AWS SDK Version 3 for .NET
API Reference

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Associates an existing alias with a different customer master key (CMK). Each CMK can have multiple aliases, but the aliases must be unique within the account and region. You cannot perform this operation on an alias in a different AWS account.

This operation works only on existing aliases. To change the alias of a CMK to a new value, use CreateAlias to create a new alias and DeleteAlias to delete the old alias.

Because an alias is not a property of a CMK, you can create, update, and delete the aliases of a CMK without affecting the CMK. Also, aliases do not appear in the response from the DescribeKey operation. To get the aliases of all CMKs in the account, use the ListAliases operation.

An alias name can contain only alphanumeric characters, forward slashes (/), underscores (_), and dashes (-). An alias must start with the word alias followed by a forward slash (alias/). The alias name can contain only alphanumeric characters, forward slashes (/), underscores (_), and dashes (-). Alias names cannot begin with aws; that alias name prefix is reserved by Amazon Web Services (AWS).


For .NET Core and PCL this operation is only available in asynchronous form. Please refer to UpdateAliasAsync.

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


public abstract UpdateAliasResponse UpdateAlias(
         String aliasName,
         String targetKeyId
Type: System.String

String that contains the name of the alias to be modified. The name must start with the word "alias" followed by a forward slash (alias/). Aliases that begin with "alias/aws" are reserved.

Type: System.String

Unique identifier of the customer master key to be mapped to the alias. Specify the key ID or the Amazon Resource Name (ARN) of the CMK. For example: Key ID: 1234abcd-12ab-34cd-56ef-1234567890ab Key ARN: arn:aws:kms:us-east-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab To get the key ID and key ARN for a CMK, use ListKeys or DescribeKey. To verify that the alias is mapped to the correct CMK, use ListAliases.

Return Value
The response from the UpdateAlias service method, as returned by KeyManagementService.


DependencyTimeoutException The system timed out while trying to fulfill the request. The request can be retried.
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. For more information about how key state affects the use of a CMK, see How Key State Affects Use of a Customer Master Key in the AWS Key Management Service Developer Guide.
NotFoundException The request was rejected because the specified entity or resource could not be found.

Version Information

.NET Framework:
Supported in: 4.5, 4.0, 3.5

Portable Class Library:
Supported in: Windows Store Apps
Supported in: Windows Phone 8.1
Supported in: Xamarin Android
Supported in: Xamarin iOS (Unified)
Supported in: Xamarin.Forms

See Also