Migrate from google drive to dropbox without service interruption

[Emmer]

I'm attempting to use the help and support template for this forum however i do not have a problem with rclone at all, in fact i've been using it without issue for many years.

I do seek some knowledge and understanding before embarking on quite a massive migration from gdrive to dropbox (~300TB)

In other topics i've noticed people speaking about mergefs and that it would be possible to do rclone move instead of sync or copy without services being interupted, in my case that would be plex.
Did i understand correctly that it is possible to have 2 remotes on the same "mountpoint" (i'm unsure if that's the correct name for this) and in the background data would be moved from one to the other and nothing would be interrupted (within reason of course, i understand that a currently playing movie would not work)

my apologies for steering away slightly from the template, i'm looking for some help and the logic of this endeavor before i start. Any help on how to achieve this magical feat would be greatly appreciated.

Or if i've misunderstood and this is not possible that would also help me greatly, thank you very much.

[kapitainsky]

Let's say you have two remotes gdrive: and dropbox:

Create union remote:

[union] 
type = union
upstreams = gdrive::ro dropbox:

mount it and point plex to it.

You can upload any new content to this union. It will be saved in dropbox: as google one is read only (:ro).

For migration itself keep moving stuff from google to dropbox. Regardless where content is it will be visible in union.

[Emmer]

Wow that easy? That sounds absolutely wonderful, once i get the go-ahead from dropbox about the initial bulk i will give that a go.

thank you very very much indeed