Of course, network connections that support Gigabit Ethernet are Priority No. 1, but the ability to connect to multiple external storage devices is a close second. USB 2.0 support is taken for granted, and I couldnt imagine a device lacking it; the focus is shifting to USB 3.0, which will become useful in the months to come. Interfaces such as eSATA are nice to have as well, but for reasons we cant quite fathom, that ones never caught on for portable storage. FireWire connectivity, which used to be essential, is becoming less so thanks to the ubiquity of USB 2.0. I also want devices to be available as an iSCSI target to allow their use in clustered or virtualized environments.
RAID support to levels 5 and 6 is far preferable to a JBOD installation. RAID 6 is much less well known than RAID 5, which preserves data integrity in the event of a failure of one physical drive in the array; it provides twice the protection, by preserving data even if two physical drives go bad. Just a bunch of disks might maximize the devices capacity but provides no protection against drive failure.
Even if only one person is going to be using the device in the ordinary course of business, its still a good idea to implement encryption features if theres any sensitive material that might be stored on the device. For multiple-user scenarios, security becomes exponentially more important; is there any way that a rogue user, especially one with trusted credentials, can get at data that he or she has no need to access?
Noisy fans and drives make even the most attractive desktop storage unit an obnoxious companion. Can the thresholds for fan speed be adjusted through the management interface? Can the devices power consumption be reduced through Wake-on-LAN or scheduling drive spin-up and spin-down? How easy is it to add support for a UPS (uninterruptible power supply)?
9Warranty and Support
If a drive needs to be replaced, how easy is it to get parts? Does the manufacturer offer next business-day replacement service? Can user-supplied drives be used when official replacement parts are no longer available?