Server-Side vs Download-and-Reupload: Why the Difference Decides Your Transfer

Server-side direct transfer versus download-and-reupload, explained

Jun 24, 2026

The Two Ways to Move Files Between Clouds

There are two ways to move files from one cloud to another. The common way downloads every file to your computer and uploads it again to the destination, which leaves a full copy on your disk and makes your machine the slow part. A direct transfer streams the data between the two services without staging a full copy on your disk, so local disk space stops being the limit.

The difference is invisible for ten files and decisive for ten thousand. Understanding it saves you from a stalled migration halfway through a terabyte.

Download-and-Reupload, and Where It Breaks

Drag a cloud folder to your desktop and back into another service, or let a sync client mirror it locally, and you are doing a download-and-reupload. It works, and for small jobs it is fine.

It breaks in three ways at scale. First, disk: a 2 TB move needs 2 TB of free space, which most laptops do not have. Second, time: every byte makes two trips through your machine. Third, fragility: a sync client chewing through thousands of files will choke, duplicate, or stall, and you babysit it.

What a Direct Transfer Changes

A direct transfer connects to both services and streams data from the source to the destination without writing a full local copy to disk. The practical wins:

Disk space stops being the limit. You can move far more than your free disk, because the files are not staged there.
It runs in parallel. Many files move at once instead of one slow queue, which is what actually makes a big library finish.
It resumes. A dropped connection picks up where it left off rather than starting over.

The Honest Caveats

A direct transfer is not magic, and it helps to know the real boundaries. The data still travels over the connection of wherever the tool runs, so your bandwidth is part of the equation. Egress, what a source provider charges to read your data out, still applies regardless of the tool, so plan the move as one clean pass rather than repeated pulls. What you avoid is the second full copy on your disk and the double handling that comes with it.

Where Your Data Goes (and Does Not)

There is a second axis worth separating from disk: who handles your data. Some cloud-to-cloud services route your files through their own servers, which means a third party touches them. Blober is a desktop app, so it runs on your machine with your credentials, and your data is not parked on someone else's server in the middle. You get the direct-transfer benefit without handing your files to a relay.

Frequently Asked Questions

What is a server-side or direct transfer? It is moving files from one cloud to another without staging a full copy on your computer's disk. The data streams between the services through the tool rather than being downloaded and then re-uploaded.

Do I have to download files to move them between clouds? Not with a direct-transfer tool. Blober streams between the source and destination without writing a full copy to your disk, so disk space is not the limit.

Why is my cloud-to-cloud transfer so slow? A download-and-reupload sends every byte through your machine twice and often runs one file at a time. A parallel direct transfer keeps many files moving at once, which is far faster for large libraries.

Does a direct transfer avoid egress fees? No. Egress is charged by the source provider for reading your data out, no matter which tool you use. A direct transfer avoids the wasted second trip and the local copy, not the provider's egress.

Get Blober

Move large libraries between clouds without filling your disk. Blober streams files directly between a broad, growing set of cloud providers and local storage, in parallel, and runs on your machine rather than a third-party server.

Download Blober at blober.io