Mac on demand sync Workaround (Tested)

Hi everyone, first post here.

I’m currently testing DT and want to share an eureka moment I had, maybe could help someone. I want to one-way sync a huge archive index-only database on my desktop, to a low storage space MBP. But DT currently does not support on-demand downloads on Mac (DTTG does though).

Old 2011 iMac (High Sierra):

  • Main drive 512gb SSD with Dropbox account.
  • External 6000gb spinning HD with an Archive directory (/Volumes/exthd/Archive/) with some big folders (50-250gb each). Folder contents don’t change.

2017 MBP (Big Sur):

  • Main drive 512gb SSD.

MBP: To be able to search Archive directory; and if something is found, download it “on demand”.


  • There is no enough storage space on iMac to put the Archive directory on my Dropbox.
  • There is no enough storage space on MBP to sync full Archive database.


  • Move Dropbox account from the main drive to the external HD; and move the Archive directory to it (/Volumes/exthd/Dropbox/Archive/)
  • Sync Dropbox (took a while)
  • Index each folder of the Archive directory into DT databases
  • Set up Archive directory to “on demand sync” in dropbox
  • Move Dropbox account back to main drive


  • Set up Dropbox account with “on demand” setting
  • Sync Dropbox
  • In terminal:
# sudo mkdir /Volumes/exthd
# sudo ln -s ~/Dropbox /Volumes/exthd/Dropbox
  • Bonjour sync DT Databases


  • Now the DT Databases are indexes that point to Dropbox on-demand files


  • Probably not an elegant solution but worked for me.
  • Any other ideas out there? This solution looks fragile. But gets the job done.



On-Demand Sync on Mac? - DEVONthink - DEVONtechnologies Community


If it’s just an archive and the contents of the archive are indexed & only modified on one computer, then there’s another possibility:

  1. Index the archive on the main computer using a path that is available on all computers (usually a folder in your home directory or its subdirectories)

  2. Create a new sync store and upload the indexed archive

  3. On the other computer(s) add the same sync store but (and that is important!) disable the option to synchronize the contents of indexed documents

  4. Import the archive database from this sync store to the other computer(s)

The search index & metadata are now available on these computers but the files aren’t. However, you can download them on demand, e.g. via the preview pane or via the File menu.

The only limitations are currently that you can modify the files of the archive only on the main computer and that you can’t remove local copies anymore on the other computers after downloading them. Depending on the available space and how often files are downloaded this might be nonetheless an option.


Thank you!

If I understand correctly this means that on the target machine (MBP in my case) I can:

  • Sync the index without document contents, even though the sync location is configured with full sync on the source machine (iMac in my case).
  • When I try to preview content, DT will connect to the sync location and download the file into the indexed path in the target machine

This looks like a proper solution. But in my case, the problem with this approach is that your first bullet does not apply:

Index the archive on the main computer using a path that is available on all computers (usually a folder in your home directory or its subdirectories)

Because the archive does not fit on my source machine’s main HD, and DT does not follow symlinks AFAIK.

Thank you for your thoughts on this!