The NASes we are discussing today are designed for two and four HDDs. The new firmware version adds a few new options concerning disk arrays and a different interface for managing them. Besides standard RAID types, you can use the Synology Hybrid RAID (SHR) feature which automatically selects the array type to use and changes it whenever you add more disks. The developer claims this mechanism makes it all simpler and easier for inexperienced users to work with fault-tolerant disk arrays. As before, you can manage your arrays manually if you select the ordinary mode. Migration without data loss is supported (from one disk into RAID1 or RAID5, from RAID1 to RAID5, and from RAID5 to RAID6). You can add a replacement disk or expand your disk volumes. SMART technology is supported: you can check out the attributes and run the integrated tests.
For some usage scenarios, perhaps not very frequent at home, the support for iSCSI volumes may come in handy. You may want to use it with virtual machines, special-purpose applications and operating systems.
Data stored on the NAS can be accessed via all the popular protocols: SMB/CIFS, NFS, AFP, FTP and HTTP. Domain integration and the operation as a local master browser are supported for SMB/CIFS. There is a network recycle bin for deleted files, which is a good thing for users who are accustomed to it. NFS has no settings. AFP is for Apple computers and allows using the NAS as a backup storage device for the TimeMachine utility integrated into Mac OS. Synology’s FTP server is among the best as its settings allow providing secure access to files from any Internet-connected device. You can specify port settings, enable encryption and UTF encoding support, and limit the speed of client connections. Anonymous connections and a write-only mode for shared folders are supported.
User rights management is based on name and password. You can unite users into groups and assign rights to those groups rather than to individual users. Besides the typical rights like no access, read only, read-and-write assigned to specific shader folders, you can assign disk quotas or limit access to specific applications, e.g. to the FTP server or download station.
Shared folders can be individually encrypted in DSM 2.3 with the AES algorithm. The encryption key can be changed or the encryption can be removed altogether when necessary. In the most secure mode the key must be entered after each reboot of the NAS. Without the key, the encrypted data won’t be accessible.
The NAS connects to a LAN via a Gigabit Ethernet port. It can use Jumbo Frames up to 9000 bytes and DHCP for acquiring its IP address automatically. The NAS has integrated PPPoE and DDNS clients as well. A firewall has recently been added into the firmware to ensure additional protection. For more security, there is a mechanism that blocks access if an attempt to guess the password is identified. One of the most interesting innovations in DSM 2.3 is the support for wireless connections via Wi-Fi adapters with USB interface. There are already a dozen of devices on the compatibility list.
One more network feature is the automatic configuration of routers for the NAS to access the Internet. Unfortunately, it only works with about 30 different models and we had none of them at hand to check this feature out.