Why does sync upload start over if previous was cancelled?

If I sync a new database for the first time, and its a large database, I have to wait for all the files to upload of course. If I cancel this at the very last minute, for some reason (internet drops out, I have to leave) then why does this reupload all files it already uploaded next time I restart the sync?

Can it not know what files were already uploaded if the sync was cancelled early? I have large databases and its a nightmare trying to upload them to the sync store, I have to make sure I am online for a long time and not using the internet (so in effect I can only do an initial upload at night instead of in stages in the day).

I had to cancel a sync right at the last minute earlier, after 2 hours of uploading. When I synced again it started all over!


It should (and does, as far as I know) resume transactions that are cancelled or failed. In fact, one of the bugs in 2.7/2.7.1 can only be caused by resuming a transaction, so I’m fairly sure this is working. If it’s not, please open a support ticket.

This doesn’t work, though, if you start a transaction on your machine at work, cancel it (or encounter an error), and then start a new transaction from your home machine – the home machine doesn’t know about the work machine’s transaction and can’t resume it.

Sync 2 doesn’t have this concept – or, rather, each transaction is just one record long – so this problem won’t exist.

No it resumes all over again. I have done this several times.

I am syncing a database with a webdav server on an Amazon EC2 instance I have.

I am specifically talking about if I click the cross on the right of the sync status to close this down before it completes.

P.S. This close button often results in new sync’s not working. I have to close DT and re-open in order to start syncing again, after everytime I use the cross to stop a sync process.

My question is: Why do you cancel Syncs so often? :question: Is this just during testing?

There are a few situations when I may need to cancel a sync…

  1. I am moving my sync stores to an Amazon EC2 instance, as per another thread there may be issues on my office Webdav, I’ll try the EC2. One DB is 1.2Gb and I have a very slow broadband upload. I would like to start it when I know I am leaving the office or something, then pause/interrupt when I get back, and then resume later. But it does not resume! It starts again. I have to remember to start it this evening before I go to bed. I have forgotten the past two nights so all this time I am losing without a working sync store.

  2. During normal operation if its mid sync and I need to turn the computer off/restart for some reason but its a big file and will take ages to sync, I need to cancel it and resume later

  3. Testing as you say, I have issues as per another thread so am trying syncing often and I notice it starts again each time (even when I have not cleaned the sync store) rather than resumes.

Changes to the database can invalidate the older transaction, due to Sync 1’s design (another grain of sand on the beach of reasons I’m rewriting it from the ground up). So syncing, stopping the sync, making changes, and then resuming the sync will not work. In general, there’s no reason to stop the sync while you’re working anyway, since any record modified during the sync that would’ve been modified at the end will be skipped and become a conflict for the next sync.

I dont think I made any changes. I cancel a transaction, then later start the sync again, nothing changed in my files. I shall try again later, as I am still testing a lot due to moving sync locations.

I am also experiencing this problem, not of my choice, but due to internet dropouts. It is becoming very tiresome to have to recommence from the beginning large syncs after they have been running all night, if they get cancelled for some reason at the last minute…back to square one!

Is there any solution?

I would consider whether Dropbox is the appropriate choice for the Sync location. Many times, people find it is not. (And the answer isn’t yes, just because you have a Dropbox account. :smiley: )

Thanks — yes perhaps you are right. I will try just syncing between my machines on my home network, although I won’t be able to sync while on the road as I’d hoped.

Many thanks, this is clearer now.