I've never had an Oracle Cloud server. However, I do image backups of the server once a month, then test them in a VM, After hearing so much about Borg, I finally pulled the trigger and ran it from the cli for a while. Then I deployed Borg UI, and that's pretty amazing. I used to use Duplicati, but while Duplicati seems great at making backups, it's not so keen about doing restores. At least, that's my experience.