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.