The DiskStation DS411slim is the second four-bay NAS server that's based on a 2.5-inch hard drive that we've reviewed, the first being its predecessor the DS409slim. Like other NAS servers from Synology such as the DS1511+ and DS410, the compact DS411slim has great performance and tons of features. It's not perfect, however, and could use some improvement in its Photo Station, which takes a long time to generate thumbnails, and in the sluggish Time Machine backup performance.
At the street price of $320 (no storage included), however, the DS411slim would definitely be a good investment for a space-conscious environment, be it a home or an office. If you want something that offers even better performance and more storage, we'd recommend the DS1511+.
Setup and ease of use
The Synology DiskStation DS411slim shares the same compact and eye-catching design as the DS409slim with the addition of a separate base that helps the bottom-facing fan ventilate better and also makes the whole package even more aesthetically pleasing. Unless you plan on putting the router on a fluffy surface, such as a carpet, this base is unneeded. With or without it, however, the device is tiny for a four-bay server, measuring just 4.72 inches tall by 4.13 inches wide by 5.6 inches deep, and weighs just a little more than 1 pound (without a hard drive).
Like the DS409slim, the DS411slim has a USB port and an array of indicator lights on the front. These lights show the status of the hard drives, the connection, and the power. On the side, toward the front, 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 thumbdrive connected to the USB port onto the server's internal storage.
On the back, the server has another USB port (for a printer or an external hard drive), an eSATA port (for high-speed external storage devices), a Gigabit Ethernet port, and the four drive bays. Each bay comes with a very sturdy tray that firmly holds the hard drive in place. However, you can pull the trays out of the bay fairly easily to remove and install hard drives.
The NAS server doesn't ship with hard drives and we tested it with four 2.5-inch SATA 500GB Seagate Momentus drives. The server will work with just one hard drive but if you want to take advantage of its RAID configurations, at least two are needed. The server supports a wide range of RAID configurations, but what we like most is Synology Hybrid RAID (SHR), which balances storage space and performance while guarding the data against a single-disk failure when applicable.
An SHR setup enables you to dynamically add hard drives to the RAID without needing to rebuild it from scratch. You can start an SHR setup with just one hard drive, and once the second hard drive is added, SHR will automatically change to a RAID 1-like setup; with a third hard drive or more it will move to a RAID 5-like setup. SHR also supports mixing and matching of hard drives of different storage capacities as long as the replacement hard drives have the same or larger capacity as the ones they replace. In our testing SHR offered the same performance as a RAID 5 setup. SHR is similar to XRAID 2 on the Netgear ReadyNAS Ultra 4.
The DS411slim comes with a small Quick Setup poster that illustrates the use of the included Synology Assistant software to get the server up and running. In our trials, the software quickly found the server in the network, and launched its Web interface for further management. Powered by DiskStation Manager 3.1 firmware (aka the operating system), the DS411slim, like other new servers from Synology, has a better Web interface by far than NAS servers from other vendors.
Sharing the same operating-system version as the DS1511+ and DS410, the DS411slim offers basically the same large set of features. The DS411slim differs from its siblings by supporting just eight IP cameras and only works with laptop hard drives, instead of full-size 3.5-inch hard drives.
The DS411slim offers basically all the features you'd commonly see in a high-end NAS server, including the ability to work as an FTP/HTTP server, media-streaming servers, support for user accounts, Active Directory, external hard drives, a printer, iSCSI, and even Time Machine backup for Macs.
On top of that, the DS411slim has features that you're unlikely to find in others, organized in a set of "stations," such as Surveillance Station, Download Station, File Station, and Photo Station. All of these stations can be accessed via the local network or over the Internet. Some of them also come with mobile applications for the iPhone or iPod Touch or Android-based smartphones.
We tried out these features and they generally work well, except for Photo Station, which is designed to allow easy organization and sharing of photos in album form, much like Google Picasa. Basically, Photo Station automatically turns any folder of photos into an album and you then can add comments, share with others via the Internet, and even add them to a blog. Unlike the DS1511+ or the DS410, however, the DS411slim took a long time in our tests to generate thumbnails. We tried about 50GB's worth of photos and that took about a day for the thumbnails to be fully generated. During this time, the server's overall performance was lowered. Once generated, the album worked well, however, and we found out that you can avoid this problem by adding a small number of photos at a time.
As mentioned above, the server's Surveillance Station supports up to eight IP cameras. Unfortunately, only one camera license is included and you'll need to buy more for the server to support more cameras. The licenses are not cheap, costing $50 each. Once set up, Surveillance Station works as a comprehensive surveillance digital video recorder. This feature worked really well in our trial. We could view live images and record them based on scheduling or motion detection. When multiple cameras were used, we could even synchronize the playback to see what was recorded by different cameras at a given time. Basically anything you want to do with a surveillance system, you can do with the server's Surveillance Station. The DS411slim supports a long list of IP cameras and is able to automatically detect those connected to the local network to facilitate the setup process. Synology also offers an app called DSCam for Android devices and the iPhone, so you can manage your surveillance via your mobile device even when you're out and about.
We also loved the server's Download Station, which supports Web sites that require authentication (such as the RapidShare, eMule, and BitTorrent file-sharing services). Unfortunately, however, its Download Director software desktop application, which enables you to remotely manage 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 such as RapidShare, you'll need to log into the NAS' Web interface to do so. The interface, unfortunately, can't remember passwords of download Websites other than RapidShare and Megaupload. This means you will have to manually type in the credential for each download, which could be a hassle.
The DS411slim has built-in backup options that are focused on backing up its content on an external storage device or a network location. For backing up files on your computer to the server, Synology includes its Data Replicator backup desktop software.
Data Replicator 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 DS411slim's storage. The software has a nice feature that helps you find and quickly back up e-mail archives, which generally are buried deep in layers of subfolders within a user profile. In addition, it enables you to schedule and keep track of the backup process via e-mail notification. Nonetheless, we find the software primitive. It also tends to freeze once in a while when a large amount of data is being backed up. We'd recommend using third-party backup software with the server.
All in all, even with the Photo Station hiccup and the lackluster backup software, we found the DS411slim one of few NAS servers on the market that offer the most and the best features for both home and business use.
We tested the DS411slim RAID 0 and SHR configurations and it did well in both, though didn't top our charts.
In SHR, which is the recommended setup, the server scored 40.9MBps and 78.4MBps in write and read tests, respectively. These scores put it in the top three on our charts, behind the DS1511+ and the Netgear ReadyNAS Ultra 4, which are both full-size NAS servers.
In RAID 0, the DS411slim did much better in writing at 57.8MBps, but, interestingly, worse in reading at only 67.2MBps. These scores were nonetheless among the fastest NAS server scores.
Despite these high numbers and very good overall data transfer rates, the DS411slim seemed very slow when it came to backing up a Mac using Time Machine. The process took about 50 percent longer than we expected. Other than this, we were happy with the server's performance.
The NAS performed quietly in our test and remained cool even during heavy loads. Note that our lab has a relatively high ambient noise level, which means in a quieter office you might notice the sound of the server's cooling fan.
Service and support
Synology backs the DS411slim 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. PT. At the company's Web site you can find Synology's forum, download software and firmware, and get more information about its products from its Wiki page.
In conclusion, the DS411slim would get a four-star rating or even an Editors' Choice Award if its Photo Station and support for Time Machine were better. But even with these two minor shortcomings, this is still one of the best NAS servers you can find on the market and it is currently the best compact NAS server.