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Synology DiskStation DS409slim review: Synology DiskStation DS409slim

Synology DiskStation DS409slim

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
7 min read

Synology Disk Station DS409slim is a true miniature powerhouse in the network-attached storage device market. It's the first 2.5-inch hard-drive-based NAS server we've reviewed that offers hot-swappable capability. However, that is its least impressive feature. The server did well in our performance tests and, like other Synology products we've worked on, including the DS107+ and the DS209+, it comes with a vast array of features, great expandability, and a top-notch user interface.


Synology DiskStation DS409slim

The Good

The Synology Disk Station DS409slim offers fast performance, a robust Web interface, and a generous feature set in a compact, aesthetically pleasant, and practical design.

The Bad

The Synology Disk Station DS409slim doesn't come with any storage and is not easy enough for novice home users to use. Its Surveillance Station requires additional license fees to support more than one IP camera and its Download Station's software doesn't fully support Web sites that require authentication.

The Bottom Line

The Synology Disk Station DS409slim makes an excellent NAS server for both home and small business applications, and it fits especially well in offices with limited space.

Priced by retailers anywhere from $390 to $430, the DS409slim is relatively expensive considering you must pay more for the necessary hard drives. A lot of other NAS servers (such as the WD My Book World Edition , or Iomega SctorCenter ix2-200, to name a few) cost about the same but come with terabytes of storage already included. Also note that because the DS409slim supports 2.5-inch hard drives, its ratio of price per storage is much higher than that of most 3.5-inch hard drive-based NAS servers. To make up for this, the DS409slim is uniquely compact, looks great, and offers features that are not available in many other NAS servers.

If you have a small office space, a big interest in networking, and want to get the most out of your NAS server, the DS409slim will be worth your investment.

Setup and ease of use
The Synology Disk Station DS409slim looks cute; it bears more of a resemblance to a fancy Apple accessory than to a storage device, despite its black color. It also comes in a very compact package, measuring just 4.72 inches tall by 4.13 inches wide by 5.6 inches deep, and weighs just a little more than a pound (without a hard drive).

On the front, the unit has a USB port and an array of indicator lights showing the status of the hard drives, the connection, and the power. On the side there's a vertical copy button right under the on/off switch. This is a useful feature that allows you to quickly copy the entire contents of a thumb drive onto the NAS' internal storage. On the back is another USB port (for printers or an external hard drive), an eSATA port (for high-speed external storage devices), a Gigabit Ethernet port, and, of course, the four drive bays. Each bay comes with a very sturdy tray that firmly holds the drive; nonetheless, you can easily remove and install a drive on the tray using a screw driver. The trays can be pulled out of the drive bays easily.

The cooling fan, located on the bottom of the unit, is larger than we'd expect for a drive of this size. The DS409slim's four "feet" give it ample clearance for ventilation.

We tried the DS409slim with four 32GB hard drives, though only one is necessary. If you want to set up the drives into a RAID configuration, you'll need at least two hard drives for RAID 1 and RAID 0 and at least three for RAID 5. Also, the drives can be configured in RAID 6 and JBOD setups. It only takes a minute or so to switch the DS409slim's hard drives from one setup to another if you choose not to perform the disk check. With disk-checking, this time increased to about 30 minutes, which is still relatively still short compared with other NAS servers that can sometimes take hours to complete the same job. This time will vary depending on the capacities of the attached hard drives.

It was easy enough to set up the DS409slim, though there's no help manual included in the package. The device comes with a CD containing Synology Assistant software that helps map network drives, installs a printer (if you want to connect a USB printer to the NAS server), and launches the Web interface to manage the server. The Web-interface is one of the best user interfaces for NAS servers we've seen.

Once launched, all features and functions of the DS409slim are listed in a well-organized menu on the left of the interface. Most of the setup section is a wizard that guides you through. For example, when we clicked on "Share Folder" and then clicked "Create," a wizard launched to walk us through all the steps involved in making a new share folder, assigning user access to that folder, etc.

Running Synology Disk Station Manager 2.2 firmware, the DS409slim shares the same robust feature set as the DS209+ had. The DS409slim's Surveillance Station now supports up to 8 cameras (down from 10 in the DS209+, possibly due to the size of the unit). Unfortunately, just like with the previous model, only one camera license is included and you'll have to pay $49 each for any additional licenses. Thus, using the DS409slim as a complete surveillance system would require you to spend an extra $400 or so just for the camera licenses (apart from the cost of the cameras themselves, of course).

The second significant feature of the DS409slim is its Download Station, which supports Web sites that require authentication (such as RapidShare, eMule, and BitTorrent file-sharing services). Unfortunately, however, its Download Director software desktop application, which allows for remotely managing the Download Station, doesn't support starting a new download from sites that require authentication. So if you want to download a big file from a subscription service, you'll need to log into the NAS' Web-interface to do so. The Download Station also doesn't keep track of RSS feeds.

Like with the DS209+, the DS409slim comes with Photo Station 3, which allows you to easily to organize photos into albums and may be the device's biggest selling point for home users. Once activated, a share folder called "photo" will be created on the DS409slim. One you've dragged your photos into this share folder, the DS409slim will take care of the rest and turn each folder of photos into a well-organized, customizable album. You can then browse the album via a Web browser and (just like with Google's Picasa Web album ) you can very easily add captions and comments to each photo and album.

Furthermore, Photo Station includes a blogging function, which allows forwriting your own blog linked to the photo album. You can also create user accounts to allow and limit access to the photo album. We tried a folder of about 500 photos and the NAS server took about 10 minutes to generate thumbnails for them all.

The DS409slim gives you access to the Photo Station feature over the Internet, just as long as you're able to set the NAS up with a dynamic Domain name system (DDNS) , or you can access the Internet with a static IP. You'll need to know quite a bit about networking in order to do this, such as how to forward certain ports to certain IP addresses, etc. Synology provides rather scant instruction regarding how to set it up, partly because this depends on each router you use. The DS409slim supports four DDNS services: 3322.org, NoIP.com, Two-DNS.de, and DYNDNS.org.

Additionally, you can use the DS409slim as a Web server, a MySQL server, a file station server, and as an audio station where you can listen to audio files contained on the DS409slim via USB speakers or stream them to other computer or devices.

The DS409slim has built-in backup options focused on getting content from the device onto a USB or eSATA external storage device or a network location. For backing up files on your computer to the DS409slim, Synology includes its Data Replicator 3 desktop software.

The Data Replicator 3 is a simple, straightforward backup application that allows you to quickly copy data (much like copying and pasting using Windows Explorer) from your computer to the DS409slim. The software includes a feature that helps you find and quickly back up e-mail archives, which are generally buried deep in layers of subfolders within a user's profile. In addition, it enables scheduling and keeping track of the backup process via e-mail notifications.

We tested the DS409slim in JBOD, RAID 0, and RAID 5 configurations and it did well in all three, though it was not the best we've seen.

In RAID 5, which is the recommended setup, balanced between data protection and disk space, the NAS server scored 191Mbps for write speed and 219Mbps for read speed. These numbers are comparable to those of most USB 2.0 direct-attached external hard drives, which are supposedly faster than NAS servers.

In RAID 0, the setup that gives you the most storage space and the best performance at the expense of data protection, the DS409slim scored noticeably faster, at 218.1Mbps for write speed and 240.88Mbps for read speed.

In JBOD setup, where hard drives are linked together without any protection or performance enhancement, the DS409slim scored 217Mbps for write speed and 228.48 for read speed.

Overall, these numbers were not the fastest we've seen, but were among the average of high-speed NAS servers. Still, considering the physical size of the DS409slim, we were happy with its performance.

The NAS also performed quietly in our tests and remained cool even during heavy loads. Note that if you have a very quiet office, you will notice the humming sound of the cool fan, however.

CNET Labs NAS performance scores via wired Gigabit Ethernet connection (in Mbps)
(Longer bars indicate better performance)
QNAP TS-239 Pro
Synology Disk Station DS409slim (RAID 0)
Apple Time Capsule
Maxtor CentralAxis (Single Volume)

Service and support
Synology backs the DS409slim with a two-year warranty from the date of purchase. Phone tech support is available Monday through Friday, 9 a.m. to 5 p.m. PST. At its Web site you can find Synology's forum, download software and the latest firmware, and get more information about Synology products from its Wiki page.


Synology DiskStation DS409slim

Score Breakdown

Setup 10Features 8Performance 7Support 8