WD My Cloud EX4100 4-Bay Expert Series 16TB NAS Review

by - 5 years ago




We ain’t all equally skilled when it comes to the configuration of network and storage devices nor is it everyone that has the same interest in that. Sometimes you just want to purchase something, enter your preferred name and password, and then be ready to rock.

WD’s My Cloud series is designed for just these scenarios and it comes equipped with drives and is pre-configured. All you need to do yourself is connect it, turn the power on, and set your password. Today I’m taking a closer look at the WD My Cloud EX4100 from the Expert series and will give it a good spin in the test area.


The MyCloud EX4100 it is a 4-bay NAS unit and in this case it comes pre-loaded with four 4TB WD RED drives. Other disk configurations are available if 16TB shouldn’t be the right match. You can get it from driveless all the way up to 24TB raw capacity.

You will need some power on the insides to handle what the EX4100 promises and it comes with a dual-core Marvell ARMADA 388 processor that clocks at 1.6GHz and 2GB DDR3 memory. This should be plenty, but if it shouldn’t be then the EX4100 also comes with three USB 3.0 ports allowing you to connect extra external storage.

Two gigabit Ethernet ports take care of the network traffic and they fully support both port trunking and link aggregation for failover redundancy and improved traffic capabilities.

A nice bonus for every device is the built-in display at the top of the unit. It allows you to quickly see what’s going on with your unit, its name, network details, and storage setup. It will also keep you updated on the progress when you changing major configurations such as the drive setup.


Just because the unit comes pre-equipped with four drives doesn’t mean that you can’t replace them with smaller, bigger, or just other ones if you want to – or in case you bought a driveless unit. The EX4100 supports hot-swapping and comes with easy-release front bays for quick access. Pop the slider and the drive will eject.


It comes as no surprise that WD used their own RED series of NAS drives in these units. They are built especially for NAS usage, so what better to pick. In this case, the unit is equipped with four of these 4TB drives. The WD RED series uses an IntelliPower RPM systems up to 5400 RPM and come with 64MB Cache.


The EX4100 doesn’t have any dedicated drive trays and is as such tool-less to upgrade. The drives are still firmly secured inside thanks to the large dividers. Not using drive caddies allows for a smaller and more narrow footprint, something anyone can appreciate.

The EX4100 supports RAID 0, 1, 5, and 10 as well as JBOD and Spanning. While the RAID 0 to 60 modes are self-explanatory, how the terms JBOD and Spanning are used variates a bit, including Single disk. Essentially, JBOD and Spanning is the same thing but with a small difference. JBOD stands for Just a Bunch Of Disks, these can either be presented as single volumes or one large where they are used as extension for each other. Spanning, on the other hand, will create one large volume with all the drive space available and the drives don’t even need to be the same capacity.

JBOD stands for Just a Bunch Of Disks, these can either be presented as single volumes or one large where they are used as extension for each other. Spanning, on the other hand, will create one large volume with all the drive space available and the drives don’t even need to be the same capacity.

In the EX4100’s case, JBOD will result in four individual volumes and spanning will create one large volume without redundancy or performance improvements. As always, which mode i

As always, which mode you chose is down to your own needs. Whether you need a maximum amount of capacity, redundancy, performance improvements or a little of each.


Storage is just one side of the story, you also need to connect that storage somehow. The EX4100 comes with two Gigabit Ethernet ports that support both failover and port trunking.

The addition of a dual power supply system with a backup for emergency situations is awesome and something more NAS should feature. Any product can break for one reason or another and it should have a backup solution in case that happens.

The single and relative large 120mm fan helps to keep everything cool without creating too much noise. It only needs to rotate at low speeds to keep everything cool and operate optimally.


So far I’ve talked a lot about the hardware, but that’s just one side to the story. The software has to match with the right features, otherwise what would be the point.

It doesn’t matter if you want to connect to the WD MyCloud EX4100 from Windows, Linux, or your Mac OS based system, everything should be covered with Samba, Bonjour, and NFS3 support. The EX4100 also support VLAN, UPnP, iSCSI, SSH, and WebDAV and comes with an FTP server.

It is well suited to stream all your stored content to anything from smart devices to TVs and media players. Twonky’s UPnP media server, DLNA, and iTunes server are all present and it supports connection to devices such as WD TV Live, Xbox 360, PlayStation 3, Windows 8, connected TVs, Blu-ray players and digital picture frames.


Security is important everywhere and WD has that part covered too with features such as Active Directory support and 256-bit AES full volume encryption.

You can set up backup plans to local and remote locations as well as the same system, use Apple’s Time Machine, or use the cloud-based services Amazon and ElephantDrive. You can also sync drives with the attached USB 3.0 ports.

Security also involves power management and the EX4100 doesn’t just come with redundant PSU support, it can also control both network and USB connected UPS power backup devices.


Within the package you’ll find the NAS device with the drives inserted, a network cable, a power supply and, in this case two connector cables: one UK and one EU. There’s also a startup guide that will get you set up, even if you don’t know the darndest thing about NAS systems.


Remote access can not only be achieved through the web interface, you can also get both a desktop application and several mobile apps for your Android and iOS devices.


Other features such as a download server for both HTTP and P2P services, being IPv6 ready, supporting jumbo frames up to 9000 bytes, and SNMP for easy administrator management in larger environments are also all present.

If you’re concerned about the environment and having a device running all the time, then WD has you covered too. It features disk spin down when not need, which also will increase the drives lifespan, wake-on-LAN, automatic power recovery, and scheduled power on-off times.


The PCB has a simple build where only one side is utilized. The memory is soldered onto the board, so you can’t upgrade that, but that would also be kind of missing the target audience for a pre-setup unit.

We see that the memory used comes from SKhynix and the LAN ports are controlled by two Marvell 88E1512 chips. The USB 3.0 ports are controlled by a Renesas µPD720210 4-port hub controller.



System Specifications, Features & Power Consumption

Technical Specifications


There are four different capacity models available for the My Cloud EX4100, ranging from zero to 24TB capacity.



WD’s MyCloud operating system has a very user-friendly and bright interface. A Navigation bar at the top will show the categories while the field below will show the appropriate information or options.


Power Consumption

The chart contains the actual power consumption measured at the PSU connection and while loaded with a maximum amount of drives. Peak, or maximum, power draw will occur during boot times.



Setup – Initialization & Storage

There are several ways to get started with your new NAS, but in most cases you can do it really simple. You’ll just have to open your normal Windows File Explorer and navigate to your network environment. If auto-discovery is turned on, your brand new WD MyCloud EX4100 will show up and all you have to do is right-click it and select view device web page. This method will work with almost any networked device

This method will work with almost any networked device, but there are more. You can use either of the URLs provided in the installation guide and also get the Android or iOS mobile apps.



One of the great things about this unit is that it comes pre-setup. This means that you just have unpack, connect and power it on to be ready to serve your files. Well, that is almost. We do need to provide 3 things.


We need to set an administrator password to be able to connect to it add change things if you want to and you can also connect directly with your WD account – or create a new one if you don’t have one already.



And that’s all she wrote. Before you close the initialization you can specify whether you want to the NAS to automatically download and apply new updates, you can register for better support, and also participate in the product improvement program.


Storage Setup

As previously mentioned, the My Cloud EX4100 comes pre-setup and you don’t need to change anything – but that doesn’t mean that you can’t. WD’s My Cloud operating system works very simple and is easy to use even for beginners.

If you want to change your storage setup, this should be one of the first things you do – you wouldn’t want to lose the data you already copied to the NAS and have to do it again.


Changing the RAID mode is as easy as the initialization was. A few simple steps and you’re done. The first thing you need to pick is the disk mode.


The NAS will run a short self-test on all drives to make sure that they are in working order.


Next you can set the amount of space you want to assign as a new volume, the most obvious choice will be everything – but the choice is yours. You can also create multiple volumes on the same disk array.


The last two steps could have been put into one as they don’t involve much. You can set whether the system should auto-rebuilt the RAID setup if needed and whether encryption should be enabled or not. Encryption adds another layer of security to your system, but also costs you some performance in return.



Some RAID modes can migrate where others will need to re-format the whole thing. Press the finish button to set the process in motion.


The NAS will work for a little while after which it will post the result and you can close the popped guide. That’s all there is to it.


Encryption works per volume and can be enabled when you create it or at a later time through the settings.


Setup – Users, Services & Backup


Users are the foundation to connect to the NAS and you should create at least one user more than the admin. It isn’t recommended to use the admin account all the time.


Adding a user is real easy, just hit the add button and enter a username. Anything else is optional, but I recommend that you also set a password.


You can also add multiple users at once by an automated process. The user names will be generated out of the prefix you provide and incremental numbers starting from where you want it to. You can also assign quotas to all the new users right away.




You can edit all your users at any time, so no worries if you should make an error. Just fix it or add and remove rights at any time.


User Groups

User groups make it easier to maintain a lot of users at once. Instead of having to set access rights and privileges for all users individually, you just set them to the group. Only one place to edit instead of possible hundreds.


All you need to create a group is a name and some users to put in it, that’s all.


You can also set quotas and edit memberships at any time.


Shared Folders

Connecting to the NAS isn’t everything, we also want to add some shares for out files. The is a public folder default and every user will also get their own directory for personal files. Besides that you can create many more to suit just your needs, examples could be Media, TV Shows, Movies, Pictures, and Backup.


Just hit the add button, select a volume and give it a name and optional description and it’s ready.




Setup – There is more, Add-Ons & External Devices

Cloud Access

Pairing your new My Cloud NAS with your mobile devices is a piece of cake and only involves a few steps.


You’ll need to set up your MDMyCloud.com login and that’s it.WD_MyCloud_EX4100-SSCloud-user-info


As previously mentioned, there are a variety of backup methods. The main one will probably be the USB backup where you can create both manual and scheduled backups to your local USB based drives. Copy and synchronize are both available as options.



Remote backup adds the extra security if something should happen to the physical location, this could be theft, fire, or water damages for example. Having your files backed up to a remote location can give a big advantage and the whole thing can be automated.



The Internal Backups could also be called folder backup, as that is what it does. Create backup or synchronize folders on the same NAS unit.



If you don’t want to have another NAS located offsite but still want the benefits of having a remote backup, then the public cloud would be an obvious answer. When we say public, it doesn’t mean that your files are public, but that it’s a commercially available service that might or might not have a free option.


In this case, we have ElephantDrive and Amazon S3 as options, which you pick is your choice.



The Final backup solution is meant for cameras. You can set it to automatically detect when you connect your digital cameras and copy the files onto your NAS.


Apps and Add-Ons

There is a list of pre-installed apps on the server and you can also install more if the function you need isn’t there already. But let us have a look at what is there first.

The first three apps could be considered as one, a download manager. You can let your NAS handle HTTP, FTP, and P2P itself without the need to have your PC running.



You can also schedule when the downloads should be active so you they don’t hog the bandwidth when you need it otherwise.


The fourth pre-installed app is the Web File Viewer that allows you to manage the stored files directly from the admin interface and thereby any browser.


You can add a list of apps directly from the WD My Cloud system or manually add a third party app that you downloaded another place. You can also create your own apps.


The available apps at the time of writing where aMule – peer to peer file sharing application, Icecast – media streaming app, phpBB – Internet forum application, Joomla! – content management system, SqueezeCenter – streaming audio server, phpMyAdmin – My SQL administration tool, WordPress – blogging tool and content management system, and Transmission – BitTorrent client.



Mobile Impressions

A device that has the label MyCloud needs a mobile app, and WD doesn’t disappoint here either. You’ll for example find the WD My Cloud app in the Google Play store as I did here.


Once installed, you’ll need to connect with your NAS. This is just as easy as setting up the unit and is done in four easy steps.


If you’re connected to the same network, the App will find the NAS automatically and you’ll just have to push the add button. There are other ways to add the server and other services that can be added as well.


You can select when your files should be backed up and to where.


And that’s it. You are setup and connected to your NAS. Pressing the three lines to the left will show your devices and give you access to settings and activity.


Activity is shown both in-app and in your phone’s notification area, so you won’t miss what’s happening.



Testing Method


Test system:

Disks in Product:


  • Switch: Netgear ProSafge GS724TPS
  • Mode: IEEE 802.3ad

We would like to thank our sponsors for supplying us with the components needed for the test system as well as drives.

Software used:

The performance of the system we use to test with isn’t a major factor when testing a device of this sort. The performance of the NAS box comes down to the network it is running on, the protocol used to connect, and its own internal hardware.

With a device of this sort having so many different applications, Intel’s NASPT software covers all the bases and also gives us a set of results that we will be able to utilise and therefore give a benchmark against other similar systems in the future.

Intel NASPT (Network Attached Storage Performance Toolkit) performs its test by transferring varying sizes and quantities of data to and from the device based on twelve different scenarios.


As part of the testing, the NAS is connected through a Netgear GS724TPS managed Gigabit switch and then to our test bench to give the best real world setup test that we can and the NAS itself will be packed with Western Digital’s latest RED NAS drives. Intel’s NASPT software does require us to drop the memory down to 2GB, as using any more would lead to data caching and therefore skew the results.

I will be testing the NAS box performance under each of the RAID options that it has available as well just a single drive. The USB 3.0 speeds will be measured with our trusted Angelbird SSD2go Pocket drive.


HD Video Playback

HD Video playback is a read test, where a single 2 Gb file is read in 256 kB blocks sequentially from the drive. This simulates where a 720p HD video is being watched across the network to a media player on the other end.



2x HD Video Playback

2x HD Video Playback works with exactly the same data set as the first HD Video test, however this time the same content is streamed twice from the NAS box simulating two simultaneous streams being made to external media players.



4x HD Video Playback

In the same way that the 2x Video Playback streams to the equivalent of 2 external media players at the same time, the test here doubles that again up to a simulated 4 media players.



HD Video Record

The HD Video Record test is as the name suggests a write test to the NAS box. A single 2 GB file is written to the device in 256 kB blocks sequentially to the disk.



HD Playback & Record

The HD playback and record test now put the drive under the same single record and playback tests as before, but now at the same time. This will factor for the quick changes needed to switch between reading and writing two large blocks of data across the network to the device.



Content Creation

For content creation, Intel have simulated access to via video creation applications. This is made up of 98 files with 12 MB reads and 14 MB writes in varying sizes of blocks. The activity is predominantly non-sequential with the majority of access time made up of writing to the drives. There are quiet periods of read/write activity interrupted with busy periods to present a difficult workload on the drives.



Office Productivity

The office productivity simulation is very similar to the content creation, with a total of 607 files written to and read from the drive. A total of 1.4 GB of data is written to and read from the drive with a close balance between each made – the majority of write access is made up of 1 kB writes.



File Copy To NAS

This test quite simply put copies a single large file from the test system to the NAS box to show how well the system can sustain a single write speed. The 1.4 GB file is copied to the drive and written in 64 kB blocks.



File Copy From NAS

File copy from the NAS works in exactly the same way as the copy test, however it works in the opposite direction. The single 1.4 GB file is read off the NAS in 64 kB blocks.



Directory Copy To NAS

In the directory copy to NAS test, a directory tree representing that of a typical commercially available office suite is copied to the NAS to trace the bulk copy of a complex directory. A total of 2833 files making up 247 MB are moved, but the file sizes vary considerably with an average size of 41.4 kB. Due to the varying sizes of the files, only around 50% of the writes are sequential.



Directory Copy From NAS

In the same way that the file copy from NAS traces the same file back across to the test system, the directory copy from NAS does exactly the same but to the entire directory that it copied across previously.



Photo Album

Last of all is a test based around a photo album. When a photo album is viewed on-screen, only the images that you see are loaded from the drive and so when you scroll through the album, the new images have to be fetched and read. The album here contains 169 photos with varying file sizes based on the size, quality and detail in the image. Reading the files in a photo album puts an unusual read load upon the drive as the metadata is read, a thumbnail constructed and finally the image viewed.



Complete Benchmark: Average Throughput

Intel NASPT provides a summary at the end of each benchmark, included in this is the average throughput from all the previous test as one number. This is a pretty good overall view of a device and as such I’ve started to included this as well. The numbers below are the average of the previous 12 tests.




As mentioned previously in the review, security is an ever-growing concern and encryption is a great step to achieve this. As such I will be including a comparison between an encrypted drive and a normal single drive for a basic comparison and to show if and how it will impact on your performance.


Our benchmarks are real-world test and will variate a little, but it clearly has some impact on the performance here. We still get some good speeds, but not as good as the tests without encryption turned on.


Final Thoughts


When you first look at the price of this unit, you’ll think that it’s expensive. But as soon as you realize that you also get four 4TB WD RED NAS drives along with it, then you know that you were wrong. At the time of writing, the WD MyCloud EX4100 16TB at Amazon for $921.49, at Scan UK for £1036.52, or find a great deal through Geizhals.

If you’d prefer the unit without included drives, then you could pick up a driveless EX4100 at Overclockers UK for just £279.98 or NewEgg for $448.99. As you see, the prices variate a lot, so shop around and I’m sure you’ll find a great deal. WD also has their own web store.


The WD My Cloud EX4100 is a very standard looking black NAS unit. Four front accessible and hot-swappable drive bays, and a USB port with one-press-key copy function. WD also added a two-line display that can provide you with device and setup information. It is a simple design that will fit well in most environments.

This was the easiest to set up NAS I’ve had so far, really all I had to do to get going was to unpack it, connect the cables, and power it on. A two-step initialization and I could start. That is awesome and it is something a lot of casual users will appreciate and I doubt that even the most novice user would have trouble doing it.

The EX4100 didn’t have any trouble with performance either, scoring great with every disk configuration. The dual gigabit Ethernet is a nice touch that will give you redundancy and improved traffic capabilities. I really love that WD added a redundant PSU system too, this is a great bonus and added security and one that I wished more would use.

The USB 3.0 ports support external storage devices just as well as UPS monitoring and the Media Transfer Protocol (MTP) and Picture Transfer Protocol (PTP). The one-touch copy button on the front allows you to easily backup files from your thumb drives, smart phones, cameras, or other USB devices directly onto the NAS.

While this is an easy to set up and us NAS, enterprise users will still get the features they need. May it be IPv6, iSCSI, comprehensive backup solutions, or VM and authentication usage. The EX4100 does all that and more.

Basic apps are included for media streaming as well as file sharing and downloading, but you don’t need to stop there. You can expand the functionality with third-party add-ons such as aMule, Icecast, Joomla, SqueezeCenter, WordPress, Transmission, and more.


  • Pre-configured including hard disk drives
  • Solid performance
  • Good features
  • Dual Gigabit Ethernet
  • Dual PSU support
  • USB 3.0 with one-touch copy
  • LCD Display


  • no eSATA

“I doubt you’ll find an NAS that is easier to set up. The pre-configuration allows you to use your new NAS right away, even if you should be a novice user. Advanced and enterprise users will also find the features they need from cloud and backup to servers and authentication.”


WD My Cloud EX4100 4-Bay Expert Series 16TB NAS Review

Thank you WD for providing us with this review sample.

Article Index

  1. Introduction
  2. System Specifications, Features & Power Consumption
  3. Setup - Initialization & Storage
  4. Setup - Users, Services & Backup
  5. Setup - There is more, Add-Ons & External Devices
  6. Mobile Impressions
  7. Testing Method
  8. HD Video Playback
  9. 2x HD Video Playback
  10. 4x HD Video Playback
  11. HD Video Record
  12. HD Playback & Record
  13. Content Creation
  14. Office Productivity
  15. File Copy to NAS
  16. File Copy from NAS
  17. Directory Copy to NAS
  18. Directory Copy from NAS
  19. Photo Album
  20. Complete Benchmark: Average Throughput
  21. Encryption
  22. Final Thoughts
  23. View All

Author Bio

Add a Comment

Related Posts