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Western Digital MyCloud Expert EX4100 Review

Brian Nadel

Long known for its dependable hard drives, external storage and RAID arrays, Western Digital lowers the cost of entry to fault-tolerant data storage with its MyCloud Expert EX4100. By putting the emphasis on packing power and features into a small and inexpensive RAID array, the EX4100 holds four drives and can make data failsafe while fully encrypting your business's data. At $350 on its own or $700 with 8TB of storage space, the EX4100 is a winner by providing small companies reliable storage on a tight budget. 

Western Digital MyCloud Expert EX4100

Western Digital MyCloud Expert EX4100

The Verdict

A great choice for small businesses that aren't data heavy, the Western Digital MyCloud Expert EX4100 is inexpensive, can encrypt a company's worth of data and rebuild lost data. It is a perfect choice for a small business RAID array.

View all of our recommendations for RAID Recovery Services on our best picks page. 


Built around a black steel case, the four-drive MyCloud Expert EX4100 is roughly the size of several books at 7.6 x 6.7 x 9.1 inches. It's smaller than the Synology DiskStation DS1019+, which can hold five, not four drives. 

Its stand-alone design means you don't need a server rack, and the unit can sit on a desk, shelf or even the floor. The prominent power button is augmented by blue activity LEDs under the drives and a two-line blue monochrome information screen. It displays the system's essentials: IP address, firmware, drive temperatures, fan speed, remaining capacity and whether the drive is healthy or not. There's a big cooling fan in the back. 

Inside, the EX4100 has a 1.6GHz Marvell Armada dual-core processor, 2GB of RAM and a megabyte of cache. On the downside, none of this can be changed or upgraded, although the company sells a slightly more expensive PR4100 model that is powered by a 1.6GHz Intel Pentium N3710 Quad-Core processor and 4GB of memory. 

Behind the scenes, both models feature redundant power inputs, although you'll have to buy a second $40 external power supply to get its benefits. The EX4100 does without anything like the battery backup on Drobo's 5N2, which allows the unit to finish its writes in a power failure. 

As is the case with many of its competitors, the EX4100 has two Ethernet connectors. This allows it to operate on a standard gigabit network with redundancy or by using port aggregation to double its peak throughput. Its pair of USB 3 ports in the back and one upfront allow the device to work as a local and networked drive array. On the downside, it lacks the high-speed Thunderbolt port that's provided on the QNAP TVS-1282T3 array. 

The array holds up to four 3.5-inch SATA drives but lacks a fifth slot for a hot spare. The drives easily slide into the case without any carriers or mounting hardware. There's a secure door to ensure the drive connectors stay seated. It's quick to change a drive and snap it into place. 

Internally, the EX4100 uses the reliable Linux-based EXT4 file system, and can work with inputs that use FAT, NTFS and HFS+. The EX4100 is a versatile performer on a business network with the ability to use Active Directory services on a Windows Server 2003, 2008 and 2012 system. It can operate as a DHCP client that automatically gets its IP address from a server or with static IP addressing and can be set up as an NTP Client with Dynamic DNS (DDNS), an 802.1Q VLAN, Link Layer Topology Discovery Protocol, iSCSI and an SSH file system. 

Fully populated, the EX4100 can hold up to four 8TB drives for a total raw capacity of 32TB, although using one of RAID's more failsafe modes will diminish this considerably. On top of supporting the JBOD (just a bunch of drives) standard, it can store data using RAID levels 0, 1, 5, and 10 for a variety of capacities, speed, and data reliability profiles. If you use RAID 1, 5 or 10, the array's controller can rebuild a lost drive. 

On the other hand, for rapidly growing companies, the EX4100 comes up short on expansion potential. It can neither use the Drobo 5N2's ability to daisy chain several units or Synology DiskStation DS1019+'s separate expansion unit that can hold an extra 10 drives. 


The EX4100 is moderately secure with password protection. It can use its hardware to encrypt an entire drive or selected key files using AES-256 encryption. On the downside, encrypting and decrypting data can take a toll on the drive's performance. 

Although the EX4100 keeps track of its operations in detailed logs that can be investigated in the case of a failure, it can't track individual users and what data they have accessed, deleted, or changed. It does without the drive bay lock of Buffalo's Terastation 3410DN, and the only physical security it offers is a Kensington lock. 

Like other Western Digital MyCloud devices, the EX4100 can be set up so that those with the right credentials can access the array's contents from anywhere they can get online over an encrypted portal. This can help roaming salespeople or contractors do their jobs but can end up being a security headache. 

Software and Interface

The EX4100's web-based dashboard is one of the best in the business. In addition to having a bright and open design, the page shows everything you'll need to sleep soundly at night. 

The home page includes a large colorful circular graph of the drive's capacity that's excellent for at-a-glance viewing. It not only shows what portion is used but what type of files have been saved. To the right is a photo of the drive along with the current firmware level and the results of the most recent diagnostic routine. Both show blue check marks if everything seems OK and lead to more details if something appears to be amiss. 

Below are boxes for network activity graphs, as well as the number of current local users, online connections and internal applications being run. Across the top are links to dig into the drive's configuration and features that range from Home, Users and Shares to Apps, Cloud Access, Backups and Storage. The Settings section is deep and useful with the ability to set the RAID level, change the password and run several diagnostic programs. 

As is the case with Drobo's 5N2 RAID family's myDrobo App Platform, the EX4100 has third-party apps for adding specific tasks to the RAID array's repertoire. On top of using the drive as a web (HTTP) or file transfer protocol (FTP) server, you can back up data, connect to Amazon's S3 online file storage system or scan the EX4100's contents for malware. 

Support and Pricing

The EX4100 is a bargain at $350 for an empty case. With capacities ranging from 8TB ($700) to 32TB ($1,500), the device sells for a little less than other small RAID devices, like Drobo's 5N2. 

The EX4100 comes with one of the best warranties in the industry that covers the hardware and software for three years, a year longer than some of its competitors. Unfortunately, the company doesn't offer extended warranties or priority support on the EX4100. 

Despite its lack of expansion potential, Western Digital's MyCloud Expert EX4100 is a great RAID setup for a small business not only for its low price but for the ability to allow online access, encrypt data and recover files that might otherwise have been lost. At $700 for an 8TB storage system, it is a top choice for small companies with limited data needs and budgets.

Western Digital MyCloud Expert EX4100

Western Digital MyCloud Expert EX4100

The Verdict

A great choice for small businesses that aren't data heavy, the Western Digital MyCloud Expert EX4100 is inexpensive, can encrypt a company's worth of data and rebuild lost data. It is a perfect choice for a small business RAID array.

Brian Nadel Contributing Writer
Brian is a technology writer based north of New York City. He writes stories for, Tom's Guide, ComputerWorld and Scholastic Magazines. He is the former editor-in-chief of Mobile Computing & Communications magazine.