EBS Encryption

• Benefits of EBS Encryption

  • Data at rest encryption within the volume
  • Encryption for data between instance and volume
  • Encrypted snapshots
  • Encrypted volumes created from those snapshots
  • Minimal impact on performance
  • Leverages KMS (AES-256 encryption)

• Encrypting Unencrypted EBS Volumes

  Steps:

  1. Create an unencrypted snapshot of the volume.
  2. Copy the snapshot, enabling encryption during the copy.
  3. Create a new volume from the encrypted snapshot.
  4. Attach the new encrypted volume to the original instance.

• Console Demonstration

  • The transcript includes steps on how to perform this in the AWS console.

• Shortcut

  • You can enable encryption directly when creating a volume from an unencrypted snapshot.

Important Notes

• Always delete unneeded snapshots and volumes for security and cost reasons.

Extras:

Can you encrypt a volume without taking a snapshot?

Unfortunately, no, you cannot directly encrypt an existing EBS volume without creating a snapshot. Here's why:

• In-Place Encryption is Not Supported: EBS's underlying mechanisms do not allow for modifying the encryption state of a volume on-the-fly. Encryption works at the block level, and changing the encryption status requires restructuring how the data is stored.
• Snapshots Preserve Encryption State: Snapshots capture a volume's full state, including its encryption. By creating an encrypted volume from a snapshot, you're essentially creating a new, encrypted copy of the original data.

Workarounds (With Caveats):

While you cannot directly encrypt without a snapshot, there are some less-than-ideal workarounds:

1. In-Place Encryption Tools: Some third-party tools claim to provide in-place encryption. Proceed with extreme caution as these often involve complex, low-level manipulations and risk data corruption.
2. Encryption at the File System Level: You could enable file-system-level encryption (e.g., LUKS on Linux). This encrypts data before it's written to the volume. However:
   • This won't encrypt existing data on the volume.
   • It adds performance overhead due to the additional encryption/decryption layer.

The Recommended Approach:

The standard and safest approach for encrypting an existing EBS volume is:

1. Snapshot the unencrypted volume.