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   How to Relocate a Dropbox Subfolder to Another Disk

   Jeff Carlson

   Since replacing my MacBook Pro's hard drive with a solid state drive
   (SSD), I've enjoyed a wonderful increase in performance that's given
   the aging laptop new life. (See '[1]SSD Optical Drive Replacement
   Speeds a Sluggish MacBook Pro,' 20 July 2012.) The tradeoff of getting
   a much faster drive, though, was dealing with a smaller footprint. I
   downsized from a 500 GB hard drive to a 256 GB SSD as my primary drive,
   but kept the original drive by replacing the computer's optical drive
   (which I haven't needed since).

   Having both drives has made the transition manageable; for example, as
   I describe in the article above, I moved my iTunes library to the 500
   GB disk. But recently I ran into a snag: I wanted to enable
   [2]Dropbox's Camera Upload feature, which automatically copies photos
   from an iPhone, iPad, or a connected camera or memory card to the
   Dropbox folder. The photos are then uploaded to Dropbox's servers,
   giving me an offsite backup of my images I can access from anywhere.

   The problem is that my Dropbox folder is located on the SSD in my Home
   directory. That's where I keep all of my active projects, taking
   advantage of the SSD's speed and, again, Dropbox's capability to store
   backups of my files. This arrangement is no problem when dealing with a
   bunch of articles, but the capacity required for storing photos can be
   immense ' certainly enough to devour the free space on the SSD. I
   wanted to keep the Dropbox folder in place, but move its Camera Uploads
   folder to the more capacious 500 GB drive.

   Dropbox isn't cemented to the Home folder. I can specify that my
   Dropbox folder lives anywhere on my system by opening the Dropbox
   preferences, clicking the Advanced button, and choosing a new
   destination from the Dropbox Location pop-up menu. That applies only to
   the entire Dropbox folder, however. The software doesn't allow
   relocating its subfolders.

   [3][tn_dropbox_relocate_settings.jpg]

   The answer to making it work lies outside Dropbox's options.
   Specifically, I needed Mac OS X to trick Dropbox into thinking it was
   still copying files to its Camera Uploads folder, even if the folder is
   located on another disk. That's possible using symbolic links
   ('symlinks'), which act like aliases in the Finder, but work at a
   deeper level in the operating system. As far as Dropbox knows, the
   folder is still within its hierarchy, which is key to ensuring that the
   images are uploaded to the Dropbox servers.

   I don't spend much time on the command line in Mac OS X, but creating a
   symlink is easy. I followed [4]instructions written by Weldon Dodd at
   GigaOM, who pointed me to the technique after I inquired on Twitter.
   Here's how to do it:
    1. In the Finder, move (not copy) the Camera Uploads folder from the
       Dropbox folder to the destination drive by holding down the Command
       key as you drag it to the destination (in my case, the 500 GB disk,
       which is named WinterXData).
    2. Open the Terminal application (located in
       /Applications/Utilities/).
    3. Type cd ~/Dropbox to change to the Dropbox directory.
    4. Type ln -s, followed by the location of the destination folder. In
       my case, that looks like this: ln -s
       /Volumes/WinterXData/Dropbox_WinterXData/Camera\ Uploads. The
       fastest way to enter the path is to drag the destination folder
       from the Finder onto the Terminal window. Press Return, and Mac OS
       X creates what looks like an aliased Camera Uploads folder within
       the Dropbox folder, but is in fact a symlink.

   With the symlink set up, I then connected my camera and let Dropbox
   copy the contents of its memory card to Camera Uploads. The image files
   themselves appear in the destination folder on my WinterXData volume,
   and copy successfully to Dropbox's servers.

   Should you ever wish to remove the symlink (such as when you get that 1
   TB SSD!), just delete it as you would any other file in the Finder,
   after which you can move the Camera Uploads folder back into place.

   Let me leave you with two thoughts. First, you can do this with any
   other folder in Dropbox as well, should you wish to offload Dropbox
   storage to a larger secondary disk. Second, this symlinking technique
   also works like a charm for moving any other large folder off a small
   SSD to a hard disk. It's best done with folders that hold large amounts
   of data that's not accessed constantly (like your Music folder), since
   you lose the performance benefits of storing that data on the SSD. If
   you're moving one of Mac OS X's default folders from your Home folder
   to another disk, you'll need to authenticate the action with your
   username and password when you move the folder. And, as always, make
   sure you have backups before you do anything major!

   (In addition to Weldon Dodd, thanks to Nik Friedman TeBockhorst and
   Rick Baumhauer for suggesting on Twitter that I try a symlink.)

References

   1. http://tidbits.com/article/13133
   2. http://www.dropbox.com/
   3. http://tidbits.com/resources/2013-05/dropbox_relocate_settings.png
   4. http://gigaom.com/2011/04/27/how-to-create-and-use-symlinks-on-a-mac/

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