Right trying to keep this as brief as possible. Mum is retiring and has a bunch of paper copies of stuff she will need to keep for a few years. At most we are talking 50GB of stuff. She has her desktop and an O365 subscription (which will be staying). She saves items to her Local One Drive folder, which is then sync'd to the cloud. That however doesnt cover accidental deletions etc. I have an old Synology in the outbuilding. I was thinking using the OneDrive sync on there, we sync to from OneDrive to Synology. Then I would have the Synology back up do an encrypted incremental backup that would output to another cloud service, S3 or another O365 OneDrive account location. What do you guys think? Her own O365 account uses a secure password and MFA so that would cover someone accessing her local machine or her OneDrive account. Decent Encryption on the backup and secure password + MFA on the second cloud location would make that part more secure. Overthinking it? Missing something?
Onedrive will hold deleted items in its recycle bin for 30 days, however I totally agree that isn't really sufficient. I personally would use the Synology for a local backup and forget the second cloud service, but it would make it quite resilient to accidental deletes.
That's what I'd do personally, making sure the Synology is protected against drive failure as best as possible.
