First sync - will it upload local files that already match what's on OneDrive from previous syncing software?

[rc-a1x3]

Hi
My first day trying out OneDrive for Linux (Raspberry PI OS) as a possibility.

My home network has an old, unsupported NAS (Netgear ReadyNAS) which unfortunately recently stopped being able to do its native syncing with OneDrive. It is used as the "source of truth" in our household network with OneDrive just for convenient, away-from-home access. There's about 200GB / 65000 files in total previously sync'd from the NAS to OneDrive.

On my linux box I have successfully mounted (CIFS) 4x mount points corresponding to folders on the NAS which have matching folders on OneDrive. e.g Linux mount locations:
/media/user1/NAS/OneDrive/Pictures
/media/user1/NAS/OneDrive/SharedDocs

When I open Microsoft OneDrive on a browser, under "My Files" I have the matching "SharedDocs", "Pictures" and the other two folders at the root level.

My setting for:
sync_dir = "/media/user1/NAS/OneDrive/"
local_first = "true"

I have been working my way through the usage documents and doing numerous dry runs.
I have configured the .nosync files and nomount settings (very handy!)
I've set the http/1.1, ip protocol 1, excluded directories .. and the dry runs seem happy with their interaction with OneDrive.

I have worked my way up to the full "onedrive --sync --resync --dry-run --verbose" with the 4x target folders.

My questions are, before I do my first non dry run:

(1) It looks like every file and folder identified on my local shares is getting a message like:
"The file we are attempting to upload as a new file already exists on Microsoft OneDrive: ./Pictures/Holidays/Japan/P1010218.JPG"
That is, it seems to recognise what files to sync and where to match them on OneDrive, but what I'm not sure of is whether this will lead to an upload if this wasn't a dry run? Or does this message mean it would see the OneDrive file and not overwrite it with the same file?? I don't have a good enough network to upload 200GB if I can avoid it (i.e. several days uploading!)

(2) The dry run, resync (with verbose logging) is taking several hours to execute even though it's not transferring any files. Is this an indication of how long a normal sync will take, or is it just the resync overhead?

Thanks for any helpful advice,
Ross

[abraunegg]

@rc-a1x3

Using --dry-run is a good indicator of what is going to happen.

99.99% of the time - if the file online matches in hash and size what is local, the file will not be uploaded / replaced online.

The Microsoft Graph API does do some funny stuff however at times, including modifying your file post upload, so there may be subtle differences that will be detected.

The time taken is due to most likely you using local fist as your option - as each individual file needs to be checked and validated if not in the database.

Compare with dry run and not using local first.

Please ensure you are using v2.5.10 as your client.

[rc-a1x3]

Thank you

…

________________________________ From: abraunegg ***@***.***> Sent: Sunday, February 15, 2026 7:31 PM To: abraunegg/onedrive ***@***.***> Cc: rc-a1x3 ***@***.***>; Mention ***@***.***> Subject: Re: [abraunegg/onedrive] First sync - will it upload local files that already match what's on OneDrive from previous syncing software? (Discussion #3642) @rc-a1x3<https://github.com/rc-a1x3> Using --dry-run is a good indicator of what is going to happen. 99.99% of the time - if the file online matches in hash and size what is local, the file will not be uploaded / replaced online. The Microsoft Graph API does do some funny stuff however at times, including modifying your file post upload, so there may be subtle differences that will be detected. The time taken is due to most likely you using local fist as your option - as each individual file needs to be checked and validated if not in the database. Compare with dry run and not using local first. Please ensure you are using v2.5.10 as your client. — Reply to this email directly, view it on GitHub<#3642 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/BOURKWII4V36PJFBH5NKURL4MAVHLAVCNFSM6AAAAACVFV3ZNSVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTKOBQHE4DAMY>. You are receiving this because you were mentioned.Message ID: ***@***.***>