Pushing Dropbox limits on external drives
Six Colors subscriber Lindsay writes:
I use Dropbox for storing all my work and personal files and syncing between my three Macs. The plan was to move my Dropbox folder and my Apple Photo Library to the external SSD, leaving the internal SSD mainly for Applications. The issue I am having is that Dropbox re-indexes every time I restart the Mac, taking about 6–7 hours, then syncs for another 4–5 hours.
Lindsay wonders why Dropbox doesn’t work correctly on a non-startup volume, a feature that Dropbox supports.
Containment breached
Dropbox offers step-by-step instructions for relocating its folder from your startup volume to another volume, whether on the same drive or an external drive. Those details are straightforward. But I’m more interested in the requirements before you move the folder:
- Your Mac has to be running macOS Catalina version 10.5.4 or later.
- The volume has to be formatted as APFS (Apple Filing System), the filesystem Apple transitioned macOS to several releases ago.
- The volume must be encrypted.
- Finally, you can’t have more than 500,000 files in your Dropbox folder.
The first requirement is easy enough—just check About This Mac in the Apple menu.
Use Disk Utility (Applications > Utilities > Disk Utility) to examine the drive. With a volume selected in the sidebar (View > Show Sidebar), the main Disk Utility window displays information, including the formatting type. It will appear as APFS Volume if formatted as APFS. If not, consider converting to APFS—there’s typically little reason to keep a volume as another format unless you have a historical purpose for it. Control/right-click the volume in the sidebar and choose Convert to APFS. (This operation is non-destructive, but be sure you have a backup beforehand.)
Encryption isn’t shown in this main view. You can either:
- Click the info (i) button with the volume selected and look for the “File system” entry, which should read “APFS (Encrypted).” There is also an “Is encrypted” item: a Yes or No indicates the status.
- Control/right-click the volume on the Desktop. If it’s encrypted, the menu shows Decrypt as an item. If it’s not encrypted, then Encrypt appears.
If you haven’t yet enabled encryption, the easiest way is through that Finder menu. Make sure to generate and store the volume password in a password manager, as it will otherwise be unrecoverable if you can’t recall it later.
The maximum file limit can be checked in the Finder. Because of how Apple moved cloud-based storage services into a separate hierarchy, you can no longer directly select the Dropbox folder and then choose File > Get Info. Instead, click the Dropbox folder in the Finder sidebar or click the Dropbox menu icon and click the folder icon to open Dropbox in the Finder. Now, with no folders selected within the window, choose File > Get Info.
Lindsay thinks the file limit was the missing problem. Unfortunately, while Dropbox has that limitation, the company doesn’t explain why, nor does it present an error message via its app, a notification, or other methods when you have too many files for a volume other than the startup one to work.
Making sense of storage
For more help in making sense of managing storage on your Apple devices, you might consult Jeff Carlson’s Take Control of Your Digital Storage. The book examines all kinds of attached, network, and cloud storage as well as encryption, choosing filesystem types, and troubleshooting.
[Got a question for the column? You can email glenn@sixcolors.com or use /glenn in our subscriber-only Discord community.]
[Glenn Fleishman is a printing and comics historian, Jeopardy champion, and serial Kickstarterer. His latest books are Six Centuries of Type & Printing (Aperiodical LLC) and How Comics Are Made (Andrews McMeel Publishing).]
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