Synology Disk Station DS408 Review

Nemo - 2009-01-17 20:04:05 in Storage / Hard Drives
Category: Storage / Hard Drives
Reviewed by: Nemo   
Reviewed on: March 3, 2009
Price: $749


Storage is one of those topics that's often addressed in terms of how much/how fast one's local hard drives are. As many homes expand to multiple computers and networked computers are more the norm these days, having the ability to share files easily among computers regardless of which operating system they might be running becomes more of an issue. This is especially true for the small office/home office or even workgroup computers in a small business or corporation.

For those that need more than just a few extra gigabytes of storage and those lacking a dedicated IT staff, one of the best options can be a network attached storage server. These devices are servers that offer a common repository allowing users to share files across the network as well as providing remote access to files over the Internet. As you move up the food chain, you begin to see more in terms of not only storage capacity, but also faster transfer speeds as well as more features. For some NAS servers the list of extras can be quite extensive and include iTunes, FTP and print servers but also more advanced features such as photo sharing, web servers and provisions for video surveillance recording. These type of servers are geared more toward office environments or serious video applications that demand more from a NAS server.

Synology Inc. is a company dedicated to manufacturing NAS servers for home, small business and corporate uses. Headquartered in Taipei City, Taiwan, Synology has been in business since 2000 and has also begun to offer portable and USB storage devices along with their network storage products. Our review unit is the Disk Station DS408 four-bay high-speed NAS server that can be configured in multiple RAID configurations. Let's see just how well this unit performs and what it has to offer.

Closer Look:

As is typical, we'll start out with what I like to call the box tour. Like a lot of products shipped for review, the DS408 came encased in a sturdy cardboard shipping box and survived its trip without incident. The front of the box offers up a picture of the NAS server and a list of the more salient features. The back side of the box looks like a virtual mirror image of the front but it also includes a list of the package contents. The end of the box contain graphics showing typical applications. The opposite end gives the viewer a list of detail specifications and a look at the connections and buttons on the unit.




Enough of the outside of the box, let's open it up and see what's inside. Once the tops flaps are open you can see there is a cardboard cap protecting the unit with the power supply cord resting along side it. Underneath the cap is the unit itself with a box containing the accessories. The unit is fully encased in a thin foam sheet envelope to protect it from scratches. The accessories include the power cord and packed inside an inner box, you'll find everything you need to install the hard drives and get connected including the external AC power adapter, a Cat5e patch cord, a bag containing 4 SATA hard drive power and data cables and a bag containing hard drive mounting screws, a pair of cable ties for cable management and a cable lock for securing the eternal power cord to the unit. You also get some product literature and an installation CD containing a quick installation guide, setup wizards and the user manual.


Once you have the unit out of the box and free of the protective foam sheath you start to get a feel for the shape and size of the DS408. The unit is roughly cube shaped with rounded edges on the front and a slanted control panel containing the power button and LED status and activity lights. The unit comes packaged with a protective film covering the front panel, which is a nice touch as it further protects the all plastic panel from getting scratched. The film peels offs easily and there's no sticky residue or anything to worry about. Once the film is removed you can see the large circular power button in the center with status and LAN activity LEDs on the left side and four HDD activity/status lights on the right side. The angle shot better shows the contour of the front panel and just how glossy the plastic is. You can also see there are generous ventilation slits along the top and bottom of the front panel. The rest of the case is all steel and has a rather sturdy, well-built feel to it. The back of the unit reveals the 80mm cooling fan and connections for the power unit, LAN connection and dual USB 2.0 ports for connecting external hard drives. The rear panel is hinged and secured by four thumb screws. Removing the screws allows the top part of the rear panel above the connections to drop down, giving you access to the interior of the unit for hard drive installation and change out. The bottom of the case has four rubber feet to keep it securely seated on a flat surface and for protecting other units if you need to stack them vertically.


Now it's time to open this unit up and install some hard drives and get it set up for testing.


The DS408 ships without drives, so you are going to need to install at least one 3.5” SATA drive of any size up to 1.5TB to get started. That means it's time to open up the box and break out the screwdriver. Installing hard drives in the DS408 is no different than the process involved in building your own computer. There is a hard drive cage with slots for four drives and the drives are secured using screws (no quick-install mounting rail options). If you've never done this before, it's not as hard as it might sound and Synology provides a Quick Installation Guide on the included CD that will walk you through the entire process. Even experienced PC builders will want to take a look at the guide to make sure everything goes smoothly.

But nothing is going to happen until the case is open and to do that you start with the four thumb screws on the back cover. With the screws removed the back cover will drop down to reveal the inside of the case. The next step is to lift up the outer case covering and pull it toward you and remove it from the case shell. Now the entire hard drive cage is revealed along with the motherboard where the hard drive power and data connections need to be made.















Synology's Quick Installation Guide has you hook up the cables to the connections on the motherboard first, but I found it was easier to mount the hard drives first without any of the cables getting in the way. The drive cage is a no-frill steel affair with tabs punched out of the side that act to support the drives inside the cage. I found the fit to be fairly snug and you'll have to be careful when trying to slide the drives in. It took some effort to get a couple of the drives installed which involved some wiggling which is another reason I found it best to install the drives prior to hooking up the cables. You'll need to make sure to mount the drives with the connections facing the rear of the unit. Also make sure the drives are mounted with the metal cover facing up which will put the connections on the bottom of the drive when looking at it head on. Once the drives are inserted and have the mounting holes aligned, they need to be secured with two screws on each side using the mounting screws included in the accessories package.


With the hard drives securely mounted in the cage it's time to get the hooked up. That means a power cable and data cable for each drive you're installing. It's important to make sure you get the cables installed and hooked up to the drives in the proper order. If you've never done something like this before it's pretty easy but there are a couple of particulars to pay attention to. As shown in the photo of the motherboard below, the power connections are the white 4-pin headers on the left. The data cables go on the 4 black SATA connectors on the right. Looking at the cables included we see four 4-wire power cables with a white connector on one end. There are also four flat red SATA data cables, one of which is noticeably longer than the other three.


When hooking up the power cables you will need to pay attention to the orientation of the white plugs on the cables prior to connecting them to the 4-pin headers on the motherboard. The Quick Installation Guide has detailed photos and instructions. However, on our review unit, the power connectors on the motherboard were oriented in the opposite direction from that shown in the guide. Also the guide says the connections are labeled on the motherboard as to which connector goes to which drive starting with HDD1 at the top and going to HDD4 at the bottom. On the review unit mother board the labels were labeled differently, using CN9-CN12 instead. Fortunately, there is a large graphic on top of the drive cage detailing which power cord is for which drive. Also, because the power connections were reversed from what was shown on the Quick Installation Guide, you need to make sure the white connector on the power cable is properly oriented. The power cable connectors have a indented slot on one side and on the other side is a small key that fits into a hole on the motherboard connector that locks it into place. Make sure the slotted side faces away from the vertical tab on the motherboard connector. On the review unit that placed the red wire of the cable on the right-hand side.

As with the power connectors, the SATA data cable connections on the mother board were labeled differently from that in the Quick Installation Guide, using CN2-CN5. Once again, the graphic on the top of the hard drive cage is useful in determining the numbering sequence. SATA data cables can only be connected one way as they have an L-shaped slot that must mate correctly with its corresponding connector. The longest data cable must be used for the HDD 1 connection with the straight plug connected to the top right of four connectors on the motherboard. Connect the remaining three cables to the motherboard as per the graphic.


Installation is almost finished. The next step to connect the power and data cables to each hard drive. The longest red data cable connects to the top most hard drive (HDD 1) by pushing the right angle connector to the data connection on the hard drive which is the one on the right as shown in the label on the hard drive cage. The power connector goes to the connection on the left of the hard drive. You will need to rotate the connector 180 degrees so that is is upside down before connecting it to the hard drive as it is keyed and can only be inserted one way. Make the connections to the remaining drives, making sure to maintain the proper order when connecting the cables. You can make use of the the included cable ties to tidy things up a bit and keep the cables bundled together.


The final step is to insert the cable lock from the accessories bag to the outside of the rear door by inserting the tab into the square hole on the bottom left hand corner of the door. Now all we have to do is button things up by reinstalling the outer case shell and closing the rear door and securing it with the four thumbscrews we removed earlier. You'll notice the thumbscrew on the bottom left is now particularly difficult to secure because it has to pass through a hole on the cable lock you just installed. The added thickness of the plastic lock makes the screw almost too short to work. It would have been nice to have a screw that was about 1/8” longer to accommodate the lock.

Once the cover has been secured, you'll need to connect the AC power adapter to the unit and plug it into the wall and connect the RJ-45 LAN cable to the unit and connect the other end to a router or switch. That wraps up the installation process and now we're ready to move on to configuring the DS408.


Once you have the hard drives installed it's time for the initial configuration of the the DS408. You begin by inserting the installation CD in your optical drive and waiting for the Synology Installation start screen to appear. The next step is to click on “Set up the Synology Server” option to start the discovery and initial setup process. After a few seconds, the software should locate the NAS server and briefly display a screen showing the default server name and the IP address of the unit assigned by your DHCP server. Since this is the first time through the setup process the system will detect this and pop up the Setup Wizard screen. This will allow you to load software from the installation CD and specify whether to do a one-click setup or follow step-by-step instructions. I chose the step-by-step to get a look at all of the options. The software is a .PAT file located on the CD and was automatically found by the system. You could take a moment to check check Synology's support web site for updates and use the Browse button to select the location of a more recent version you downloaded if one is available.











The wizard steps you through all of the steps to configure the basic setting needed. The default name of the server is 'DiskStation' and is used to identify and access the unit on the network. The unit comes configured with a administrator account with no password. The “Create password” page allows to to create a strong password (up to 127 characters) for the administrator login. It's a very good idea to go ahead and change the password at this time to keep others from changing settings on the unit. The server can use DHCP to obtain an IP address from a router or you can manually assign a fixed IP address to the unit. If you choose a fixed IP address the system first checks for any conflicts before assigning that address to the DS408.




There are just a few more quick steps to finish the setup wizard. The next step is to set the time zone and date/time for the DS408. That was the last of the data entry steps and once you have reviewed your settings and clicked the Finish button you are asked to confirm before the settings are saved to disk. Clicking the Yes button begins the process of applying the settings to the server and the creation of the system and data partitions on the disks. This process takes a few minutes depending on the number and size of your hard drives. Once the process is finished, you'll get a success message and, after clicking the OK button, you'll be automatically redirected to the login page of the Web UI.




We've just set the basics on the server but it's not ready to use until we create a volume on it which we need to do by using the Web UI.


Managing the DS408 is done through a web-based user interface known as Synology Disk Station Manager 2.0. DSM 2.0 is an AJAX (Asynchronous JavaScript And XML) management UI that provides a richer web interface akin to running a Windows application on the desktop. It is through this interface that you access and manage all aspects of the DS408. You can reach the login page of the management screen by pointing your browser to where '' is the IP address of the Disk Station. If you chose not to assign it a fixed address during in the setup wizard then you can use http://DiskStation:5000. If you changed the server name during setup you would use that name in place of 'DiskStation' in the URL. We'll look at the Web UI and all of its features in greater detail later.

We need to finish the initial configuration of the server by creating a volume. This means we need to have the system configure the drives and get them ready for to be used for storage. A volume is simply a way of referring to the space on a drive or set of drives. If you recall, at the end of the Setup Wizard process, the wizard automatically launched the login screen for the Web UI. Since this is the first time through we have to use the system administrator account and you'll need to supply the password you choose during the setup process described earlier. If you didn't change the password then leave it blank, which is the default. Once you have successfully logged in you see the main Disk Station Manager screen and along the left hand side you'll see a tree structure that list the components. You'll need to make sure the Storage node is fully expanded by clicking on the '+' next to it. Beneath that you need to click on 'Volume' to bring up the screen where you'll begin the volume creation process. You'll notice the screen is essentially blank as this is our first time to create a volume. The only option available to you is the Create option and once you click on that you start the Volume Creation Wizard that will walk you through the steps needed to create a new volume.






The first step in the volume creation process is to specify which disks to include in the volume. Before you make a choice you need to consider which volume type you will be using. The DS408 supports five different hard drive configurations: Basic (each hard drive is configured as a separate volume), RAID 0 (also known as striping where two identical drives are set up as one larger drive), RAID 1 (also known as mirroring where one drive maintains a copy of the other drive), RAID 5 (uses striping similar to RAID 0 but also provides redundancy for data protection) and RAID 6 (similar to RAID 5 but provides protection against 2 drives in the set failing). The pros and cons of each type of setup are outside the scope of our review but a concise explanation can be found in The Official OCC RAID Guide, Version 2.0. Basic volume types can only make use of a single drive, while RAID 1 volume types must consist of two drives. RAID 0 volumes can be configured using two or more drives and RAID 5 and Raid 6 volumes must contain three or more. In our example I'll be creating a RAID 5 volume type so I selected all four drives by highlighting them and then acknowledged the warning about all the data being erased. On the next page I chose RAID 5 as the volume type. The final choice to make prior to the actual volume creation process is to select how the drives will be examined prior to creating the volume. A complete consistency will examine each drive for bad sectors and remap them before the volume is built. This process could take up to several hours depending on the number and size of the drives. If the drives are new or have never been checked for bad sectors this is the preferred choice. A rapid check is similar to during a quick format in Windows. The danger being that if a bad sector on the disk is encountered later it could cause a volume crash.


After you have made your choices and press the Next button you'll get a chance to confirm your choices. In our example we'll be doing a rapid check just to save a little bit of time. Another Next button click starts the volume creation process. This can be a several hour process as mentioned earlier, so this would be a good time to go do something else. When the volume creation process is finished, you should see the volume information with a status of 'Normal' as shown in the final screen shot.




Now that we have the volume created, it's time to look at some of the additional features and configuration options available on the DS408.


As mentioned in the section on volume creation, the management of the DS408 is done through an AJAX Web UI called Disk Station Manager. The unit was tested with version 2.0, although Synology has released a beta 2.1 version since I began testing the unit. The user interface is divided into two panes. On the left side you have all the major categories arranged as folders in a tree structure similar to Windows Explorer. The right hand pane takes up most of the screen real estate and can be configured in one of two views. The first view is Wizard Mode that allows you quick access to some of the more common features. You can also set it to Complete Mode which displays all of the features broken out by major category with each individual feature represented. This complete list of features extends past a single screen, requiring you to scroll down to set all of them. You'll also notice in this mode there is a one-to-one correspondence to the directory tree shown on the left.  You'll also notice in this mode there is a one-to-one correspondence to the directory tree shown on the left. In the upper left hand corner you also notice options to return to the home page as well as an option to restart or shutdown the server.






The management features are broken down into seven main categories:
Information – this section allows you to view the status of the unit including general and network settings and overall health of the system and hard drives. You can also use this section to view any of the various logs maintained by the unit.
System – included in this section are options to set the detailed network settings, language used for the display and the time, time zone and network time protocol (NTP) server. Other options include setting up e-mail notifications, power settings, update the firmware and restore the unit's settings.
Privileges – here is where you can create users, groups and network shares and assign rights to folders as well as set user disk space quotas.
Storage – this is where you can check on the health of your disk drives using SMART monitoring as well as create, delete and repair volumes.
Network Services – the DS408 provides various services that can be enabled in this section including FTP, iTunes service, multimedia UPnP support and other Web services such as enabling the Web server and photo sharing capabilities.
Backup – these options are for backing up the system configuration and creating local and network backup jobs.
External Devices – these are all features associated with devices connected via the external USB ports including flash drives, printers and uninterruptible power supplies (UPS).


The Information section contains three subsections where you can get information on the current status of the DS408 as well as check any items in one of the various logs maintained by the system. There are no user-configurable items on this page.

The Status subsection displays basic information on the health and status of the DS408 and the physical drives and any volumes you have created. Various information is displayed in three panes broken out by 'Basic information', 'Network', 'Time', 'Hard Disks' and 'USB device'.

In the 'Basic information' area you'll find information on the server itself including the name, serial number, amount of physical memory installed, system temperature and amount of disk space used/available on the volume(s).

The 'Network' area details basic network information pertaining to the settings you supplied including IP address, subnet mask, DNS server address and workgroup name.

In additional to the actual time set on the system, you can view time parameters such as time zone and NTP time server name if yo have one defined.

You can also check on some of the SMART information reported on the physical such as model number, temperature, size, status and which volume the disk is included inalong with information on any USB devices connected to the DS408.


The DS408 maintains several logs of events. The systems log monitors both normal and abnormal activity and presents them in a easy-to-read format with the most recent events at the top of the page. Information includes the event time, user name and event description. The display can be sorted by any column by simply clicking on the column heading. You also have the option of clearing the log or saving the log to an HTML file for archiving or research purposes.

Logs are organized into six different categories. In addition to the System log, the DS408 maintains logs for Connection, Current connection, FTP file transfers, Backup and Network Backup events.


There is also an About page that displays various information concerning copyright and trademark notice information. Next up we'll check out some of the System configuration options on the DS408.



The system section contains setup options including network and time settings specified during the initial setup process, choosing the language to use and defining PPPoE settings. This section also has options for saving and restoring system settings, upgrading the firmware and establishing e-mail notifications.

The Network subsection shows the server name and LAN address information we entered during the initial setup process using the setup wizard. You can change the information on this page without having to rerun the setup process. If you change the IP address the system will log you out and back in using the new address as the target URL. One thing new you'll notice on this page is the ability to change the jumbo frames setting which was not available using the setup wizard. The default setting is for jumbo frames to be disabled, resulting in a maximum transmission unit (MTU) size of 1500 bytes. That setting should be sufficient for most networks and for Internet access. However, if you are using a Gigabit network connection you can enable jumbo frames and vary the MTU size from 1500 to 9000 bytes assuming the rest of your network components have similar capabilities. There is no option to manually set the link speed and it will automatically detect the proper speed based on the speed of your network and is capable of 1000/100/10 speed connections.

The DS408 supports 15 different languages for the display and email notifications. You can choose to set the display language based on the browser default or choose the language from the drop down list. Included in the list are four for which our test machine did not have the proper character sets installed - Japanese, Korean, Traditional Chinese and Simplified Chinese - which is why you see the odd characters displayed in the screen shot.

Point-to-Point Protocol over Ethernet is a protocol commonly used by DSL subscribers to connect to their ISP and establish a shared Internet connection. The DS408 provides a screen to enable this functionality and set the user name and password as provided by the DSL provider.



The Time subsection allows you to set the time parameters on the DS408 including the actual time and time zone. During the initial setup process we set both of these parameters, however the actual date and time were set manually. This section allows you to set the data and time manually or you can choose to specify a Network Time Protocol (NTP) server either by entering a URL manually or choosing one of the ones from the preconfigured drop down list. You can choose to have the unit synchronize the time either daily, weekly or monthly.

The DS408 can send e-mail notifications to two separate addresses whenever an important event occurs according to the user's guide. What constitutes an “important event” is not spelled out however. You can specify your SMTP server URL and the port to use as well as whether or not to use a secure connection and the login credentials needed for authentication. You can also choose whether to send a test e-mail upon saving the settings. The test message came through with the subject “DiskStation - Synology Disk Station”. The results of the test message attempt are logged in the System log in case there are any issues.

I was curious as to what types of events would trigger a notification so I e-mailed Synology technical support and got a response back within a day. I almost wished I hadn't asked as the list is rather comprehensive:

If something happens on the DS408 it will let you know about it!


The DS408 offers several power setting options to make sure your unit is available when you need it as well as reducing power consumption when the disks are not being used. There is an option to automatically restart the server after a power failure as well as the ability to spin the disks down after a certain period of inactivity. That period can range from 10 minutes to 5 hours. The unit can also be scheduled to turn on and off and on a set schedule. This would allow you to turn the unit off at night and on weekends when it is not being used and then restart it the following morning. The schedule offers enough flexibility to choose daily, weekdays, weekends or specific days of the week. During testing I set it up to power down every day at 23:55 and restart at 07:00 which I could confirm by checking the system log for shut down and restart information.


Restore Defaults
The Restore Defaults subsection allow you to reset the DS408 either by reformatting the hard drives and maintaining your current settings or reformatting the drives and reverting back to the the factory default settings. If you have set up a MySQL database for use with the Web Station feature you can either reset the password or delete the database altogether.

Firmware Update
Synology makes it easy to update the firmware on the DS408 whenever a new version is released. After downloading the file from the Synology web site. It even provides a convenient link back to the web site. Once you have the file downloaded, you can simply browse to the file location and press the OK button to update the firmware. According to the user's manual, updating the firmware will not affect the data on the server, but it's always a good idea to back up your data beforehand. It should be noted that you can not downgrade the firmware. Once you upgrade, you can only install a newer version, there's no reverting back to a previous version.


Package Management
The DS408 includes a Package Management option which seems to be a virtually undocumented feature. There's no mention of this option in the user's guide. In the Linux world, package management tools are designed to facilitate locating, installing and uninstalling precompiled software applications, or packages, for your system. So just what packages are available to be installed on the DS408? The only package available on Synology's support web site is for the Logitech SqueezeCenter. SqueezeCenter is Open Source software designed to stream your music collection over your local network or the Internet to a software player such as iTunes or Winamp.

Clicking on the Install icon in the upper left hand corner of the page launches the Package Installation Wizard which walks you through the process of installing the software package. I downloaded the SqueezeCenter software from Synology's site, which was a 19MB compressed file (.zip format). Once the download is complete you need to extract the file to a local drive or to the DS408 itself. The package has a .spk file extension. Launching the installation wizard enable to install the software package in just a few steps and is fairly quick and painless. You will need to browse to the folder containing the .spk file you extracted earlier and click the Upload button.


A couple of more mouse clicks to verify you want to install the software and you're done. In a matter of just a couple of minutes you'll get a confirmation message that the installation was successful and the software is ready to use. Back in the Package Management window you'll see the SqueezeCenter software listed and the Uninstall and Run icons are now enabled. Clicking Run kicks off the service. You can also use this window to stop the service and even uninstall the package if you want to.


Once you figure out what the feature is for, it's very straight forward and easy to use and no documentation is needed. However, it would have been nice to see some mention of its intended use somewhere in the user's guide. You can get more information on SqueezeCenter, including documentation, at



Once you established the basic operating parameters and created a volume, the next step in the process is to create users, groups and shares. Planning ahead will allow you to define which users get access to particular folders on the DS408 and creating a well-thought out folder structure ensures users get access to the data they need without granting access to data they don't need or only need read access to, for example.

The User subsection allows you to create, delete and maintain users on the system. This is also where you can change the default password on the admin account and set disk space quotas for users. You start out by clicking on the Create User button which brings up a dialog where you can enter the basic information on each user including user name, description, e-mail address and password. Moving to the 'User groups' tab lets you assign the new user to different groups. If you haven't created groups yet, you can add the member later once you gone through the exercise of creating groups. Each new member is automatically added to the 'users' group by default. Finally you can assign a quota to each user to determine how much storage space to allocate to each user. Space can be allocated in terms of MB or GB based on the drop down list. A value of '0' means no quota is assigned and the user has unlimited disk space. Quotas can only be assigned at the user level, there is no option to assign quotas to groups.





Once the user has been set up, the DS408 will generate an e-mail to the user with the name and password (assuming you set up the e-mail parameters as described earlier in the Notification section). The user is also given the URL of the DS408 where he/she can log in under their account to change the account description, password and e-mail address. The user can also monitor disk space usage. This is an important feature as there is no e-mail notification generated for exceeding quotas. In Windows, the users will simply get disk space full error messages once the limit has been reached.

You can perform additional maintenance operations on users using the Edit and Delete icons to change user information including description and password, disable user accounts and delete the user account completely. The fourth and final feature, Import Users, allows you to import a list of users instead of having to create them one at a time. The user's manual contains no information on this feature, but fortunately you can use the context-sensitive help to find out the format needed. Clicking on the '?' icon on the upper right corner of the page brings up information on the User section and you can scroll down to find out more about the Import Users function.



A Group is used to aggregate a set of users into a common entity. That way you can assigned rights to one group and have the rights automatically apply to every user in the group. This makes assigning and tracking rights and privileges much easier and more efficient. If you are diligent at only assigning rights to groups, then finding out which users has access to a folder simply means checking for group access rather than having to look at each individual user. This may not seem to be a big deal, but for business environments where there may be multiple users, using groups is virtually mandatory.

As with the User subsection, you can Create, Edit and Delete groups. The system comes with a default 'users' group which automatically contains all users. Clicking on the Create button allows you to create a group by assigning a group name and description. Once the group has been created, the Edit Members icon is enabled and you can add and remove members from the group. Clicking the Add icon brings up a list of members which you can choose by highlighting and clicking OK.




Shared Folder

Along with adding additional storage space, one of the main features of a NAS server is the ability to create storage space that is accessible by multiple users across the network. The way you do this is by creating shared folders and granting access rights to groups and users. Along with Create, Edit and Delete functions, you also have a Privileges option and you can also set up Network File System (NFS) parameters if you have systems on the network using the NFS protocol.

Clicking on the Create button brings up a dialog for you to provide a name and description for your folder. You can also choose to hide the shared folder to keep it from being visible in “My Network Places”. This just means it won't be visible to the public, just like creating a share in Windows with a '$' suffix. The system is kind enough to warn you if the folder name is too long for Windows 98 users (yes, there are still some lurking out there somewhere). Shared folders are created at the root level of the volume, meaning you can not create shares as a subfolder of an existing share. The second step in the folder creation process is to assign privileges as the default is for all users to have read/write access.




Under the Advanced Privileges tab you can choose to make the folder write only for use as an upload folder under FTP or the Synology File Station. Clicking the OK button will generate a warning message because it detected a conflict in the user privileges. Because the OCCTestUser1 account is a member of both the OCCTestGroup and the default users group, and we assigned different rights to both groups, the system has to make a ruling on which rights to use. In this case No access trumps Read/Write so we would have to remove the OCCTestUser1 from the default users group in order for the user to have the intended access.


Choosing the NFS Privileges tab will start the NFS service if you haven't already done so and then you can specify the parameters as needed.


Let's move on to the Storage management area to look at some of the features we didn't get to see during the initial setup.



We already visited the Storage subsection during the initial setup process when we created the volume. Besides creating a volume you can also make changes to existing volumes by repairing volumes with a failed drive, add larger capacity drives and expand an existing volume or add additional drives to an existing RAID 5 or RAID 6 array. You can also upgrade from a single drive to a RAID 1 array. To look at these features I configured the DS408 using a 3-disk RAID 5 array, leaving the fourth drive unassigned in order to test out the Add Disk functionality.

HDD Management

The HDD management feature is used to enable any write cache support which can improve disk I/O performance as long as it is supported by the hard drive.







When we set up the initial volume, all we did was use use the Create option so let's spend some time looking at what else is available.

Get Info – This feature gives up the basic information on the volume including name, type and status. It also reports on the size and available remaining space. In our example where only three of the four drives were included in the array, with the fourth drives unassigned the system also alerts us to the fact that we could add it to the existing RAID 5 array which we will do later.

Create - As we saw in the initial setup, the Create option is used to create a volume on one or more of the installed disks. The DDS408 supports Basic (single drive), RAID 0, RAID 1, RAID 5 and RAID 6 volumes. The current version of Disk Station Manager (2.0) does not support JBOD volumes, although that feature is present in the next version which is currently in beta testing.


Repair – There are two scenarios where you can use the repair function. The first is if a hard drive in a RAID 1, RAID 5 or RAID 6 array fails. You can replace the failed drive and use the Repair feature to rebuild the array. The second scenario is if you want to replace existing drives with ones with greater capacity. In this case you would replace each drive, one at a time, using the Repair feature after each new drive is installed until all drives have been replaced and repaired. Since the array has to be rebuilt multiple times this would take several hours to accomplish.

After a drive in an array has been replaced, clicking on the Repair icon launches the Volume Repair Wizard that will walk you through the process of repairing the array. The first step is to choose a drive to add back into the array. My simulated failure was on drive 1, but I could have also used the unallocated drive 4 as shown in the screen shot. After highlighting drive 1 and pressing Next, you get a warning that all the data on the new drive will be erased and offered a chance to halt the process. You'll get a second chance to review everything on the Confirm Settings dialog before starting the repair process.


The process of repairing and rebuilding the array is lengthy as it has to first repair the array and then check the parity consistency used in RAID 5 arrays. The process would be identical for repairing RAID 1 and RAID 6 arrays.


Remove – The Remove feature is pretty self-explanatory as it allows you to remove, or delete, a volume. Doing so will obviously cause you to lose all data on the array, so this option should be used with caution. As with the other options here, clicking the Remove button launches a wizard that walks you through all the steps. It will also show you all the shared folders on the volume in case you need reminding of the data you are about to lose. While you will lose any shared folders on the volume, users and groups you created remain intact.


Expand – The DS408 enables you to replace existing drives in a volume with drives of equal or larger capacity. For RAID 1, RAID 5 and RAID 6 volumes this means replacing a single drive, repairing the volume and then repeating the process for each drive used in the array. This is a rather lengthy process but can be done without shutting down the server (using the hot swap capability) or losing access to your data. However, when you are done you are left with a volume of the same size as before, just on larger drives. After replacing and repairing all the drives, you can use the Expand function to grow the volume size to the full capacity offered by the larger drives. Unfortunately, I didn't have a complete set of larger drives on hand to demonstrate this feature.

Upgrade – The Upgrade feature allows you to upgrade a basic volume using a single drive to a RAID 1 volume and is enabled only if you have a second drive available. As you might expect, clicking on the Expand icon launches another Wizard that takes you through the process. Once you have chosen a disk from the list it will warn you about data being erased on the second drive you are adding. After you have confirmed the settings, clicking Next will add the disk to the array and the DS408 begins the process of synchronizing the two drives.





Add Disk – Another way to grow a volume is to add a disk to an existing three-drive RAID 5 or RAID 6 volume. The Add Disk feature is enabled for RAID 5/RAID 6 volumes when there is an unallocated drive available. The Add Disk Wizard follows the same format as the previous wizards, allowing you to choose a disk (since RAID 5/RAID 6 requires a minimum of three disks, there is only one to choose from), issues the requisite warning about erasing data on the new drive, confirms the setting and begins the process of adding the new disk to the array.


Beep Off - No, the DS408 is not trying to be flippant and tell you what to do. This option allows you to turn off the warning beeps when a hard drive failure occurs.


This subsection offers the ability to view and monitor the health and status of the hard drives in the DS408 using Self-Monitoring Analysis and Reporting Technology (S.M.A.R.T.). S.M.A.R.T. is an industry standard supported by major drive manufacturers and is a way to get detailed information on factors affecting your hard drives. While not fool proof, it can be useful as an early-warning system prior to a hard drive failing. The DS408 offers various ways to view the information including overall temperature and status of each installed drive. You can double click on a drive in the list to get model number, serial number and firmware version information. The S.M.A.R.T. Info icon offers detailed reports on each individual disk. There is also an option to run short and extended tests on each drive.




That was a lot of information to go through and now it's time to move on to see what else the DS408 offers in the way of additional network capabilities.


Network Services:

The Network Services section allow you to set some of the network-related settings on the DS408, but it is mainly used to enable additional services on the server. You can use it to share music and media files across the network, act as an iTunes server, set up a FTP server and more. Additionally, Synology has several services it classifies as Stations that allow you to use the DS408 to act as a audio player, share photos over the Internet, manage file via a web browser and capture video from IP cameras. It even has the capability of being run as a web server where you can host multiple web sites with PHP/MySQL support.

Win/Mac OS

Under the Win/Mac OS subsection you can set up the DS408 to work on Windows workgroups by specifying the workgroup name. The server can also be integrated into a Windows domain through its support of Active Directory service. You can specify the domain name along with other domain-specific items such as the Kerberos authentication server address and the WINS server address. You can set up a recycle bin on the server to hold deleted files. When you enable this feature, the system creates a '#recycle' folder under the root directory. For Apple computer user there is the option to enable AppleTalk and define which zone to join.


Enabling the DS408 to function as an FTP server and all of the various settings are controlled in this subsection. You can use the default Port 21 or another port number of your choosing. The system uses a default data port range of 55536-55663 but you can specify a different range from 1025 to 65535. The range can contain up to 128 ports. The port settings are critical because you will need to know the port number and ranges in order to set up port forwarding on your router. You can also limit the number of concurrent connections, enable logging and set bandwidth restrictions. Other security-related features include only allowing SSL/TLS connections and specifying IP addresses to block.






Web Services

The Web Services subsections contains a lot of features that allow you to manage your DS408 over the Internet using a secure connection as well as several web services such as photo sharing, hosting your own web site, enabling the browser-based file manager and the playing audio files using the included player.

HTTP Service Options

You can set up a secure connection to the DS408 so that you can connect via secure encrypted connection. This will allow you to access the various manage UI from outside the network. It's also useful if you are using the DS408 to host a web site and need a secure connection for a shopping cart setup. You can also specify an alternative port for the HTTP connection, a handy feature if your ISP blocks the standard port 80. You will need a security certificate in order to use this feature.


Web Applications

Here's where things get interesting in terms of some of the extra features offered by the DS408 for sharing various forms of content across the network and over the Web. The four different features are Photo Station, Web Station, File Station and Audio Station. As you can infer from the names, they are uses for sharing photographs, running a web site, managing files and streaming audio.


Photo Station 3 – Photo Station 3 is an online photo album that allows you to share photos and videos over the Internet. Enabling this feature automatically creates a /photo folder under the root directory. In order to use the Photo Station sharing feature, photos must be organized in subfolders under the /photo folder. Visual media files placed directly in the /photo folder without a subfolder will not be displayed. The DS408 provides a link on the setup page to a tutorial on how to set the system up and make it available over the Internet. If you don't have a static IP address, you can use a dynamic DNS service and point your browser to http://DDNS_hostname/photo/ where 'DDNS_hostname' is the name provided by the DDNS service. Requests are treated as http requests, so you'll need to forward port 80 on your router to the internal IP address of the DS408. Once connected, users can view the pictures as thumbnails and click on the files for a larger image or choose to view all items in a folder as a slide show.

Another feature tucked in with Photo Station 3 is the ability to create and publish your own blog. You can post blog entries and they'll be accessible through the same address as the shared photos – there's a link to the blog in the top right hand corner. The blog can be customized for layout and content. Users can post comments, search content and look at archives.




Web Station – You can host your own web site on the DS408 with the built-in Apache web server and support for MySQL and PHP. Enabling this feature automatically creates a /web share under the root directory and this is where you would upload your web pages. You can host up to 30 different web sites by creating virtual hosts that map to different hone pages. As with Photo Station, there is a link to a short tutorial on how to set this up. However, it is not a tutorial on how to build a web site. You can install PHP-based tools like phpMyAdmin to administer the MySQL database.

File Station - File Station is a web-based file organizer where users can access and manage files stored on the server remotely using a web browser. Using File Station is much more efficient, especially when moving or deleting files as the files require no routing through your computer as they would if you were using Windows Explorer.

Audio Station – Audio Station is a web-based music organizer and player where you can organize your music and play it on client PCs using the included audio player. Enabling this feature creates a /music shared folder under the root directory. You can use the organizer to create playlists and you can hook up a pair of USB speakers to the DS408 and play music directly from the DS408.



Once you have enabled the File Station and Audio Station, you'll notice two new icons on the Disk Station Manager page for File Station and Audio station. Clicking on these icons take you directly to the respective pages. From the web log in page you'll see new tabs for each of the stations so you can reach each, either as an administrator or user, without having to go through the Management tab.




You can use the DS408 as a repository for all your multimedia files and stream them to any UPnP enabled player. After checking the box to enable plug and play support, you can change the settings to match what is needed by the media payer.


In addition to the Audio Station and streaming media to a digital media adapter, you can also set up the DS408 to act as an iTunes server by simply clicking on a check box. The iTunes server name defaults to 'DiskStation' and you can change that to a name of your choosing. You can also require users to enter a password before they can see the shared music stored on the server.


Unless you have a static IP address provided by your ISP, accessing the DS408 from the Internet can be tricky as a dynamic address can be changed by your provider at any time. Using a dynamic domain name service (DDNS) can help solve this problem by assigning a fixed name and tracking the actual IP address to match it with the name. The DS408 supports several of these providers. Once you have registered with the service provider of your choice, you can enter your host name and login credentials and the DS408 will notify the DDNS provider anytime your IP address changes. This way you can always access the DS408 using the DDNS host name.

Surveillance Station

Surveillance Station is another web application provided by Disk Station Manager. With this application you can manage IP cameras on a LAN, and record video with them. Enabling the Surveillance Station will create the default share, /surveillance under the root directory to store the recorded video footage. I don't have any IP cameras to test with, but the Surveillance Station app will let you easily add and set up camera, monitor cameras through a live view assign privileges. The application also maintains its own log of events. This is certainly a handy application for users such a s small business owners that need a convenient and easy way to set up video cameras as part of a security system.




Download Station

We come to the final web application offered by the DS408. Download Station is used to manage downloads, either through scheduled FTP tasks, BitTorrent or eMule. After enabling Download Station, you can either use the web application or install the Download Redirector software onto a local PC from the install CD. You can create a task and specify a file name, such as a torrent file, or a URL for FTP downloads. If you're logged in under the admin account you can specify the specific settings for different types of downloads such as the order, number of simultaneous FTP connections or specify the setting for download NZB files from a news server. Download Station also includes a BitTorrent manager you can for downloading torrent files and you have a range of options you can set including minimum and maximum download rates, port ranges and how long to continue seeding the file once the download is complete. Initial set up is straight forward and requires only specifying a default download destination. Download settings default to a specific port range and you should not have to modify them. Download/upload speeds default to unlimited and the download file will be seeded until the download is completed. You can adjust those settings as needed and will apply to all users. As an administrator you also specify the settings required for using eMule. Logging in on a non-administrator account you can set up downloads, but not modify any of the settings.


Creating a download task is simply a matter of specifying the file name such as that of a torrent metadata file or an FTP site URL and clicking the Create button. The download will begin immediately unless you have set up a schedule under the original setup page. You can monitor the download progress from the main task page or highligh the task and click Get Info for more detailed information on the file and transfer. You can also use the icons on the download page to pause, resume and delete download tasks.




The DS408 runs a version of the Linux operating system. For users comfortable with the command line interface in Linux that need access not provided through the web GUI, you can enable access through Telnet or secure shell (SSH) and then access the operating system.


There's not much to this subsection, just a single check box to enable the DS408 to be accessed by systems using the Network File System Protocol(NFS).



After you have enabled Surveillance Station and Download Station you'll notice two new icons have joined the ones for File and Audio Stations at the top right corner of the web UI. You'll also notice a new look to the login page with tabs for Surveillance and Download Station. The Web Station and Photo Station tabs have shifted to a second page you can access using the little white arrow off to the right.


That concludes our tour of the services and features available under the Network Services folder. Now let's check out the backup features on the DS408.



The DS408 provides the capability to back up the data on the several to different targets. This includes local backups to USB drives attached to the DS408 or to a local share on the DS408 itself. Your can also back up the unit to over the network to another Synology server or to any rsync-enabled server.

Configuration Backup

After you have spent a great deal of time configuring the server, creating users and groups and assigning shares, it would be nice to know all your hard work is safe. With Configuration Backup you can store those settings to a file separate from the DS408 for added safety. You can also use this feature to restore previously saved settings.












Local Backup

The Local Backup option allows you to back up data to a shared folder on the DS408 or to an external drive connected via the USB port. Clicking the Create icon launches the Local Backup Wizard that will walk you through the steps necessary to create a backup task. First you need to chose a name for the task and the shared folder(s) to back up. Since shared folders can only be defined at the root directory level, you can't drill down to specify specific subfolders.




After choosing the source folder, the next step is to specify a target folder. In this example we are using a local shared folder. The backup task will create a /LocalBackup folder on the target drive to store the files. You can create a basic schedule choosing a single day and time or opt for a more advanced scheduling function for daily or specific days of the week. Once everything is set up and confirmed, the job is ready to roll on the scheduled date/time.




The system will perform a full backup the first time the job is run. That means all files in the shared folder will be backed up. Subsequent backups will be incremental, backing up only those files that have changed since the previous backup. You can use the Get Info icon to look at details of the job and you also have the option to edit and delete scheduled tasks. Another useful feature is the Backup Now option that will allow you to run a task immediately without having to wait for the scheduled kickoff time.



Network Backup

The DS408 provides the capability to back up to another Synology server or other rsync-enabled server on the network or over the Internet. Rsync is an application for Unix/Linux systems that allows you to synchronize files between the two systems. The process is similar to the Local Backup process except clicking on the Create icon launches the Network Backup Wizard. Since we covered the basics in the section above, we'll just touch on some of the differences here. Instead of choosing a local drive, you need to tell the system whether you're using another Synology server or a rsync-compatible server. You can also choose to have the data encrypted before it is transferred. Once you specify the server address and login credential information, the process is pretty much the same as with the local backup. You'll also notice there is an additional icon, Network Restoration, that launches, you guessed it, the Backup Restoration Wizard which can be used to recover files backed up using this method. This becomes necessary if the files were encrypted during the original backup task.



Network Backup Service

As mentioned earlier, rsync allows you to synchronize files between two systems and you can use the DS408 as a backup target as well by enabling the Network Backup Service feature.


This just about wraps up the configuration settings. All we have left to do is check out what those USB ports on the back of the DS408 are for.


External Devices:

The Ds408 comes equipped with two USB 2.0 ports on the rear of the device that can be used to connect external devices such as hard drives or flash drives or a printer. You can also connect an uninterruptible power supply through one of the USB ports to monitor power state and amount of battery power available in the event of a power loss.

USB Disk

You can connect a USB disk, whether it is a hard drive or flash drive to one of the ports. The DS408 will automatically detect the drive once it is plugged in and it becomes available as a shared folder called /usbshare1. You can click the Get Info icon to display details about the drive including the shared folder name.





USB drives can also be formatted directly from the unit using the FAT32 file system. You can then use the DS408 to administer the drive through the Privileges section and you can view and access the files from the File Station application. This is a convenient way to expand the storage capacity of the unit as well as a way to provide a separate repository for backing up the server.


USB Printer

The DS408 can act as a print server by connecting a USB printer to one of the ports. There is not set up or configuration involved. The server will automatically detect the printer once it is plugged in. You will need to install the appropriate drivers on each client PC using the printer.


In the UPS section you can set the DS408 to monitor power status by connecting a USB cable to an uninterruptible power supply (UPS). As long as the power cord to the DS408 is also plugged in to the UPS, the unit can be set to go into Safe Mode after a set period of time, from 1 to 60 minutes. Once power is restored the unit will reboot. This is a good way to avoid losing data or corrupting a RAID 5/6 array due to improper shutdown. I found I had to reboot the DS408 in order for it to properly recognize the UPS. Let's check out the features and specifications before moving on to the performance test results.


Let's check out the features and specifications before moving on to the performance test results.


 Model Number  DS408
 Hardware Version  N/A
 Firmware Version  DSM 2.0-0728
 External Interface  10/100/1000 Gigabit Ethernet Port
 Jumbo Frame Support  Up to 9000 bytes MTU
 Additional Ports  USB 2.0 x 2
 HDD Size  4 x 3.5" SATA Drives (not included)
 Drive Capacity  Up to 1.5TB drive
 CPU  800 MHz Freescale MPC8543
 Memory  512MB
 Flash  4MB
 IDE Controller  Marvell 88X7042
 NIC  Marvell 88E1118
 Linux 2.6.24
 File System  EXT3
 HDD Configuration  RAID 0, RAID 1, RAID 5, RAID 6
 Power Supply  External adapter
 Cooling  80mm fan
 Dimensions  184mm x 230mm x 168mm (WxDxH)
 Weight  2.23 kg - without drives
 OS Requirement  Windows 2000 onward
 Mac OS X 10.3 onward
 FCC Class B, CE Class B,
 BSMI Class B
 Warranty  2 year limited





Power Consumption(1)




Networking Protocols


Windows ADS Domain Integration




File System


File Sharing






UPnP Multimedia Service Support


iTunes Server Support


Audio Station Support


Photo Station 3 Support




RAID Management


Backup Solutions


3rd-Party Backup Support


Supported Clients


Printer Support(3)






Package Content


* The actual capacity will differ according to volume types.
(1) Measured with 4 Seagate 750GB ST3750640NS hard drives. The figures could vary on different environments.
(2) User can click and download the file, but not play it in Photo Station as compressed Flash video.
(3) For Mac users, DS408 supports PostScript USB printers only.
(4) The music can be streamed, but the metadata (ex:title, album) may not be indexed on the iTunes.
(5) FAN only. Measured at 2300~6200RPM, varied among models. More details about dB(A) value, check


All information courtesy of Synology @


To test the DS408 I will use SiSoft Sandra 2009 using the File System benchmarks. I will also use the Intel NAS Performance Toolkit (ver. 1.7) to gauge performance under several realistic usage scenarios. The tests will be conducted on all supported hard drive configurations with and without jumbo frames enabled. The DS408 will be connected directly to the Marvell PCI-E Gigabit Ethernet controller using a Category 6 Ethernet cable to eliminate any variations due to network components or traffic.




SiSoft Sandra is a diagnostic utility and synthetic benchmarking program. Sandra allows you to view your hardware at a higher level to be more helpful.










File System


Higher is Better



Lower is Better


The Intel NAS Performance Toolkit is a set of tools used to test and analyze file systems and enable direct comparison of the performance levels of different network attached storage devices. It utilizes a set of tests based on real world applications such as HD video playback and record, office productivity, photo album manipulation and file and directory copying. The toolkit uses a set of traces based on these applications and mimics the file system traffic generated and records the system response. In our evaluation, the toolkit was run in batch mode which runs the series of tests five times in succession and the median throughput value used to report the results. The hard drives were reconfigured and the DS408 was rebooted before each test was run. The RAID 0 array was created with four drives and the RAID 1 array contained 2 drives.




HD Video Playback (higher is better)

The HD Video Playback series of tests involve streaming a 720p HD video file using Windows Media Player and 256kb reads. The tests play either 1, 2 or 4 files simultaneously using different percentages of sequential reads (99.5% for the single file, 18.1% for the 2x HD Video Playback and 9.6% for the 4x HD Video Playback).






2x HD Video Playback (higher is better)



4x HD Video Playback (higher is better)



The DS408 seems made to stream video as it turns in its best results, breaking the 50MB/s barrier in the playback tests for the RAID 0 and RAID 5 setups. These tests play to the strengths of RAID 0 in reading data, but it is important to note that a RAID 5 setup can offer similar, if slightly lower speeds with the added protection from hard drive failure you don't get with RAID 0.

HD Video Record (higher is better)

This test writes a single 720p HD video file to the NAS device employing 99.9% sequential 256kb writes.



Recording a video caused throughput to drop below 40GB/s for RAID 0 and to the 26-36 MB/s range for the other configurations which is to be expected when writing files across the network. The write penalty is most evident in the RAID 5 and RAID 6 configurations due to the performance hit required in calculating and writing the parity data to the array.

HD Playback and Record  (higher is better)

The HD Video Playback and Record test combines the two previous tests and reads and writes a HD 720p video file simultaneously.



The DS408 still maintains decent throughput from 21-46 MB/s while simultaneously playing and recording a video. RAID 0 showed a performance boost, mainly due to the increased throughput as we saw on the playback tests. The write penalty associated with the other forms of RAID also becomes apparent. I would have expected the RAID 5 setup to do a little better here, although it did get a slight boost when enabling jumbo frames.

Content Creation  (higher is better)

This test simulates content creation on the NAS device such as might occur when rendering a video. There are 99 files used and is composed of 95% write operations with up to 64kb block sizes and consists of 39.1% sequential operations.



The content creation test starts to tax the DS408 with its large number of write operations. RAID 1 pulls ahead of the RAID 5/RAID 6 arrays since it doesn't have the burden of parity calculations.

Office Productivity  (higher is better)

The Office Productivity test is roughly evenly distributed between read and write operations using 607 small files consisting of 1kb and 4kb reads and mostly 1kb writes.



This test is where things start to get messy. With a large number of files and a heavy mix of read and write operations, the DS408 struggles, even with its 512MB of memory to buffer the write requests.

File Copy to NAS  (higher is better)

The File Copy test copies a single large file to the NAS unit using 100% sequential 64kb write operations.



Copying a single large file (1.4GB) brings us back to more normal performance numbers in the 26-37MB/s range with RAID 0 again taking the lead. Enabling jumbo frames provided a slight boost across the board, except for the RAID 0 configuration where it actually hindered performance.

File Copy From NAS

This test reads the single large (1.4GB) file from the File Copy test from the NAS using 64kb read operations.



Copying a single large file (1.4GB) brings us back to more normal performance numbers in the 26-37MB/s range with RAID 0 again taking the lead. Enabling jumbo frames provided a slight boost across the board, except for the RAID 0 configuration where it actually hindered performance.

Dir Copy to NAS  (higher is better)

This test copies a directory structure with 126 files to the NAS device using predominately 64kb writes but also includes a wide distribution under 16kb.



Reading the same single file back in the opposite direction we see the benefit of RAID 0 on performance. It also seems having more drives in the array helps as well for the multi-drive arrays.

Dir Copy From NAS  (higher is better)

This test copies the same directory structure of 126 files from the NAS device using 64kb reads.



Copying the test directory back to the host shows consistent performance across all setups with RAID 0 once again in the front of the pack.

Photo Album  (higher is better)

The Photo Album test simulates the viewing of 169 photo files of various sizes stored on the NAS and consists of 100% read operations.



Here we see the tightest performance grouping across all setups as the test does a series of reads of various sized photo files.

Some general observation we can make here show that RAID 0 doesn't offer a compelling benefit over RAID 5 in the majority of the tests. In my mind, the added risk of data loss from a hard drive failure using RAID 0 isn't justified when you have the option of using a RAID 5 array. I'd be willing give up the extra disk space for the increased level of protection. I also think it becomes apparent that enabling jumbo frames on the DS408 can't be justified as it doesn't offer enough of an advantage, and even hurts performance in some cases.


Now that we've taken a thorough look and run through some performance tests, it's time to check out the practical aspects of the DS408 in terms of operation.


The unit comes with a 80mm exhaust fan mounted in the center of the rear of the case. The fan guard is not overly restrictive and the fan spins fast enough for you to feel a decent amount of air movement, but not so fast as to be annoying in terms of noise. Synology claims a noise level of 26dB(A) for the fan. Cool air is provided by a pair of generously sized vents on the front of the case so the air flow should be across the motherboard and through the hard drive cage. Each drive has approximately ¼ inch spacing between them to allow for air movement.

During the testing the case didn't become warm. With the all steel shroud that forms the top and sides of the case you would be able to feel any increase in temperature. To test how well the system cools itself, I used the NAS performance Toolkit to run a full series of tests in a RAID 5 configuration and monitored the S.M.A.R.T. drive temperature readings as well as the system temperature reported on the Information Status page of the management UI. To monitor the interior case temperatures I inserted a digital temperature probe into the case with the probe positioned directly to the rear of the drives in the center of the case. Temperature readings were taken prior to the run with the hard drives spinning and then throughout the test.





  Idle Test
Ambient Room 19 C 19 C
System 41 C 46 C
Case Interior 28 C 30 C
S.M.A.R.T. Drive 1 31 C 35 C
S.M.A.R.T. Drive 2 30 C 34 C
S.M.A.R.T. Drive 1 30 C 33 C
S.M.A.R.T. Drive 1 29 C 31 C

You can see the highest temperature was reached by the drive at the top of the case, but the deltas were all quite respectable, even during the extended activity posed by the NAS performance testing.

Power Consumption:

One of the benefits of using a NAS server like the DS408 is lower power consumption. With the ability to put the drives in hibernate after a period of inactivity. You can set the drives to go into hibernation using the management UI. It's a simple matter of picking a setting from a drop down list and is easy to set. The unit can be set to hibernate the drives from 10 minutes to 5 hours.

I tested the various power usage levels of the DS408 at idle with the disks spinning but no activity, during a full test with read and write activity with the drives configured in RAID 5 and finally in power management mode with all drives set to power down after 10 minutes. All measurements were taken with a P3 International P4400 Kill A Watt power meter.

State Watts
Power Mgt. Mode N/A (fail)
Idle 41
RAID 5 Test 46-48

Even with heavy usage the DS408 manages to use less than 50 watts even in a four-drive RAID 5 array. However, over an extended period I only observed the system going into a low-power state on a single occasion, which is why the table shows N/A for the power management mode entry. I even disconnected the Ethernet cable to ensure there was no communication going on between the test computer and the unit. The one time I did manage to see it in a low-power mode the meter measured a miserly 20 watts. The rest of the time the unit was not being used the power usage stayed right at 41 watts.


RAID 1/5 Data Protection

As we've seen in the prior pages, the DS408 offers a lot more than just a few extra gigabytes of storage space. As important as that space is, the real importance is attached to the data it contains and that's where the redundancy provided by the different RAID structures. RAID is not a substitute for proper data backups, but it can help protect your data in case of a drive failure. To test the ability of the DS408 to survive and recover from the loss of a disk drive I simulated a failure in both RAID 1 and RAID 5 setups and tested each array for data safety and the ability to rebuild the array once the 'faulty' drive was replaced. The DS408 supports hot-swapping which means that drives can be removed and replaced without powering the unit down, leaving the unit operational. I simulated a failure by removing the power and SATA data cable from a drive while the unit was still powered on.

The first thing you notice is the loss of the HDD LED indicator on the front panel. Had this been an actual failure the LED would been an orange blinking state indicating which drive had gone bad. There is also an audible beeping alarm indicating a failure has occurred. If that is not enough of a warning, the system automatically sent out a e-mail alert telling you that “Volume 1 on DiskStation is in degraded mode. Please identify the cause of degradation and take corrective action.” When you log into the web UI, you are also alerted to the fact that the volume is in a degraded status and advises to repair the volume. I checked the data on the DS408 in both RAID 1 and RAID 5 setups and found everything to be intact and fully accessible. Next I hooked the drive back up while the DS408 was still powered up and went through the Repair process as described in the Configuration: Storage section earlier in the review. The repair process can be rather lengthy, but even during a repair I was able to access the data on the unit. Once the process is complete, the unit sent another e-mail notifying me the process had completed successfully. Checking the data again proved everything was back in order and no data was lost.


The next feature I want to cover also concerns data protection and that is the built-n backup features of the DS408. The configuration backup creates a file you can store elsewhere on the network. In case of any catastrophic loss you can use this file to restore the settings to the DS408 including users, groups and shares. This was simple to do and the backup to the unit went without a hitch. Setting up a local backup was also painless and I saw the scheduled task kick off on time and received daily e-mail notifications when the jobs completed. The only drawback to this type of backup is there is no data compression so the backup will consume the same amount of space as the original. I didn't have access to a separate rsync-enabled server to test the network backup. Synology also includes backup software on the install CD, Data Replicator3, that can be installed on local PCs to back up data to the DS408.

Other Features

During the review process I checked out all of the features and covered them in the configuration sections of the review. For the sake of brevity, I am not going to go into more detail here, but I would like to make some observations. I didn't test the Surveillance Station, create a web page under the Web Station or the UPnP multimedia features. I did try out all of the rest of the features, and trust me, it was a long list of items and a lot of work. I didn't have any issues, aside from not being able to get the unit to hibernate the drives even though it was configured to do so after 10 minutes, the minimum setting. All of the other features worked as designed and were easy to use.

Disk Station Manager 2.1 (Beta)

When we review products, we don't test using beta software/firmware. However, I did want to touch on the next release of the Disk Station Manger, version 2.1, as it incorporates some new features that I feel are worth mentioning. Just a few of the highlights include:

While the actual list of enhancements is much longer, I wanted to specifically mention the addition of JBOD support and more granular permissions as I feel they are sorely needed in a product of this caliber. The new enhancements also emphasize Synology's commitment to their product.


When I first started examining the DS408 I was impressed with the number of features it offered. For data storage it offers a RAID 0/1/5/6 which makes it ideal for both home and small office and workgroup environments. You can mount up to four hard drives for a maximum of 6TB of storage. The DS408 also offers volume expansion support where you can add additional drives to an existing RAID 5 array as well as the ability to replace existing drives with larger disks without losing data. The unit also offers an impressive list of multimedia functions for serving and sharing video and music files. Integrating all of these features can sometimes result in a patchwork of seemingly unrelated applications, but the DS408 avoids this with its Disk Station Manager user interface. I fell in love with its use of AJAX which gave the interface a rich application feel akin to a desktop application and enabled all the features to be integrated cleanly. The user interface is clean and well-laid out. It was very easy to use and did not suffer from the fractured English I've seen with other products. The user manual included on the install CD fell short of my expectations and I felt it was quite lacking at times and left me frustrated. Fortunately, the Disk Station Manager includes good context-based online help that can be accessed by simply clicking on a icon. I found it invaluable when I was trying to figure out some issues and it makes up for the shortcomings of the printed user guide. Performance was very good across most of the tests except in the Office Productivity test where it really struggled. I also had issues in getting the unit to hibernate the hard drives. Two other issues I raised in the review, lack of support for JBOD and only being able to create shares at the folder level, are being addressed in the next version of the software which is currently in beta testing. The unit is priced at a suggested price of $749.99 and street prices are very close to that. That puts it squarely in the small to medium-sized business market as all but the most serious home user will find that to be a major hurdle. Overall, I was very impressed with the feature set and found it offers just about everything for the multimedia enthusiast as well as the business user, and then some. I would have no hesitation in recommending the DS408 to anyone wanting to add professional-grade storage with excellent data protection to their network.

Note:  The day after I completed writing the review, but before it was published, I received notification from Synolgy of an upcoming price reduction (March 2009) that will lower the price of the DS408 from $749 to $699. This price reduction may well be in effect by the time you read this. Although that is a welcome reduction, I still believe the unit's price will represent a stumbling block for many as other 4-bay NAS units can be had for under $400.