Moving terabytes between clouds
A large move is mostly a question of limits you do not control. Here is what they are, and how to plan around them.
What limits the speed
- Not your connection. Files stream between the two providers on our servers, so your home upload speed does not enter into it, and the laptop can be closed.
- The destination's daily cap. Google Drive accepts 750 GB of uploads per user per day, so 2 TB into Drive takes at least three days. Plan it as a daily schedule.
- The providers' rate limits. Every API slows down a client that asks too fast; the transfer backs off and carries on rather than failing.
- Many small files. A million 50 KB files move far slower than one 50 GB file, because each file is several API calls on each side.
Before you start
- Check the destination's largest single file: 250 GB on OneDrive, 350 GB on Dropbox through its API, 5 TB on Google Drive.
- Check what leaving the source costs: AWS bills data transferred out of S3 to the internet, after a small free allowance each month, so a large move out of S3 shows up on your AWS bill as well as on ours.
- Look up your pair in the transfer guides: each says whether files can be checked by checksum on arrival, and what will need renaming.
During and after
- A transfer can be paused and resumed; what had already arrived is not copied again.
- Run the same transfer once more at the end. It copies only what is missing or changed, which is how you know the destination is complete.
Questions
What does moving 2 TB cost?
Transfers draw on a prepaid allowance: 30 GB free, then 500 GB for ₹100 or 2,500 GB for ₹500, each valid a year. 2 TB fits in the 2,500 GB pack. The providers' own charges for data leaving them, where they have any, are separate.
Try it
Prepaid: 30 GB free, then 500 GB for ₹100 or 2,500 GB for ₹500, each valid a year. No card is asked for to start.