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datahoarder
Who are we?
We are digital librarians. Among us are represented the various reasons to keep data -- legal requirements, competitive requirements, uncertainty of permanence of cloud services, distaste for transmitting your data externally (e.g. government or corporate espionage), cultural and familial archivists, internet collapse preppers, and people who do it themselves so they're sure it's done right. Everyone has their reasons for curating the data they have decided to keep (either forever or For A Damn Long Time). Along the way we have sought out like-minded individuals to exchange strategies, war stories, and cautionary tales of failures.
We are one. We are legion. And we're trying really hard not to forget.
-- 5-4-3-2-1-bang from this thread
The amount of data I backup offsite is significantly less than 20 TB. Therefore, my answer to your question will probably not help you.
I store my offsite backups at rsync.net and in one of Hetzners Storage Boxes. For backups in general, I use Borg.
Hetzner Storage Boxes seem much more affordable than AWS, thanks for the suggestion!
However, I would not use the storage boxes as the only backup. The offer has two disadvantages.
The boxes are regularly unavailable for some time due to maintenance work. But these maintenance times are announced in advance.
Hetzner does not specify what kind of RAID is used.
I therefore only use my box as an additional offsite backup and to swap out less important files.