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Question: So I bought one and put two Seagate NAS 4 TB drives in.  These drives are shown in the Buffalo config software as having only 3.7 TB.  Why is that?
Document: I have owned two Buffalo LinkStation NAS units. I hated the first one (primarily due to crappy, confusing software), and really liked the second one--the new Buffalo LinkStation 420 2 TB 2-Drive (2 x 1 TB) High Performance NAS. This device was super easy to install (primarily due to pretty good software this time around), and performs extremely well--particularly under heavy loads.
That was 4 days ago.With 500GB to be transferred from the Ready NAS and about a terabyte to be transferred from the Seagate Central both of which are Ethernet wired, I am seeing transfer speeds of less than 1MB/s, far under performance I have experienced with either of the two source devices for backups or copying.This review is a work in process, one I will update as I have more opportunity to manipulate this unit but right now just getting the data available on it is a disappointing chore.
That is just criminal.3)  The LEDs are dim - really dim.4)  The software that shipped with the hardware was rev 1.01 - the current rev is 1.31. You should download the new version before doing the installation, so you don't have to do it a second time.5)  My old Buffalo NAS could be powered up and down via the NAS Navigator software that comes with the station. That way it was off when all the computers were off.
I found the Buffalo LinkStation 420 was a snap to set up. Just plugged it into my network, ran the included software CD, and I connected to it right off without any issues. My Windows 7 computer recognized and saw the LinkStation 420 on my home network, and I was able to access the share folders without any trouble.One of the first things I did was upgrade the unit's firmware via the included &#34;NAS Navigator 2&#34; software.
Since most people will be running the Linkstation 24/7, I wouldn't worry too much about this. The supplied Ethernet cable is the flat ribbon kind with no markings, so the type cannot be identified (Cat 5?, 5e?, 6? )Inside the Linkstation 420 I found two Toshiba DT01ACA100 desktop grade hard drives (see pictures). Toshiba is new to the 3.5 inch hard drive market.
Answer from Buffalo support is self explaining:&#34;Thank you for contacting the Buffalo Helpdesk.Buffalo external USB drive are recommended. Others USB drives are not supported may be they work may be notIf you have any additional issues or feedback please do not hesitate to contact us againRegards&#34;I tried all brands of USB drives I had at home. NONE has worked WD, Samsung, Seagate.... on both USB 3.0 and USB 2.0 ports...
Bought this product because 1TB drive with Pictures, Movies, Music died on me and although I had pictures backed up lost a lot of media and documents that I was not able to get back. Allows for many different configuration. I have mine setup so that each 2 TB drive mirrors itself so if one hard drive fails I can take it out and replace it without loosing data. Also works great with streaming content on hard drive over network to smart TV.
The Buffalo LinkStation 420 is a simple-looking two-drive NAS with two 1TB Toshiba (in my copy) drives installed, configured as a RAID0 array. RAID0 gives you the benefit of combining the capacity of the drives and improving performance by splitting access across the drives, but it has the big disadvantage of no redundancy. With a RAID0 array, if one drive fails, you lose everything on both drives.The 420 allows you to reconfigure as RAID1, otherwise known as drive mirroring.
The device is fairly quiet, and it doesn't run hot. Also,this unit offers two USB ports (one USB 2 and one USB 3) for extendedUSB device serve,r and I think that's a plus. To me and my usage(streaming media to my phone, tablet, etc) this is solid and reliableserver solution. The apps from Buffalo that can control and accessthis unit are not the most user friendliest apps, but for now they areusable.
I was looking for a NAS that would fit on my shelf and connect to my 1 GB Switch. Well it took a while for it to mirror the 3 GB drives as RAID 1 (almost two days) but the system is quick and easy to use. I am told by Buffalo's Tech support that it will support Dynamic DNS but have not had time to pursue this capability. I am using it for file storage and as a media server and will eventually use it for remote FTP capabilities.
Answer: 3.7 TV is the normal available  space for 4 TB drives,  some space is used as the index of files on the drives and the drives are listed as 1000 gig  x 4  but the software the system itself calculates 1024 gig as a TB,  so shows a smaller value.