This is my second one of these, and they work quite well. The first one lasted eight years. The only thing I would caution with is that the unit has a factory default IP address. If your router has a range of valid IP addresses, and the NSLU2's fixed IP is outside of that range, it will not see it or allow you to connect. You first have to modify your router to include it, then in the unit's setup change the fixed IP address option, and let your router assign one.
This is an outdated product no longer supported by the manufacturer. To use a hard drive it must be formatted with a proprietary format? While my Linux based network had no problem withe the drives connected to the network my windows users could not connect or lost connections keeping me very busy. I just took it off the network.
This Network Attached Storage (NAS) device is OK as far as it goes. It was pulled out of production in 2008, so the technology is restricted. It only supports what are now relatively small USB external hard disks (300G to maybe 500G). I didn't know that before purchasing. I ended up giving it away and purchasing a new product that supports a 4T drive for my home network backup system.