TERRAMASTER D4-320 External Hard Drive Enclosure - 4bay USB 3.2 Gen2 10Gbps Type-C USB Storage Hot Swappable Plug and Play (Diskless)

Wow, what an incredible alternative to expensive NAS setups. This thing is incredible. Speeds are great and it’s awesome that you can swap out drives in seconds with no hardware. It’s super easy, works great, and the indicator lights on the front are helpful. Stays pretty cool as well. I could see this being very useful for people who need a lot of storage, especially video editors. Honestly might hook it up to my router for cloud storage if I feel like a NAS is necessary without having to buy something more expensive. Save your money, buy this and spend it on hard drives.

Exactly what I needed... yes, it's shaped like a NAS.... but it's 1/2 the price while having the same design, I assume. This was replacing an external drive dock that I had which didn't reduce the noise of the two white label disks I had in them. This one doesn't make it fully soundproof but it is noticeably quieter... to the point where it doesn't make a loud annoying beep... but just turns on. No USB-3 B connector... a USB-C cable.... Performance is very good and while it's not 100% quiet, it's far better than the cheap unknown brand I had before. It fits and looks nice on a shelf.... and by default, the unit comes in Single configuration which has each disk as an independent disk... no RAID or JBOD (one logical disk with two disks....) In "single" mode, it worked how I wanted it with two separate mounts to where I could easily swap out 3.5" disks as needed (which I hopefully won't need)... but nice to have the option. So it's basically like a NAS that I would have bought but it's hooked into my Mac Mini M4 which is a far better NAS interface for what I want to do with it.

UPDATE (Still be aware of your drives' power draw): Terramaster sent me an upgraded power supply (90w vs 72w) to see if it would power up the EXOS drives more reliably. The larger power supply does handle the peak power draw on these drives better. My Kill-A-Watt measures peak power draw when all 4 drives are spinning up at just under 150w, which is too much for the included 72w power supply. Most drives are not going to need this much power, and the unit will work fine for most consumer drives, and most smaller capacity drives. Check the peak power draw in your drives' user manual. This is typically not the same as the numbers on the spec sheets, at least for EXOS drives. For example, the EXOS drives peak at around 35 watts during spin-up, while the spec sheets only discuss the running power at around 10 watts. If you have issues with your drives failing to spin up, contact Terramaster and request the 90w unit, or even better, contact them before you purchase and see if they can send you one to begin with. Other than this issue, the unit is great. It is quiet, easy to install the drives, and seems to just work. That, and the fact that TM volunteered (I didn't ask) to send out a larger power supply, is why I'm bumping this to 4 stars instead of 3. I have a feeling that this unit will just work for most people. INITIAL REVIEW: BEWARE: The unit does not have enough power to spin up 4 drives simultaneously, at least with the Seagate Exos drives I put in. You may need to pull a drive, let it spin up the 3 remaining drives, then insert the last drive hot. This is the only way I've been able to get it to work with 4 drives. Apparently some manufacturers spin up the drives in sequence, rather than simultaneously in order to avoid this problem. This is a HUGE problem for a device that advertises support for 4 drives. Requiring physical interaction like pulling a drive at every power up is problematic. I haven't yet tested whether this will affect the usage post power-up. If, for example, the drives spin down, will it even be able to spin them back up when data is being accessed? I've emailed customer support about this, and will update the review when / if I hear back.

This is a really great drive enclosure for three reasons: design, reliability, and value. I really appreciated the tool-less design. I fully loaded the enclosure with 4 drives in probably less time then it would take to screw mounting plates onto a single drive for other enclosures or a PC case. This also means that drive replacements in the future will also be quick. Not as important, but the general appearance is also very nice--a very clean design. I have owned several external USB drive enclosures in single and dual bay capacities in the past, but most of them were not reliable. In the middle of long transfers, the USB connection would always drop and I would give up entirely. This led me to think that USB was too unreliable for large data transfers and external hard drives in general. I am currently using this drive enclosure for storing large data backups, merged with DrivePool with parity by snapraid. The size of an individual backup can exceed 3 TB and this enclosure has not failed me yet. The connection is reliable. Multiple drive bay enclosures can get quite expensive. That this one goes for less than the price of a large capacity NAS hard drive makes it very affordable and a good value. Would definitely buy again and would consider other drive enclosures from Terramaster in the future.

The TERRAMASTER D2-320 is an excellent value. The slide in disk trays are easy to use, and dampen noise from the disks. I'm using mine in RAID0 (striped) mode for speed. I installed a couple of my oldest NAS drives, 1 TB Samsung, into the enclosure and plugged it into my desktop Windows 11 machine. Using it as fast scratch disk while re-organizing my photographs. It works great. It'd be nice if the disk trays could be locked in, but that is not a deal breaker. I'm happy with how quiet and fast the enclosure is.

First of all, the reviews are conflating many different devices. The devices reviewed have notably different firmware and are designed and built differently. So the overall review is not really relevant. You'll have to wade though all reviews to find the ones applicable to the product you're considering. I'm just updating my review. I have been fighting for a few months to get it to work right. Thing is, no mater what, if you happen to transfer big files, or try simultaneous transfers, it will just fail to work properly and the USB control will be reset. The reset takes some time, so forget about any kind of throughput. The kernel messages seem to indicate errors in the processing of NCQ. Trying to disable it or limiting the queue depth is not allowed. I guess the firmware doesn't implement correctly those features. Another update. I have been writing firmware for devices for years. I would be embarrassed and ashamed to unleash a product that poorly done. It is missing key features that would make the product easy and reliable to use. For example, you don't seem to be able to get each disk unique identifier, the WNN. I could go further, but at that point you figured that the device is only half baked. Sure, it will work with a basic workflow and LOTS of hand holding. The heat is not extravagant, but substantial. Al in all a device where they cut so many corners to lower the price, that it is missing its usage target. I would NOT recommend it as a D.A.S.. Or anything else for that matter.

I purchased the D2-320 2-bay RAID enclosure with USB 3.2 Gen 2 10 Gbps My purpose with this unit was to mirror (RAID1) two 6TB WD Reds with a Linux machine. I’m not familiar with this brand, so I decided to test it a little before copying a lot of my files over to the D2-320. Getting everything working was pretty easy. I pulled out each bay, installing the drive was pretty easy, no screws needed. They provide a video on it if you’re unsure. I set the selector on the back of the unit to RAID1, shoved in both drives, connected the USB (drives are powered but won’t spin up until the USB is connected), then held the RESET button with the provided pin until the disk lights flashed. The system found one drive - as it should have. I wrote approximately 18K files and directories of various sizes to the array and then without disconnecting the USB or turning off the power, I pulled out one drive. I then connect the pulled drive directly to another computer to see that the files were in fact written to the drive. They were. All good to go. I replaced the drive. Both lights are green. Since no changes had been made to either drive, this is perfect, it didn’t try to rebuilt the array Next, I pulled the second drive out hot. Then connected that drive to the other computer and checked to make sure all files were also written to this drive as well. They were! It is working as it should be. I then created a couple files on the other drive and then replaced the pulled drive back into the D2-320. One drive light was blinking green, the other blinking yellow. According to the online documentation, this means it is rebuilding the RAID1 mirror. Perfect .. Everything is performing as expected. It did take a few hours to rebuild .. but these are 6TB drives, so that was expected. The USB cable provided seems adequate, USB C on both ends. If you need a different cable, consider that when purchasing. Average 1G file write 156 MB/s, average 1G read 221MB/s. Slow but these are mechanical drives connected via USB. Acceptable. Later, I watched a video using Jellyfin and reading, transcoding, and streaming worked perfectly fine. The large fan is quiet and seems to keep the drives cool. Airflow looks to be sufficient. How noisy the unit will be will depend on your drives. Some are louder than others. These drives will be part of a system I have in place which will be up and running 24/7. I’ll be very interested in seeing how well the Terramaster D2-320 performs in the long run. I’ll post updates after I have used them for some time.

Works well and stays connected but it’s much noisier than the add leads you too believe.