As the name suggests, Western Digital’s My Cloud appliances are designed for SMBs wanting their own online vault for file sharing, collaboration and workstation backup. The four-bay PR4100 here made its debut back in 2016 but still does a sterling job, powered by a 1.6GHz Intel Pentium N3710 CPU and 4GB of DDR3L memory, which can be upgraded to 16GB. WD also offers the cheaper EX4100, which uses a less powerful ARM-based processor – but we’d recommend it only for lightweight roles as it’s stuck with 2GB of RAM.

While the PR4100 doesn’t support 10GbE, you do get a pair of Gigabit Ethernet ports that can be teamed together, and a pair of power inputs give you a very easy way to add redundancy by spending a few quid on a second external PSU.

You can provide your own drives too, but if you purchase the PR4100 in a diskless state then your two-year warranty covers only the appliance itself. Opt for the 32TB model, which comes populated with four 8TB WD Red hard disks, and not only does the warranty grow to three years, it also expands to cover the media as well as the NAS unit.

Installation is straightforward: we simply had to create a free My Cloud portal account and select the NAS model we wanted to set up. A wizard then ran us through securing the admin account and updating the firmware to the latest version of 5. You can stick with the preinstalled version 3 if you prefer, but if you plan to upgrade then this is the best time to do it, because the process wipes many existing settings and clears out installed apps. 

Although the preinstalled hard disks come set up as a single 24TB RAID5 array, you’re free to change to some other RAID or even JBOD arrangement. Creating your shares only takes a few moments, and each one can be made either public or private, with mobile, web, FTP and NFS access individually enabled.

In use, the appliance presents a simple web console, which opens with an overview of usage, hardware and cloud connection status. A ribbon menu along the top of the window provides quick access to various administrative consoles, plus WD’s app store. This provides a modest menu of 20 apps, covering jobs such as antivirus scanning and remote backup to another My Cloud unit. You can also use the Dropbox app to sync your data with a Dropbox account, or pay $30 a year for WD’s GoodSync service, which lets you sync unlimited data across up to five devices. 

Workstation backup is handled at the client end by a free edition of the Acronis True Image app, which secures user data to WD-branded NAS appliances and USB storage devices. You just need to select what wants backing up (this might be the entire system or just a handful of files and folders), pick the PR4100 as your backup destination and schedule the job to run regularly.

When it comes to performance, the My Cloud PR4100 really couldn’t do much better – unless it had 10Gb Ethernet. Across all of our sequential read and write tests we consistently saw matching read and write speeds of 113MB/sec, indicating that the NAS was fully saturating its Gigabit Ethernet connection. Our backup test using a 10,500 collection of small files was slower, but still completed at a good rate of 83.8MB/sec. 

The PR4100 is a simple appliance that’s getting on for five years old, so it’s no surprise that it doesn’t match up to the latest appliances from Qnap and Synology. Even so, its features and performance are more than strong enough for a small business role, and you can buy it with 32TB of storage for less than many unpopulated rivals. That makes it a worthy choice for SMBs wanting an out-of-the box private cloud solution. 

Western Digital My Cloud Pro Series PR4100 specifications