The ioSafe Duo is available as an empty box or pre-loaded with two hard disk drives of 4TB or 8TB each. The unit supports drives of up to 12TB, has a USB-A port and one USB-C port at the front and connects to your computer through a USB-C type USB 3.2 Gen 2 port on the back. In theory, the unit can deliver 10 Gbps throughput.
So far for the specs, now let’s see what’s inside. Inside my 8TB test unit were two Seagate IronWolf disks. Those are Seagate’s NAS disks. NAS disks are specifically tuned for many start-stop cycles and continuous use. The IronWolfs that are in my 8TB ioSafe Duo are 5900rpm drives. Those are not the fastest of the pack but the most silent and probably the ones that will last the longest as well.
The unit is made of pitch black matte metal with a laser-etched flame on one side and the red-white-blue ioSafe logo on the front door. It weighs a back-breaking 15kg. Those 15kg are entirely attributable to the fireproof and waterproof materials that are also responsible for the size of the beast — it’s about 1.5 times the size of a CalDigit T4. Behind the fireproof front door which weighs a tonne by itself, is another — waterproof — door. A nice side-effect of these massive physical protection layers is that this RAID box is absolutely silent. You can’t hear the disks spinning nor the fan running. There’s simply too much mass for the noise to reverberate into audible levels.
The Duo is designed to resist a temperature of up to 840 degrees Celsius for 30 minutes and ingress from waterjets and submersion in 3 metres of water for 72 hours (three days). All of the ports and even the RAID jumpers and fan at the back are exposed like on ordinary equipment, yet they all resist fire and water without the need for further protection like silicon gaskets, etc. That’s all due to DataCast and HydroSafe (waterproof) technology, both of which ioSafe successfully patented in May 2007.
You would be forgiven to think that all this proprietary protection means you can’t exchange the internals like disks and the ventilator, but that’s not the case. The Duo’s fan, for example, can be replaced with the use of a screwdriver only and it doesn’t even require you to open the box.
Furthermore, if you want to replace disks — or simply start with the empty Duo — that’s possible too. Inside the shipping box you’ll even find a specially designed hex tool that flexes to prevent you from under/over-tightening the screws or damaging the waterproof gasket. However, that isn’t an invitation for regularly “rotating” the disks inside as the waterproof materials do wear if you often disassemble them.
In fact, the only weak point in the Duo are the disks themselves. That’s why ioSafe advises to keep them set at the default RAID 1 configuration, which offers disk failure protection. Of course, if you want the most stringent protection in that department, you’ll need a RAID 5 box (and even then you’re not 100% protected as even the briefest of power glitches while the RAID is rebuilding will render the checksum, on which RAID 5 depends to rebuild the data after disk failure, useless).
The Duo is your best bet for a safe local backup and, in my opinion, much more secure than cloud backups where you have to take into account a number of issues like exposure to hacking. It’s relatively fast as well, although the Duo isn’t a speed demon. The fastest throughput I was able to squeeze out of the 5900rpm disks was 220MB/sec. If you fill it up with two SSDs you should be able to reach speeds of around 400MB/sec, even in RAID 1 configuration.
The Duo can be had for $399 if you buy the empty box. For my 8TB test unit you’ll pay $649. A 16TB version retails at $899. The Duo comes with two years of free data recovery service included. A list of qualified drives for the Duo can be found here.