS KMS key for server-side encryption, you must choose a symmetric key. Storage Gateway does not support asymmetric keys. For more information, see Using symmetric and asymmetric keys in the AWS Key Management Service Developer Guide.

Encrypting a file share

For a file share, you can configure your gateway to encrypt your objects with AWS KMS–managed keys by using SSE-KMS. For information on using the Storage Gateway API to encrypt data written to a file share, see CreateNFSFileShare in the AWS Storage Gateway API Reference.

Encrypting a volume

For cached and stored volumes, you can configure your gateway to encrypt volume data stored in the cloud with AWS KMS–managed keys by using the Storage Gateway API. You can specify one of the managed keys as the KMS key. The key that you use to encrypt your volume can't be changed after the volume is created. For information on using the Storage Gateway API to encrypt data written to a cached or stored volume, see CreateCachediSCSIVolume or CreateStorediSCSIVolume in the AWS Storage Gateway API Reference.

Encrypting a tape

For a virtual tape, you can configure your gateway to encrypt tape data stored in the cloud with AWS KMS–managed keys by using the Storage Gateway API. You can specify one of the managed keys as the KMS key. The key that you use to encrypt your tape data can't be changed after the tape is created. For information on using the Storage Gateway API to encrypt data written to a virtual tape, see CreateTapes in the AWS Storage Gateway API Reference.

When using AWS KMS to encrypt your data, keep the following in mind:

• Your data is encrypted at rest in the cloud. That is, the data is encrypted in Amazon S3.

• IAM users must have the required permissions to call the AWS KMS API operations. For more information, see Using IAM policies with AWS KMS in the AWS Key Management Service Developer Guide.

• If you delete or deactivate your AWS AWS KMS key or revoke the grant token, you can't access the data on the volume or tape. For more information, see Deleting KMS keys in the AWS Key Management Service Developer Guide.

• If you create a snapshot from a volume that is KMS-encrypted, the snapshot is encrypted. The snapshot inherits the volume's KMS key.

• If you create a new volume from a snapshot that is KMS-encrypted, the volume is encrypted. You can specify a different KMS key for the new volume.

  Note

  Storage Gateway doesn't support creating an unencrypted volume from a recovery point of a KMS-encrypted volume or a KMS-encrypted snapshot.

For more information about AWS KMS, see What is AWS Key Management Service?