Raspberry Pi 4: Build your own minimalist NAS with ZFS file management

A NAS based on a Raspberry Pi is ready for use in next to no time: A large microSD card or a plugged-in USB drive as data storage, plus OpenMediaVault (OMV, version 4 as an image, version 5 as an installable package) and you can log on to your smartphone or meander through hundreds of menus, dialogs and options in the browser. No question about it, OMV is well-made software and works great – provided everything is configured correctly. However, as soon as a tool, a configuration or a function is not explicitly supported by its web interface, OMV needs manual work. So why not set up a minimalist, tailor-made Raspi NAS with the most necessary functions and a secure file system yourself?

There are several NAS distributions on an open source basis for this. They work, but offer too many superfluous functions even in the enterprise environment. A NAS for home use based on a Raspberry Pi usually requires even fewer functions. Our project is only about storing data in a central location. All that is needed is a handful of services: a secure local file system, a service for sharing in the network and preferably a reliable backup solution.

Choice of file system

Anyone who saves data wants to be able to read it correctly afterwards. This limits the choice of the file system to two candidates. Because only ZFS and btrfs guarantee data integrity thanks to internal checksums. Our choice falls on ZFS, because it runs on the Rapberry Pi 4 with 2, 4 or preferably 8 GB of RAM. With less than 8 GB of RAM, ZFS may not run optimally – you shouldn’t use deduplication.