I'm looking to rent a VPS to migrate my data between two cloud drives. The VPS itself is only equipped with a 32GB SSD. Does rclone need a lot of local space to transfer between two cloud drives or can it constantly download, upload and delete chunks without using too much space?
I need to transfer around 2TB of data.
What is your rclone version (output from rclone version )
Which OS you are using and how many bits (eg Windows 7, 64 bit)
Which cloud storage system are you using? (eg Google Drive)
Actually, no data needs to be stored locally even if you are piping all the traffic through your local PC.
Unless you are specifically enabling some sort of caching (which should not be used in this scenario) then any data passing through will only exist briefly in RAM before being sent out again. It is essentially just piped from IN to OUT with a buffer in-between to smooth out the transfer which is good for keeping the utilization close to optimal. (you could disable this buffer too and it would literally just pass from networkcard -> cpu -> networkcard) - although this isn't the best idea in most cases.
Yes, this won't work with server-side sadly - but that doesn't matter so much if you are piping the data through your VPS anyway. As I said, by default nothing needs to be saved to the local storage.
Be aware that many cloud backends have some daily limit to uploads and/or throttling past a certain point. Moving 2TB shouldn't be a big deal at all, but you may have to complete the whole transfer over a few days. I am not very familiar with the spesific limitations that exist on Onedrive as it related to daily upload.