The Raspberry Pi is a low cost small footprint computer running Debian Linux. It’s primary use is educational however it is also widely used in all sorts of projects and embraced by the geeks of this world.
The specs are moderate in the sense of modern computing but so is the power consumption, use of an embedded device that runs on battery or use it as a server 24/7. Measured power consumption is approx 3 watt, and no moving parts so no operating noise. Server use was the first project I completed. You should be aware that it is good to have some Linux knowledge. You will not use a GUI especially when used as a server, it will run in the so called headless mode. Great help is available through the forums and it you make a mess it is easy to flash the SD card that contains the operating system. Basic file functions are very easy to implement, in my case I have a 2 TB disk connected through USB that contains the whole of our digital archive and is accessed throughout our local network and some parts through remote connections. The archive contains pictures, music, movies and some documents. File protection locally is user based using unix conventions. Pictures are shared to the outside world through the griepsite.nl website, to show the pictures JAlbum is used. For music I use the Logitech Mediaserver that serves connects to the alarm clock and on each windows PC through Squeezeplay. To listen to music outside home the Logitech port is forwarded.on the router. Documents are shared to the outside using https, Samba, nextcloud and WEBDAV. To enable HTTPS a certificate is created through let’sencrypt. The webserver is Apache2
This configuration is completely stable and running for a couple of years. It provides functionality that any commercial available NAS will provide not only at a lower cost but also configured to your needs.
The 2 TB disk is connected through USB to an external cabinet which has no fan and is completely quiet. The whole unit located in the space between the walls. The network adapter supports 100mb only so there is no need to upgrade the rest of the network. Large file transfers are fine (10mb/sec max), streaming of music and movies is never a problem. The USB connector supports version 2. I use a Raspberry Pi 3 to accomplish this, the system is stored in the cavity wall near the router from the internet provider, I use one of the router ports for the network.