Tuesday Tip: Backups (Part 3: Online)

When we discuss backups, we generally advocate primary backups on local drives. However, we sometimes hear, “But, I want to use an online backup!” While, this is indeed possible, here are a few things to bear in mind:

  1. Our sync technology is not a backup, nor is it intended to be. DEVONthink’s sync is not merely copying your database and files to the cloud; it’s transmitting raw, chunked, and optionally encrypted data that is only usable by DEVONthink or DEVONthink To Go 2. You cannot go into the sync location and retrieve a particular file.
  2. You should only use a cloud solution that takes a snapshot and backs up from that. (Time Machine uses this method.) For his online backups, our company president successfully uses Arq, which also uses this method. ​However, most ​backup services ​do not do this​. If a service is claiming ​​”instant syncing” ​or anything that sounds like it’s continuously syncing your data to it, you should consider this as not data-safe. Data could change while the backup is running and you’d end up with a half-baken backup set. If you want to use an online backup service with your DEVONthink database, make sure to research this aspect before committing to it.
  3. Lastly, you should also consider the myth of network persistence, ie. the idea that you always have a network connection up and available, or that remote servers are operating properly. If you only have an online backup but your network is down or you’re in a location with little to no signal, you effectively cut off access to your backups.

As online backups let you backup your data to a remote location unaffected by e.g. a fire in your house or office, they perfectly complement your backup strategy: local drives and a snapshot-based backup application like Time Machine for the fast and activate-and-forget backup and an also snapshot-based online backup service like Arq and the like for the safety net outside our office walls.

11 Responses to “Tuesday Tip: Backups (Part 3: Online)”

  1. Rick Torchia says:

    Is Back Blasé a suitable online backup service for DEVONthink?

  2. Rick Torchia says:

    I also use Carbon Copy Cloner to make a bootable backup of my whole iMac hard drive. My thought is that if my iMac hard drive were to fail that this is the quickest way to get back up to speed again. Meaning, replace hard drive and then put cloned backup on the new drive. What problems do you see with this method. I also have a TimeMachine backup.

  3. Jim Neumann says:

    We can’t comment on all services but this from their Help would not be considered data-safe:

    “Backblaze constantly scans your drive to find new or changed files”.

  4. Jim Neumann says:

    I see no issue with it. Making a bootable clone is “catastrophe insurance”. Time Machine is for general purpose backups.

  5. Rick Torchia says:

    Your article has piqued my curiosity about Arq. It looks very interesting. I reviewed their alternatives for where to store the backup. There are several options, one of which is Wasabi that seems very reasonably priced. You mentioned that the president of DEVONthink uses Arq for his online backup. Would you share what online service he uses and why? Thanks for the great article.

  6. @ Rick Torchia: I’m using Amazon S3 which I also use to store “raw” data like my person data archive. I use S3 as for me it’s a “pure” service that will not go away so soon whereas third-party services are, likely, more comfortable to use but might go out of business eventually. In earlier days I used JungleDisk which became awkward to use after a while. But, S3 might be the more nerdy solution here and there are certainly more user-friendly services out there.

  7. Nuno says:

    Arq looks great, thank you for the tip. This specific feature interests me: “Zero-knowledge backup: Everything is encrypted before it leaves your computer”. Devonthink sync works the same way right? I would love to know more about this topic. Maybe a “devonthink privacy and security best practices” tuesday tip?

  8. @ Nuno: Correct, the DEVONthink sync works the same way. And: Good idea!

  9. Jim Neumann says:


    Everything is encrypted before it leaves your computer

    To be clear about this, your DEVONthink databases are not encrypted in place. The sync data is encrypted on transmission, so the sync data is stored encrypted.

  10. Nuno says:

    @Jim Neumann: so the sync data is protected while in transit from local to cloud storage, correct? I have been reluctant to upload databases with medical history or business documents because I worried about data protection during the upload. All my other devonthink databases are synced and encrypted in a cloud storage through webdav.

  11. Jim Neumann says:

    Correct! The encryption key is used to encrypt the data on transmission, so you end up with encrypted sync data in the sync location (WebDAV, Dropbox, iCloud, etc.).