How Snapshots Saved My Time Machine Backups
Until last year I kept my Time Machine backups on a USB drive next to my computer. And although everything worked fine, I didn’t feel comfortable with so much data stored on a single disk. Hence, during summer 2020, I bought myself a DiskStation DS1520+ to put my Time Machine backups on a much more secure and reliable solution. The DS1520+ supports a RAID. Consequently, my data would not be lost caused by a single disk error. Synology has excellent documentation, how you can enable Time Machine backups to a NAS over SMB.
And everything ran very smoothly until I upgraded to macOS Monterey. Afterward, the Time Machine backups gave me some headaches. Quite often, macOS told me it can’t perform any new backup. The error message was:
This wasn’t an issue with the hard disks; the disks were ok. But for some reason, the Time Machine Backups went corrupt. Fortunately, I remembered that I enabled Btrfs snapshots for most folders on my NAS. This allowed me to go back to a time when the Time Machine backup was still ok. In the end, I only lost the incremental backups of a single day.
Btrfs snapshots are a life-saver. I have snapshots enabled for all my shared folders, which contain important files. e.g.
- Personal Files
- Time Machine Backups
Snapshots are quick to take, easy to restore, and pretty lightweight. For my 1,800 GB Time Machine backups, I have snapshots of less than 40 GB. (~2.2 %). And that is why you should enable them as soon as possible for your valuable files.
Enabling Btrfs Snapshots
- Open the Synology Disk Station Manager, and check in the Package Center under Installed that the package Snapshot Replication is available. Please install this package before proceeding.
- Open Snapshot Replication, select Snapshots and the Shared Folder you want to configure the snapshots for.
- Select Settings and configure the settings for schedule, retention, and advanced.
- Click OK to complete the configuration.
Restoring from a Btrfs Snapshot
- Open Snapshot Replication, select Recovery and the Shared Folder you want to restore.
- Open Recover and select a snapshot when everything is ok. The more recent the snapshot, the smaller the data loss.
- Open the menu Action and select Restore to this Snapshot.
- In the dialog select, Take a snapshot before restoring to create a snapshot of the current hard disk so that you can always restore to a point in time before the recovery takes place.