Arq recently reported hundreds of GB of missing files, across multiple backup targets. This is so at odds with Amazon Glacier’s reputed 11-nines durability that I’m guessing it’s due to an application bug. It would not surprise me if the files are still there; Arq just isn’t seeing them. In any event, my strategy is to have multiple cloud backups—Arq and CrashPlan (which has been working very well recently)—so this got me thinking about possibly adding a third.
The obvious choice is Backblaze. It has a native Mac app, is developed by ex-Apple engineers, and sponsors many fine podcasts.
I’d previously been hesitant about Backblaze because of the way it handles external drives. I’ve read about problems with large bzfileids.dat files sucking RAM and preventing backups entirely once they get too large. It’s also worrisome that it only retains deleted files for 30 days—meaning that a file is truly lost if I don’t notice that it’s missing right away. And if, for some reason, my Mac doesn’t back up for 6 months, Backblaze will expunge all my data, even if my subscription is still paid-up. The situations in which my Mac is not able to back up for a while are exactly the ones in which I (or my survivors) would want to be able to depend on a cloud backup!
My other concern is that Backblaze doesn’t actually back up everything. It fails all but one of the Backup Bouncer tests, discarding file permissions, symlinks, Finder flags and locks, creation dates (despite claims), modification date (timezone-shifted), extended attributes (which include Finder tags and the “where from” URL), and Finder comments. Arq, CrashPlan (as of version 3), SuperDuper, and Time Machine all support all of these. Dropbox supports all of them except creation dates, locks, and symlinks.
As a programmer, I especially care about metadata. But I think most users would as well, if they knew to think about it. For example, losing dates can make it harder to find your files (i.e. they disappear from smart folders or sort incorrectly), even leading to errors (i.e. not finding the correct set of invoices for a time period). You would never use a backup app that didn’t remember which folders your files were in, so I don’t know why people consider it acceptable to lose their Finder tags. (If you use EagleFiler, it can restore the tags for you.)
Some people don’t care much about metadata. Macworld’s survey of online backup services didn’t mention it. Neither did Walt Mossberg. (He also told readers that Backblaze automatically includes “every user-created file”; in fact, it skips files over 4 GB by default.) [Update (2014-05-25): The Sweet Setup doesn’t mention metadata, either (via Nick Heer).]
This actually tests disk imaging products, a bad test for backup as items we fail on shouldn’t be backed up by data backup service.
Some people accept this explanation. I think it’s misguided and borderline nonsensical. True, Backup Bouncer tests some rather esoteric features, but Backblaze fails the basic tests, too. It would be one thing to say that there’s a limitation whereby dates, tags, comments, etc. aren’t backed up, but they’re actually saying that these shouldn’t be backed up. As if products that do back them up are in error. So presumably Backblaze doesn’t consider this a bug and won’t be fixing it.
Lastly, it’s a shame that Backblaze isn’t up front about what metadata it supports. Some users are technical enough to investigate these things themselves. Others will have read the excellent Take Control of Backing Up Your Mac and seen its appendixes, which give Backblaze a C for metadata support. But most Backblaze users won’t know that a poor choice has been made for them until they need to restore from their backup.
Stay up-to-date by subscribing to the Comments RSS Feed for this post.