Each CMK can have multiple aliases, but each alias points to only one
CMK. The alias name must be unique in the AWS account and region. To
simplify code that runs in multiple regions, use the same alias name,
but point it to a different CMK in each region.
Because an alias is not a property of a CMK, you can delete and change
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, use the ListAliases operation.
The alias name must begin with alias/
followed by a name, such as
alias/ExampleAlias
. It can contain only alphanumeric characters,
forward slashes (/), underscores (\_), and dashes (-). The alias name
cannot begin with alias/aws/
. The alias/aws/
prefix is reserved for
AWS managed CMKs.
The alias and the CMK it is mapped to must be in the same AWS account
and the same region. You cannot perform this operation on an alias in a
different AWS account.
To map an existing alias to a different CMK, call UpdateAlias.
The result of this operation varies with the key state of the CMK. For
details, see How Key State Affects Use of a Customer Master Key
in the AWS Key Management Service Developer Guide.