Here, the 2 discs are included and pre-installed, the whole point of the system is to have a turnkey solution, configured in RAID 1 (identical copies on two drives - in this mode, so the system capacity is 2 To model for "4TB"), to avoid losing your data in case of failure of one disk, you can then safely replace.
The physical installation of the system is simple and requires only Ethernet cable (supplied) to connect to the modem router and an electrical transformer. For the software part, that's another story. The included manual is very brief, it is necessary to download the full guide on the manufacturer's website. We can also regret that at this rate, no paper manual is provided, and the neophyte will struggle to navigate.
The system allows you to configure multiple users or groups with rights to read / write which can also be adapted according to the records. Many things are configurable from the web interface, which is quite well done, especially in comparison with other WD older products (My Book Live ...) Specific applications are freely downloadable to use this device remotely from a smartphone (Android or iOS) or laptop for example. One can thus access all the data that you want from any Internet connection, including listening to his music outside the home (Application WD my cloud.) You can also choose to automatically save photos on their phone when shooting. Good point, some defects noted on the applications in question have been fixed (as WD Photos app, which finally allows you to choose the automatic backup directory.)
At home, you can easily use this network drive to store data, share them between computers, or enjoy the DLNA function to directly play audio and video files from the connected TV or tablet, for example. The system has an automatic backup software that will recover important files (although I prefer to organize it myself), it also supports Time Machine (Macintosh.) It is even possible to copy the data to another cloud (this may appeal primarily to SMEs, I think), or to / from an external drive through 2 USB 3.0 ports fitted to the machine, not to mention trade with the most popular cloud services like Dropbox.
Everything runs in an undeniable sound discretion and power saving mode deactivating discs when they are not used. In short, apart from the first hours of operation that need to look at the manual to understand some details (on rights of access to files, for example), it is a quality network drive, I hope reliable (2 mirrored drives in this direction.)
A flat anyway, I happened 3 or 4 times (6 months of use) have difficulty to connect to this drive from the tablet to smartphone and Android application (only from outside , not on the local network.) So it does not happen to me often, but only the restart of the device solved the problem.
Materials tested: PC Windows 7, Windows Mobile 8.1 smartphones android 4.1.2 / 4.4.2 and 4.4.4 tablet, connected TV Samsung, Sony SA-NS 510 with BubbleUPnP.
[*] The manufacturer has recently added new applications that can be downloaded from the control interface, here is a list of applications that you can install:
AcronisTrueImage
aMule
Dropbox
DVBLink
git
IceCast
Joomla
NZBGet
phpBB
phpMyAdmin
plexmediaserver
SqueezeCenter
Transmission
WordPress