AWS SDK Version 3 for .NET
API Reference

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Creates a friendly name for a KMS key.

Adding, deleting, or updating an alias can allow or deny permission to the KMS key. For details, see ABAC for KMS in the Key Management Service Developer Guide.

You can use an alias to identify a KMS key in the KMS console, in the DescribeKey operation and in cryptographic operations, such as Encrypt and GenerateDataKey. You can also change the KMS key that's associated with the alias (UpdateAlias) or delete the alias (DeleteAlias) at any time. These operations don't affect the underlying KMS key.

You can associate the alias with any customer managed key in the same Amazon Web Services Region. Each alias is associated with only one KMS key at a time, but a KMS key can have multiple aliases. A valid KMS key is required. You can't create an alias without a KMS key.

The alias must be unique in the account and Region, but you can have aliases with the same name in different Regions. For detailed information about aliases, see Using aliases in the Key Management Service Developer Guide.

This operation does not return a response. To get the alias that you created, use the ListAliases operation.

The KMS key that you use for this operation must be in a compatible key state. For details, see Key states of KMS keys in the Key Management Service Developer Guide.

Cross-account use: No. You cannot perform this operation on an alias in a different Amazon Web Services account.

Required permissions

For details, see Controlling access to aliases in the Key Management Service Developer Guide.

Related operations:

Eventual consistency: The KMS API follows an eventual consistency model. For more information, see KMS eventual consistency.


For .NET Core this operation is only available in asynchronous form. Please refer to CreateAliasAsync.

Namespace: Amazon.KeyManagementService
Assembly: AWSSDK.KeyManagementService.dll
Version: 3.x.y.z


public virtual CreateAliasResponse CreateAlias(
         CreateAliasRequest request


Type: Amazon.KeyManagementService.Model.CreateAliasRequest

Container for the necessary parameters to execute the CreateAlias service method.

Return Value

The response from the CreateAlias service method, as returned by KeyManagementService.


AlreadyExistsException The request was rejected because it attempted to create a resource that already exists.
DependencyTimeoutException The system timed out while trying to fulfill the request. You can retry the request.
InvalidAliasNameException The request was rejected because the specified alias name is not valid.
KMSInternalException The request was rejected because an internal exception occurred. The request can be retried.
KMSInvalidStateException The request was rejected because the state of the specified resource is not valid for this request. This exceptions means one of the following: The key state of the KMS key is not compatible with the operation. To find the key state, use the DescribeKey operation. For more information about which key states are compatible with each KMS operation, see Key states of KMS keys in the Key Management Service Developer Guide. For cryptographic operations on KMS keys in custom key stores, this exception represents a general failure with many possible causes. To identify the cause, see the error message that accompanies the exception.
LimitExceededException The request was rejected because a quota was exceeded. For more information, see Quotas in the Key Management Service Developer Guide.
NotFoundException The request was rejected because the specified entity or resource could not be found.


The following example creates an alias for the specified KMS key.

To create an alias

var client = new AmazonKeyManagementServiceClient();
var response = client.CreateAlias(new CreateAliasRequest 
    AliasName = "alias/ExampleAlias", // The alias to create. Aliases must begin with 'alias/'. Do not use aliases that begin with 'alias/aws' because they are reserved for use by AWS.
    TargetKeyId = "1234abcd-12ab-34cd-56ef-1234567890ab" // The identifier of the KMS key whose alias you are creating. You can use the key ID or the Amazon Resource Name (ARN) of the KMS key.


Version Information

.NET Framework:
Supported in: 4.5 and newer, 3.5

See Also