Upload files from on-prem to Cloud Storage and ensure objects are encrypted with customer-supplied encryption keys. What should you do?

To upload files to Cloud Storage with customer-supplied encryption keys (CSEK) using gsutil, the recommended method is to configure the encryption key in a .boto configuration file. gsutil automatically detects and uses the key specified in this file for uploads to buckets that require CSEK. The incorrect options are: Setting the encryption key via gcloud config is not the correct mechanism for gsutil to pick up CSEK for uploads. gcloud config manages general gcloud properties, not gsutil encryption keys. While gsutil does have an --encryption-key flag, it's primarily used for decryption operations or for specifying a key for a single operation, not for consistently applying CSEK during uploads where the key needs to be managed for multiple objects or sessions. Creating the bucket with --encryption-key is not a valid gsutil command. Buckets themselves are not created with a specific CSEK; rather, individual objects within the bucket are encrypted with CSEK during upload.