Client just deleted 500GB + of files for no reason

[Vantage-DS]

Server - 13
Ubuntu 18 LTS

Laptop Client - 2.3.3
Windows 10 Pro

Also on network -
Mac Client 2.5 Daily
High Sierra

Expected behaviour

The 2 clients sync chosen folders with the server. Any changes are synced between the 3 computers.

Actual behaviour

With no warning, the Windows 10 client deleted over 500GB of files and folders. No reason, no pattern. It just left 3 folders behind.
The Mac client and the Server have not been affected luckily. My data is still intact on the server and mac.
The Windows 10 client thinks it's fine and has a green tick assuming its synced and up to date, but it's obviously not.

Steps to reproduce

1. Unknown. The client has been fine for days. Nothing was changed on the server or any client.

[camilasan]

Hi! Could you provide the client logs? Is there any reason for you to no update the server to 14?

[Vantage-DS]

I'm not at my home computer now but will get logs. Is there anyway other than pressing F12 in the client to get logs because as far as I'm aware this only starts logging after you've pressed F12?

As far as updating, my server only informed me of an update from 13.0.1 > 13.0.6. Now I've just clicked that update its offering 14. Is it ok to do this now without losing the logs you need?

Thanks

[camilasan]

If there are any client logs you may find it at C:\Users[username]\AppData\Local\Nextcloud. As for the server logs, I would copy it before updating.

[Vantage-DS]

There are no logs there unfortunately.

All i have is a screenshot of a list of files being deleted from the client but that's not going to be any help.

I don't think there's anything I can do to give you any info to why this happened is there?

[camilasan]

Could you try to describe what happened when the client 'decided' to delete your files? Did you update your Windows? Reboot? Renamed or moved files? Etc?

[cluxter]

I posted in #289 (comment) about the same issue. Linux and MacOS are also affected.

[cluxter]

@camilasan In my case, all I did was waiting. Nothing else. Sometimes for a long time, sometimes for a short time. It's totally random, it can happen anytime on any data and on any platform (see my link in previous comment). This should be tagged as Critical right now.

[camilasan]

I posted in #289 (comment) about the same issue. Linux and MacOS are also affected.

#289 (comment)

In short: try the 2.5 version of our client (https://download.nextcloud.com/desktop/prereleases/)

[juliusknorr]

Also please provide sync logs, if the error happens again.

You can find those in the following locations (for 2.5):

Linux:
~/.local/share/Nextcloud/[SyncedFoldName]_sync.log

macOS:
~/Library/Application Support/Nextcloud/[SyncedFoldName]_sync.log

Windows:
C:/Users//AppData/Roaming/Nextcloud/[SyncedFoldName]_sync.log

[cluxter]

Thanks for your answers.

I'm still trying to reproduce this critical bug in order to get the relevant logs.

Sorry but trying v2.5 of the client is not a proper solution until we are able to reproduce this bug. We need to clearly identify the source of this bug if we want to be sure that it's gone. As long as you can't tell what caused this critical erroneous behaviour (again: losing data is critical), you must assume that it's still there. Software engineering is not an experimental science, it's an exact science and it should be treated accordingly.

[Vantage-DS]

I wouldn't even know what to do to reproduce it either.
When it happend I was working on the Mac editing video and then some photos, after everything had saved I went to my windows laptop to check it had all synced and that's when I saw everything had been deleted.

It's not happened since and the only big change I've made is disabling the Adobe premiere cache folder from being synced (pointless anyway). Its impossible for me to know whether this has anything to do with it.

[cluxter]

@Vantage-DS Do you have the option "Synchronize hidden files" enabled in the client on the computer which lost your data? And what about the other one?

[rwat1]

I HAVE THE SAME PROBLEM, OMG I NEED TO REDOWNLOAD 500GB over my terrible internet connection. This is horrendous, how can this be happening? Is this a Beta release, why did I upgrade?

[Vantage-DS]

This reminds me of another issue I had with bitlocker recently - #3315
With that problem, files didn't delete themselves, but the Nextcloud client decided at random it would start syncing files I didn't want it too if the Nextcloud client was open before I'd unlocked my drive.
Much like #703 but in reverse /shrug

[mgallien]

@Vantage-DS Can you test with the latest version ?
If you cannot reproduce, can you close the issue ?

In any case, to be able to work we need the desktop client logs as indicated before.