The NAS can accommodate up to four 2.5-inch hard disk drives for storing user data and the integrated OS. You can view the model, serial number and firmware version of each HDD. Besides, you can view S.M.A.R.T. information (including temperature) and run a quick or full test described by that standard. Background processing of bad blocks is supported, but we used healthy HDDs and could not check out this issue.
Like most other NASes, the DS409slim allows building RAID arrays. It supports JBOD, RAID 0, 1, 5 and 6. If you install four disks, one of them can be a spare disk to be used automatically to restore the array when one of the main disks fails. There are only physical limitations as to the size and type of arrays. For example, you can have two disks in a mirror and two disks in a RAID0. The type and capacity of an array can be changed in some variants without losing data, which is useful for home users and allows upgrading the array without having to back up all the data to an external storage.
Besides RAID, the DS409slim supports iSCSI technology whose client is available in most of today’s OSes. Particularly, this technology can be used to create disk volumes for the OS itself and works via a program interface that emulates ordinary physical connections. For example, you can use any file system on an iSCSI volume or even work directly as with a block device. A total of 10 iSCSI volumes are supported simultaneously.
The disk space is allotted in the following way: 2.4GB for system purposes (about 400MB is occupied normally), 500MB for a swap file, and the rest is for data. The file system is ext3. You can read it from any Linux machine.
The DS409slim supports all modern network protocols for file access: SMB/CIFS, AFP, NFS and FTP. The NAS can be integrated into a domain on Windows networks. Besides, for this protocol you can enable a recycle bin for files deleted via network and choose a filename encoding for non-Unicode clients. MacOS X users can launch TimeMachine after specifying a shared folder on the NAS to be used by that backup utility. There are no settings for NFS. You can just turn this protocol on or off. FTP, on the contrary, abounds in settings like choosing ports (also for passive mode), turning encryption on/off, enabling Unicode support, and limiting the number of connections and speed. Thus, you can easily use FTP to securely access your files over the Internet.
The user database can be either local or on a Windows domain. Besides name and password, you can enter a description, email and disk quotas for each user. You can enable the blocking of a user account after a specified date and prohibit the user to change his password. You can also allow or disallow each user to use specific services such as FTP, web-based file manager, audio station, download station, video surveillance. There is nothing special about user groups: you can edit them and enter their descriptions.
Access rights to public folders are specified in an ordinary way: no access, read only, read & write for groups and specific users. You can also enable the following FTP/HTTP access options for each folder: prohibit to view the files, prohibit to change the files, prohibit to download the files. There is a special list of rights for an autonomous FTP user.
For NFS you can create any number of entries with names of clients that are allowed access. You can specify the type of access (read only or reading & writing) and set the root squash parameter.
The NAS has one Gigabit Ethernet controller. It has a couple of indicators and supports Jumbo Frames up to 9000 bytes.