I'm thinking of using cloud providers for that. Assumptions:

- Data import/export is completely egress (from my local PC)

- Data retrieval time does not matter

Cloud providers offer cheap cold storage:

- AWS S3 Glacier Deep Archive [1]

- GCP Archive [2]

- Azure Archive [3]

Storage seems to be ~1$/Tb/month everywhere.

Retrieval from ~20$/Tb for AWS (not sure about that one - first restore from Glacier Deep Archive to S3 and then Download) [4].

Retrieval for GCP is 51,2$/Tb [5].

Retrieval in Azure is 20,48$/Tb [6].

Questions:

1. Is there a GUI or CLI tool to manage my proposed workflow (infrequent cold backup to one or several cloud providers). I don't want to use their web portals as I'm not a frequent cloud user and all three interfaces are rather confusing and change all the time. Also uploading gigabytes from the browser seems like a bad idea.

2. Is there something better for secure cold backups? At 1$/Tb/month the storage price looks so good. Or am I barking up the wrong tree and there are dedicated backup services with similar pricing?

[1] https://docs.aws.amazon.com/AmazonS3/latest/dev/storage-class-intro.html#sc-glacier

[2] https://cloud.google.com/storage/docs/storage-classes#archive

[3] https://azure.microsoft.com/en-us/services/storage/archive/

[4] https://aws.amazon.com/s3/pricing/

[5] https://cloud.google.com/storage/pricing#archival-pricing

[6] https://azure.microsoft.com/en-us/pricing/details/storage/blobs/