A Word About Backups

Internal Backups

DEVONthink does not do file backups. That is the job of backup applications, as we discuss next. However, for your databases, it keeps an internal backup of each one's internal metadata. This is a rolling weekly backup, maintaining two internal backups inside the database package. These are only used for troubleshooting in very specific circumstances.

File Backups

When it comes to backups, there are a few critical things to consider:

• Do not put your databases in the cloud: This may seem like an obvious thing to do, but you should never put your DEVONthink databases in any cloud-synced location, e.g., iCloud Drive, or you could irreparably damage them.
• Sync is not a backup: As noted in our FAQ, sync is not a backup, neither advertised nor advocated as such. While database restoration may be possible with sync data, it is not meant to be relied upon or used in lieu of proper primary backups. Backups should be application-agnostic; sync is not. And backups preserve previous versions to restore; sync does not. So you can't recover files from the past.
• Snapshot-style backups: When considering backup applications or online backup services, you should not use a feature that claims continual or "real-time" backups. Instead, you want to use a snapshot-style backup that backs up the machine on a schedule, at a particular point in time.

Backup Options: Concerning how and where to create your backups, there are several options to consider. Generally, we do suggest having a local backup as your primary as it's the quickest and easiest to access, unaffected by network conditions or online services.

• Local: Backing up your files is simply done and often only requires connecting a hard drive. Apple's Time Machine or similar application like Carbon Copy Cloner and an external drive makes backups as simple as connecting an external hard drive, giving Time Machine permission to use it, then letting it do its thing. And with the low cost of portable external drives, it's even feasible to take a multi-terabyte drive, small enough to fit in your shirt pocket, for backups when you're out and about.
• Time Machine Snapshots: Other than being free, already installed, and very simple to use, another benefit of using Time Machine is local snapshots. If you have backed up your Mac with it just one time, Time Machine will create local snapshots of the internal drive even if your backup drive isn't connected. This happens once per hour, keeping each snapshot for 24 hours. While it may not allow you to recover something from a month ago, it can certainly help you restore something within the last hour or day. So regardless if you ultimately end up using another backup application, we strongly recommend doing a full backup with Time Machine, especially when you're first setting up a new machine.
• Backup Archive: Specific in DEVONthink, another available backup option is creating an optimized and compressed copy of the whole database that you can then save on a server or other media. Use File > Export > Database Archive or Scripts > Export > Daily Backup Archive to create a ZIP file of the database. The former option allows you to choose a folder to save to; the latter uses a Backup folder in your home folder.
• Local Networked Volumes: It may be possible to do a backup on a file server (NAS) on a network. This may be done via a backup application supporting backups to remote volumes or possibly backup software provided by the NAS manufacturer. In either case, you should again ensure it's using a scheduled snapshot, not continuous backups. Also, some routers allow you to connect an external hard drive. This too may be used for backups. Bear in mind, backup performance to a networked volume of any kind will be better when your Mac is connected via Ethernet.
• Online: Backing up your data to the cloud is also possible, either as an alternative or a secondary backup. Arq Backup is well known to work well with DEVONthink's databases. Check the support pages for a service to see if it uses scheduled backups.
• Offsite: Considering the potential for unforeseen events, like fires, earthquakes, tornadoes, etc., having an off-site backup is widely considered an important part of a full backup strategy. A full backup can be performed periodically and stored at a secure, off-site location such as a bank safe. You can also put database archive ZIP files of your database in your cloud account to provide another online backup.

Redundant Backups: There is a common method of backing up files, known simply as the "3-2-1 backup". This means: 3 copies of a file, on 2 separate types of media, with 1 backup offsite. Of the three copies, one is the working copy, in DEVONthink, this is the database you're working on. The other two copies are backups. Of the two media types, one is typically an external hard drive. The second could be another external hard drive, an online backup, or even specialized media like a tape drive used in corporate situations. And ideally, you should have at least one offsite backup as previously mentioned. While using this method isn't a requirement, it may be something you want to consider.

Test Your Backups: Lastly, and something many people don't consider: you should periodically test your backups. Anything in life can fail at some point, so yes it is possible to have a bad backup. Generally, it's not something to be overly concerned about. However, every 4 to 6 months, you could restore a database to a separate location and open it. DEVONthink verifies a database when opening it and reports if there is anything wrong. If all is well, delete it and repeat with other databases, if desired. If there is an issue, close and delete the restored copy. Then do a File > Verify & Repair Database on the current database in DEVONthink to ensure it's healthy, fix things up if it's not, then initiate a manual backup. You may want to add a calendar event or even in the Comment in the database's Database Properties, noting the date of the verified backup.