Creating a CMK

This section describes how to create a CMK on the KMS console.

Constraints

• You can create up to 100 CMKs, excluding default master keys.

• Aliases of default master keys end with /default. Therefore, in choosing aliases for your CMKs, do not use aliases ending with /default.

• KMS does not limit the number of times that a CMK can be called.

Scenarios

• Encrypt data in OBS

• Encrypt data in EVS

• Encrypt data in IMS

• Encrypt an RDS DB instance

• Direct encryption and decryption of small volumes of data

• DEK encryption and decryption for user applications

Creating a CMK

1. Log in to the management console.

2. Click in the upper left corner of the management console and select a region or project.

3. Click . Choose Security > Key Management Service. The Key Management Service page is displayed.

4. Click Create Key in the upper right corner.

5. Configure parameters in the Create Key dialog box.

   • Alias is the alias of the CMK to be created.

     Note

     • You can enter digits, letters, underscores (_), hyphens (-), colons (:), and slashes (/).

     • You can enter up to 255 characters.

   • Key Algorithm: Select a key algorithm. For more information, see Table 1.

     Table 1 Key algorithms supported by KMS

     Key Type	Algorithm Type	Key Specifications	Description	Usage
     Symmetric key	AES	AES_256	AES symmetric key	Encrypts and decrypts a small amount of data or data keys.
     Asymmetric key	RSA	RSA_2048 RSA_3072 RSA_4096	RSA asymmetric password	Encrypts and decrypts a small amount of data or creates digital signatures.
     	ECC	EC_P256 EC_P384	Elliptic curve recommended by NIST	Digital signature

   • Usage: Select SIGN_VERIFY or ENCRYPT_DECRYPT.

     • For a symmetric key, the default value is ENCRYPT_DECRYPT.

     • For RSA asymmetric keys, select ENCRYPT_DECRYPT or SIGN_VERIFY. The default value is SIGN_VERIFY.

     • For an ECC asymmetric key, the default value is SIGN_VERIFY.

     Note

     The key usage can only be configured during key creation and cannot be modified afterwards.

   • (Optional) Description is the description of the CMK.

     Note

     You can enter up to 255 characters.

6. (Optional) Add tags to the CMK as needed, and enter the tag key and tag value.

   Note

   • When a CMK has been created without any tag, you can add a tag to the CMK later as necessary. Click the alias of the CMK, click the Tags tab, and click Add Tag.

   • The same tag (including tag key and tag value) can be used for different CMKs. However, under the same CMK, one tag key can have only one tag value.

   • A maximum of 20 tags can be added for one CMK.

   • If you want to delete a tag from the tag list when adding multiple tags, you can click Delete in the row where the tag to be added is located to delete the tag.

7. Click OK. A message is displayed in the upper right corner of the page, indicating that the key is created successfully.

   In the CMK list, you can view created CMKs. The default status of a CMK is Enabled.

Related Operations

• For details about how to upload objects with server-side encryption, see section "Uploading a File with Server-Side Encryption" in the Object Storage Service User Guide.

• For details about how to encrypt data on EVS disks, see section "Creating an EVS Disk" in the Elastic Volume Service User Guide.

• For details about how to encrypt private images, see section "Encrypting an Image" in the Image Management Service User Guide.

• For details about how to create a DEK and a plaintext-free DEK, see sections "Creating a DEK" and "Creating a Plaintext-Free DEK" in the Key Management Service API Reference.

• For details about how to encrypt and decrypt a DEK for a user application, see sections "Encrypting a DEK" and "Decrypting a DEK" in the Key Management Service API Reference.

last updated: 2024-11-08 14:06 UTC - commit: 5674aac1874f8e8728192583f58d6e232d714273