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Seagate BlackArmor NAS 420 review: Seagate BlackArmor NAS 420

Seagate BlackArmor NAS 420

Dong Ngo SF Labs Manager, Editor / Reviews
CNET editor Dong Ngo has been involved with technology since 2000, starting with testing gadgets and writing code for CNET Labs' benchmarks. He now manages CNET San Francisco Labs, reviews 3D printers, networking/storage devices, and also writes about other topics from online security to new gadgets and how technology impacts the life of people around the world.
Dong Ngo
10 min read

Editors' note: The BlackArmor 420 is very similar to the BlackArmor 440. For this reason, you may experience some deja vu if you have already read the review of the 440.


Seagate BlackArmor NAS 420

The Good

The Seagate BlackArmor 420 comes with an excellent drive bay design that doesn't require tools to be accessed. The server offers decent performance and supports 3TB internal hard drives.

The Bad

The Seagate BlackArmor 420's throughput could be better. Its Web interface is sluggish and unfriendly to nonadvanced users. The four-bay server comes with only two hard drives and doesn't offer any way to expand the amount storage space without rebuilding the RAID from scratch. It might also have performance issues when used with with certain home routers' QoS feature.

The Bottom Line

Seagate BlackArmor 420 is a decent NAS server. However, not having the capability to dynamically change the current RAID setup's capacity makes it much less desirable for either home or business users.

The BlackArmor 420 is exactly the same as the BlackArmor 440, with one difference: out of the box only two of its four drive bays are occupied by a hard drive, leaving the other two empty. This actually makes a huge difference; for instance, when you add two more hard drives to the BlackArmor 420, you will likely have to back up your data and re-create the RAID before you can take advantage of all four bays.

Other than that, it is a relatively fast and reliable NAS server with a price that starts as low as $500 (for 2TB). Still, we'd recommend the BlackArmor 440; or, if you want faster performance and more features, the Synology DS410 or the Netgear ReadyNAS Ultra, instead.

Design and setup
The BlackArmor 420 NAS server has a bold-looking design with four bays on its front and a top part that protrudes farther out, showing off its tiny LCD. Each bay can hold one SATA hard drive of any capacity, meaning currently the device can host up to 12TB of storage. The 420, however, as mentioned, comes with just two hard drives, leaving the other two bays for you to add more storage later.

The device has a nice drive bay design that allows you to replace and add more storage easily without any tools. Seagate recommends you use only its hard drives. In fact, the company provides tech support only when you use its hard drives, but the BlackArmor will work with SATA hard drives from any vendors.

Considering its large size, the BlackArmor's fan is surprisingly quiet. Also, it is the first NAS server we've seen that allows you to replace the cooling fan completely if you need to. This will be a useful boon, as over time fans tend to collect dust, become noisier, or just stop working.

On the back of the BlackArmor are two Gigabit Ethernet ports and three USB ports, with another USB port on the front for quick and convenient thumbdrive use. The USB ports support both USB external storage devices and printers. A small LCD on the front displays the status of the USB-connected device, providing status information such as IP address, link status, date, and time. On the right side of the LCD are two navigation buttons that we found rather confusing to use at first because they are not labeled.

The BlackArmor 420's backup solution is based on Acronis' excellent True Image and comes with licenses for 10 computers. One of its more useful features is the capability to quickly recover a crashed computer by booting from the included software CD, allowing you to perform a complete system recovery from backup contained on the BlackArmor 420 NAS.

Thanks to the included discovery software utility, setting up the BlackArmor was a simple endeavor. Once you have everything set up, the utility assists in finding the NAS server on the network and will allow you to map network drives to its two default share folders, Public and Download. Fortunately, the utility isn't needed to access the NAS, because it fully supports the SMB protocol and can be easily found using Windows Explorer.

You can also use the discovery utility to launch the BlackArmor's Web interface, but that is where the simplicity ends. Unfortunately, you will need to figure out a lot by yourself, as we found the NAS server's manual is rather scant.

Though it lacks support for fancy features such as IP cameras or Time Machine, the BlackArmor 420 NAS server has a long list of features. In this review, we touch upon only those that we found significant or unique to this device.

General features
The BlackArmor has standard user account management. By default the device comes with an "Admin" account that allows you to log in and create other user accounts. Though this default account has administrative privileges, it doesn't include all of the features of a user-created account. For example, you won't be able to use the Admin account to access the NAS remotely over the Internet. This is rather confusing because in most, if not all, other NAS servers, there's nothing you can do with a regular account that you can't do with the "Admin" account.

Once a new user account has been created, you can assign it different access privileges for each share folder. Also, placing a user account in a group automatically gives it the access privileges of that group. Aside from public share folders, each user account has a private share folder of its own and if you have an office with a centralized server, the BlackArmor 420 NAS can be set to work as a domain member. Again, this part requires you to understand Windows Server's Active Directory as well as other advanced user account management.

The NAS offers four different ways to set up the hard drive: Raid 0, Span, Raid 5, and Raid 10. As only two hard drives are included out of the box, you have only the options of using either RAID 0 or RAID 1. Setting up a RAID configuration takes quite some time--about half a day with two 3TB hard drives. The servers, however, come set up with RAID1.

Unlike other NAS servers that offer dynamic RAID configurations, the BlackArmor 420 supports only standard RAIDs. Dynamic RAID configurations, such as the Sinology's Hybrid RAID or Netgear's XRAID-2, allow you to scale up the amount of storage space as more hard drives are added, without building the RAID from scratch. In the case of the BlackArmor, you'll have to back up the RAID, rebuild it with a new hard drive, then copy the data back if you want the old and newly added hard drives to be part of the same RAID setup. This hassle makes the server much less appealing than even its linemate the BlackArmor 440.

With built-in support for Digital Media and iTunes servers, the BlackArmor can automatically stream music, video, and photos to compatible devices, including computers, set-top boxes, and game consoles. To share these types of files, simply place them in their appropriate folder within the default Public share folder. For example, if you want to share music via iTunes, first place the music files in the Our Music folder, which is inside the Public share folder. Then you can set the intervals that the server will automatically scan for new music to add to the shared folder, ranging from every 5 minutes to once a day. We tried this out and it worked very well.

The BlackArmor NAS server supports the Network File System (NFS), which allows the system administrator to store resources in a central location on the network, providing authorized users continuous access to them. It can work as an FTP, an HTTP, and a secure HTTP (HTTPS) server. It also has support for Dynamic DNS through DYNDNS.com, meaning you can set up the above servers to work over the Internet for free.

Like most high-end NAS servers, the BlackArmor supports self-downloading with its Downloader Management feature. This allows you to run three download jobs at a time. In our test, the feature worked well with sites that require authentication. You can also schedule the downloading job to run at a particular time, for example at night, to avoid bandwidth congestion.

Remote access
The BlackArmor also comes with a very convenient way for you to access its data securely over the Internet via Seagate's free Global Access offering. This method of remote access was introduced first with the Maxtor Central Axis NAS server, but the BlackArmor brings it up a notch.

The BlackArmor supports multiple Global Access accounts, one for each user account on the NAS. For example, User1 can create a Global Access account, then log in to the NAS server via its Web interface to associate that Global Access account with the user account on the NAS. Then, User1 can go to the Global Access Web site and access that private folder as well as public folders on the BlackArmor from anywhere in the world. User2, User3, and so on can also, and all can do this simultaneously. Seagate suggests that the BlackArmor supports up to 50 users.

If logged in to the NAS from a remote location, you can transfer files back and forth between the remote computer and the NAS server. Though this vendor-assisted method of remote access is nothing new and can be found in other NAS servers, like the WD My Book World Edition , Seagate's Global Access enables easy copying of an entire folder from the NAS server to the remote computer, which is not available in the My Book. You won't be able to simply drag and drop the folder, however; instead, once you've selected a folder to download, the NAS server will compress that folder into a ZIP file and you'll need to decompress it once it's downloaded. This helps the file download faster and since Windows (and Mac OS X) support ZIP files natively, we didn't see this as a big hassle.

Back up and Dual Gigabit Ethernet
The BlackArmor offers by far the best backup solutions we've seen in an NAS server. The wizard-based backup software supports a long list of backup options, including incremental and differential backups. You can restore by running a restore wizard, by booting using the included CD, or by mounting the backups into a virtual hard drive and copying data using Windows explorer.

The NAS also comes with many options for backing itself up, including NAS to USB and NAS to NAS. The first allows backing up to USB external hard drives and the latter means you can back up one BlackArmor NAS to another. Either of these options can be used without a computer, at any time--manually or automatically.

The server supports external hard drives formatted using both FAT32 and NTFS file systems, allowing you to simply plug any existing USB drive into the NAS and immediately share its files. The NAS can also format external hard drives using the FAT32 file system, regardless of the drive's capacity. This is really useful, especially as Windows allows you to format only a hard drive that's smaller than 32GB using FAT32.

The BlackArmor 420 NAS server comes with two Gigabit Ethernet ports. These ports, in addition to allowing for the linking of multiple units together for NAS-to-NAS backup, can also be used for aggregation. Currently the NAS works well only with the Fail Over Aggregation option, where if one port stops working, the other will kick in immediately to prevent interruption. Going forward, however, Seagate has suggested that it will release a firmware update to allow the two ports to work together, increasing the throughput speed.

We tested the BlackArmor in both RAID 0 and RAID 1 and its performance was just about the average among other NAS servers we've reviewed.

In RAID 0 (which is optimized for performance and maximum amount of storage at the expense of data integrity), the BlackArmor 420's write speed was at 245Mbps, while its read speed was 567.1Mbps. For comparison, the same numbers for the Synology DS410 were 429.4Mbps and 867Mbps for write and read, respectively.

In RAID 1, which guards data against single hard-drive failure by making only half of the total storage available, the NAS' scores were slightly lower, as expected, at 188.8Mbps and 451.9Mbps for write and read, respectively. Again for comparison, the Netgear ReadyNAS Ultra did much better, with 443.7Mbps (write) and 875.2Mbps (read). Note, however, that the Netgear was set up in its proprietary X-RAID2.

Overall, the BlackArmor 420 posted decent data transfer rates, above average in reading and slightly below average in writing on our charts. With this performance it's capable of handling most data-sharing and media-streaming needs. However, since it offers the most amount of storage of any NAS, we wish its performance were on par with that of the Synology DS410 or the ReadyNAS Ultra.

CNET Labs NAS Performance Scores (Via wired Gigabit Ethernet connection)
(Longer bars indicate better performance)
Seagate BlackArmor 420 (RAID 0)
Seagate BlackArmor 420 (RAID 1)
QNAP TS-259 Pro (RAID 0)
QNAP TS-259 Pro (RAID 1)
Synology DiskStation DS710+ (RAID 1)
Patriot Valkyrie Dual-Bay (RAID 0)
Patriot Valkyrie Dual-Bay (RAID 1)

The BlackArmor 420 worked quietly in our test. We ran into a very unusual situation with it, however, when the NAS didn't work well at all with certain routers that had their QoS features turned on. More specifically, we experienced extremely slow read speed with both the D-Link DIR-655 and the D-Link DIR-825 when their QoS features were turned on. It's recommended that you turn off your home router's QoS when you use it with the BlackArmor 420.

Service and support
Seagate backs the BlackArmor 420 NAS server with a decent three-year warranty; much more than the one-year warranties of many other NAS servers. Toll-free phone service is available weekdays, 5 a.m. to 7 p.m. (PT), or you can e-mail technical support via a Web form. Seagate's support site offers installation and troubleshooting assistance, a download library, a knowledge base, and a drive troubleshooter.


Seagate BlackArmor NAS 420

Score Breakdown

Setup 9Features 6Performance 6Support 8