customKeyStoreId

Creates the KMS key in the specified custom key store. The ConnectionState of the custom key store must be CONNECTED. To find the CustomKeyStoreID and ConnectionState use the DescribeCustomKeyStores operation.

This parameter is valid only for symmetric encryption KMS keys in a single Region. You cannot create any other type of KMS key in a custom key store.

When you create a KMS key in an CloudHSM key store, KMS generates a non-exportable 256-bit symmetric key in its associated CloudHSM cluster and associates it with the KMS key. When you create a KMS key in an external key store, you must use the XksKeyId parameter to specify an external key that serves as key material for the KMS key.