Hello Huy,
What type of backup were you attempting to schedule?
For Datastore scheduled backups you may find information in the Scheduled Backups document.
CloudSQL automated backups are to be performed as detailed in the Creating and Managing On-Demand and Automatic Backups document. Your database has been backed up frequently in the past. Your logs only show an error when updating the database today at 5:52:50, no backup-related errors. Have you followed the steps described in this document, to schedule your backups?
2017-02-09T15:00:00.636+00:00 - UNKNOWN_STATUS
2017-02-08T15:00:00.734+00:00 - UNKNOWN_STATUS
2017-02-07T15:00:00.405+00:00 - UNKNOWN_STATUS
.....
2016-12-02T15:00:00.553+00:00 - UNKNOWN_STATUS
2016-12-01T15:00:00.895+00:00 - UNKNOWN_STATUS
2016-11-30T15:00:00.324+00:00 - UNKNOWN_STATUS
2016-11-29T15:00:00.188+00:00 - SUCCESSFUL
2016-11-28T15:00:00.892+00:00 - SUCCESSFUL
2016-11-27T15:00:00.834+00:00 - SUCCESSFUL
Hello Huy,
We are unable to reproduce the “unknown status” error, as we can’t open a cloud shell from your project.