Description:
Optional. Specifies the KMS configuration for the one or more keys used to protect the backup. Values are of the form `projects//locations//keyRings//cryptoKeys/`. The keys referenced by kms_key_names must fully cover all regions of the backup's instance configuration. Some examples: * For single region instance configs, specify a single regional location KMS key. * For multi-regional instance configs of type GOOGLE_MANAGED, either specify a multi-regional location KMS key or multiple regional location KMS keys that cover all regions in the instance config. * For an instance config of type USER_MANAGED, please specify only regional location KMS keys to cover each region in the instance config. Multi-regional location KMS keys are not supported for USER_MANAGED instance configs.