Dropbox stuck on sync or index

Re: Issue posted by VibDAS DSI

We've been having this exact same issue at our company since December 18-21 of last year. We've been in touch with Dropbox support since the first week of January, and have not been able to solve the problem either.

We're also in a position where we have several machines (in different geographic locations) that are taking in files via Dropbox, processing them, then placing the results back into another Dropbox folder, and in crunch time we have to monitor the machines almost 24*7 to make sure they're still syncing. Sometimes one of our machines will go several days without needing to restart Dropbox, other times we'll have to restart Dropbox multiple times in a single day. It seems to happen more often during high-bandwidth situations. 

Just before the issue started we had reinstalled Windows 2016 Server on our server - which requires a reinstallation of Dropbox on that machine. Within a few days the issues started on most everyone's machine. That timing has been particularly odd & keeps bugging at me, as we had been using this workflow almost seamlessly for over a year - but I never thought until now that something related to Windows Server 2016 itself might be causing the issue - as this is the only Server machine we have. 

I don't think we technically need to have Dropbox on our Server (though it would be nice), so I'm thinking of uninstalling DB from it to see if that fixes anything.

If you do, and it fixes the problem, please post back here.

I'm in the situation right now that our applications have to be run on this server, so our options might be very limited if that turns out to be the problem.

Thank you, Sincerely,

Chris

Definitely. Would appreciate learning anything you discover as well. Thanks!

Absolutely.  Walter is working with me and so I/we will certainly let you know if we find anything.

I'm going to post this here to hopefully benefit all.

You stated "It seems to happen more often during high-bandwidth situations. "

And that reminded me that there was one other "troubleshooting" thing that I did very early on when this first started.

To test our system, and Dropbox.  I had a process that submits one file to be processed every 15 minutes.  When a file is processed it sends out email.  And that same process checks the emails and if there isn't any for 30 minutes it sends an email to let us know things are down.   When this started happening I switched that process to submit the file to be processed in another folder not in Dropbox.  This did help because it was locking up more frequently, like you said sometimes multiple times a day.  Now without that process it only locks up about once a day.  Of course now Dropbox syncing isn't being tested in the flow.  I have to monitor that manually now.

So high-bandwidth might not be the answer as much as "frequency".  Even though 1 file every 15 minutes is hardly "frequent".

By high-bandwidth I was specifically referring to quantity of MB, but for the most part its 1 to 1, as our high frequency moments are often high bandwidth - but there are certain times that larger files than normal are being shared, which almost always causes the issue on one of the machines.

But it doesn't occur on all the machines at the same time - even though they're all syncing the same files ; one machine will stop syncing at time X, and then multiple hours later another machine stop syncing. 

Wow, very strange.  Especially if the server can somehow affect what the other machines are doing, doesn't really seem likely, but who knows?

What this all "feels like" to me is Dropbox is waiting on some locked file, and gets hung up on it.

Even though there isn't a lot of interaction between the program processing the file and Dropbox there is certainly reading the directory about 1 once a minute and if files are in there it checks their modification times to wait for them to be "stable" (two minutes without change) and then copies them out and moves them to a sub directory in Dropbox.

Agreed on the hung-up-on-a-file aspect, but the tricky part is which one? 

The DB tech support staff pointed out a couple files that they noticed were causing issues in ours logs; one of which was definitely problematic, and while its removal did fix one sync issue that we had been experiencing, it didn't fix this specific larger issue. The other files were seemingly quite random, innocuous files that had just been generated.

I'd love to be able to pick through the sync logs myself to see if I can identify any patterns in particular that coincide with any internal/company workflows - i,e, are their certain file types that struggle more than others, certain workstations/users, that sort of thing - but at the moment as users we don't have access to our own sync logs.

I've emailed the staff to see if they can send us copies of the logs for one particular machine that experienced the issue on two specific days; hopefully that will help us track down the issue.

Are you still getting this problem?

About 3 days ago Dropbox updated to 116.4.368, and so far our Dropbox hasn't hung up on the sync.

I even changed back to the system where I put in a file to be processed every 15 minutes, which caused it to hang up more often, and so far (one day) it has hung up.

Note that Walter did get back to me and tell me since the server operating system isn't supported they couldn't look into it further.

Hopefully you/we get lucky.

Not sure; over the past couple months we went through a week or so where the issue didn't occur because we weren't stressing the system; if we can go several weeks without it happening, or proceed through a few high bandwith timeframes where it doesn't occur, then I'll be able to more confidently say it's fixed.

That said - yesterday we discovered another potential cause of the issue - a (very) hidden system file that Windows 10 generates inside our Dropbox due to the fact that we're mounting one of our Dropbox folders as a system drive letter. The file ("System Volume Information") has several layers of heavy permissions protections, so DB tries to sync it but can't - and that might be causing the hangups. If we bypass the permissions and delete the file, Windows will eventually replace it. If we bypass the permissions and let it sync, then we get some 'Conflicted Copy' bugs. 

At the moment the file is deleted on those machines... so if we have success in the short run, it might be because of that, or it might be because of the Dropbox update... only time will tell.