Terastation TS5800DN

Stock Firmware Installation
Buffalo provides a disk image and instructions to create a USB recovery disk (see support link at the bottom of the page). To re-install the firmware simply boot from that recovery disk and then use the firmware updater in debug mode to install the firmware. see: Enable Debug mode for LSUpdater/TSUpdater

If for some reason you don't want to use Buffalo's recovery disk (or they stop hosting it) you can create your own. see: Create Recovery Disk for Intel-based Terastation

Custom Firmware/Operating System installation
These devices run on an Intel Atom processor with a fairly typical BIOS and include a VGA out and support USB keyboards, you should be able to run virtually any operating system that will run on a normal PC depending on drivers/etc.

For tools to help install and configure Debian on these devices, see Installing Debian on Intel Terastations

Device Notes
The front USB 3.0 port is attached to the main board by a cable which is glued in place. It is very difficult to remove without breaking the port.

Buffalo Resources

 * Buffalo Support
 * Manuals, Firmware, etc