Which setup with data on Btrfs USB-HDD plus backup USB-HDD?



Hello all,

I’ve been working on a productive install of Nextcloud on my RaspberryPi 3 for a while, testing the NextcloudPi image and using the docker image on a Raspbian image. I want to use an external USB-HDD for the data dir (ideally also database) and use Btrfs as the “file system” for it (reason: Snapshots as backup with minimal disk space usage). The backup files should then be copied onto a second USB-HDD (if this is Btrfs formatted or not isn’t important to me, but I don’t know enough about Btrfs yet to decide if it’s actually necessary or not).

Which system is better to use for this? With the full NCP image everything is easier (if it’s possible to do with the limited NCP toolset), but using Raspbian with the NCP docker container means less NCP-tools that I can use due to the sandbox modell of docker.

What should I do for the easiest setup that gives me a great backup system and easy upgradeabilty?

Thank you for any tipps!


You are right. Due to docker isolation it is harder or even not convenient to bring some of the SD card version features. The SD card version will be more easy/powerful in this regard, while the docker version is more flexible and easy to install in different systems.

You can now use any external directory as your persistent volume for the docker version, so your datadir and database could be in a external BTRFS filesystem, but you would have to implement the snaphsot and snapshot sync functionality externally to the docker container. This might help


Thanks! Your blog post was the starting point of my idea to use Btrfs in the first place. :slight_smile:

If I use the SD card version, can I configure the external drive or do I have to setup the snapshots / volumes with a full linux system first (i.e. Raspbian or a live DVD or something)?


The SD card version is able of formatting your drive to BTRFS ( you will lose all your data there ), and automatically creating / synchronizing snapshots