• $SNAP_DATA (/var/snap/nextcloud/current/ by default)
  • Logs (Apache, PHP, MySQL, Redis, and Nextcloud logs)
  • Keys and certificates
  • MySQL database
  • Redis database
  • Nextcloud config
  • Any Nextcloud apps installed by the user
• $SNAP_COMMON (/var/snap/nextcloud/common/ by default)
  • Nextcloud data

Snap confinement is an Ubuntu security feature. This is the reason Nextcloud snap is not supported on non-Ubuntu distributions. So unless you allow the Nextcloud snap to access removable media in /mnt or /media you will not be able to access any other directory outside of the confinement on Ubuntu.

Removable media must be mounted to either /media or /mnt as root with root permissions and connected to Snap!

The interface providing the ability to access removable media is not automatically connected upon install, so if you'd like to use external storage (or otherwise use a device in /media or /mnt for data), you need to give the snap permission to access removable media by connecting that interface:

sudo snap connect nextcloud:removable-media