I recently decided to replace the SD card in my Raspberry Pi and reinstall the system. Without any special backups in place, I turned to rsync to duplicate /var/lib/docker with all my containers, including Nextcloud.

Step #1: I mounted an external hard drive to /mnt/temp.

Step #2: I used rsync to copy the data to /mnt/tmp. See the difference?

Step #3: I reformatted the SD card.

Step #4: I realized my mistake.

Moral: no one is immune to their own stupidity 😂