After about a week of running flawlessly, I was notified that there was an available software update, and that I needed to reboot the NAS. I allowed it to reboot, but then noticed that it didn't come back up on the network. It turns out that, the MAC addresses on all three of the interfaces (10G, 2.5G, and 1G) had changed to seemingly random values (this caused my DHCP server to give them different IP addresses).I thought this was weird, but I attempted to connect through the web interface to the new IP addresses, and was given the initial setup screen (i.e. it was behaving as if it were a completely new unit). Following the advice of QNAP customer support, I reset the device to factory settings, and went through the setup process (being careful to not re-initialize my drives). This did not work; the setup process' progress bar went to 99% and then stayed there (I waited on one attempt for over 20 hours).In this state, every single time the device rebooted, there was an entirely new set of MAC addresses, and the device claimed that it couldn't see any of the installed drives. QNAP customer service was completely useless; they kept telling me to SSH in to the device to run some commands after I repeatedly told them that the device wasn't even listening for SSH connections. Each time I would try to SSH in, and report back that it wasn't working, they would fall silent for a day or two, and then come back acting as if this was the start ofd a new support ticket, and we'd go around the same circle again.Eventually, they offered to remote into my PC via Team Viewer. After agreeing, and giving them the required info, they again went silent, and never connected; I waited until nearly an hour after the appointed time.Eventually, they told me there was nothing they could do and I would have to reinitialize the disks (thereby removing any hope of recovering my data), and I did so.After which, the device was still in the same bad state.Assuming I just got bad hardware (it happens), I exchanged it for a new one at Amazon, and after setting it up, and copying a few hundred GB of test data to it, I rebooted it. And this second device is now in the same state as the first one had been in (i.e. doesn't think it has any drives installed, new MAC address on every boot, and thinks it's a new device that hasn't yet been set up).One bad device can be understood, but two in a row is just shoddy QC. I can't see anyone ever convincing me to buy a QNAP device again.Bad hardwareBad softwareBad support

I've used a QNAP before, in a work-related setting, so I already knew what to expect. These are reliable devices in my experience, and they get the job done, especially the core job of a NAS: acting as a backup drive and file repository/server.One thing to expect is to read a lot of online material, probably mostly through forums, where you're likely find clearer and quicker answers than in the formal documentation.The device is high-quality, and mostly pretty easy to set up. However, you have to jump through a lot of fiddly hoops to enable CIFS/SMB (Windows file sharing) and NFS (Unix/Linux/macOS file sharing( on it, and actually use it as a backup device. This stuff should be much, much easier to find and configure, and a wizard should walk you through it right at first-setup time, since 99% of people buying this want to use it as a backup drive through one or both of those protocols.I find it very frustrating that QNAP goes out of their way to try to prevent you installing any Unix/Linux software that they did not pre-approve (their QTS is a form of Linux). Sure, it's for the same general reasons that Apple and Google try to lock down iOS and Android, but it's still really, really annoying for tech-savvy people (though there are ways around it, which you'll have to do some online research about, if you need it). The already "approved" and available apps are frankly too few. They need to open this up more to open-source development teams, instead of mostly just partnering with commercial software providers who ultimately want to sell you something. E.g., it's really weird to me that this has no available CMS to install other than Joomla, and no blogging platform other than WordPress, nor any wiki alternative to MediaWikia (which is bear to administer). All that said, operating as a server of sorts is just add-on functionality for what is primarily a backup storage device, and QNAP is among the top three or so providers in the NAS market. I can't personally gauge a sharp distinction between them, other than this beats the pants off some of the not-in-the-top-3 providers.The tools for managing devices and logical volumes are pretty good. It's potentially convenient but potentially also massive security hole that you can use this as a cloud server, either directly or through an interface at QNAP's own website. I like the concept, but I believe it turns on too many things by default, and is too unclear about what they mean and what their potential for abuse is, when you first enable this stuff. Honestly, it is best to set up and test all features of this device over several days and decide what you want to do with it, BEFORE you start using it as your backup storage. And definitely create a proper user account with a unique password to act as the active administrator, instead of using the default admin account (and scramble the password of that one with some very long gibberish - but be sure your personal user account actually is set up as an admin first!), since people trying to system-crack your device are going to be going after the built-in admin account).Another dumb thing is that pretty much everything you install as software for QTS ends up running at all times, at least in "stub" loader daemon form. It's a lot like installing phone apps, and it wastes a lot of RAM and CPU power. So, don't install every QTS app that seems like it might be useful some day. Only what you plan to use right now. If you turn out not to use something, uninstall it. Another annoying symptom of this problem is that when you need to restart the QNAP, it takes FOREVER to shut down all these apps, and will sometimes just outright fail at it, requiring you to do a forced shutdown. This is weird and senseless. No computer of any kind, be it a Windows PC, a Linux workstation, and Mac laptop, a game console, a router/gateway, a phone, or anything else of this sort, takes even a fraction of the time it takes a QNAP to shutdown and/or restart. I'm going to call this an outright bug; something about its process management is simply screwed up. But this is not a fatal problem, simply an obnoxious one.Anyway, I have this device running 24/7 and it does not exhibit any operational/reliability problems. It's not the quietest thing in the world, but I also have a HEPA air filter and a PC running all the time, so the QNAP's sound just fades into the white noise. If you prefer total silence you may want it in a closet. Or if you're DIY-oriented, get a Noctua (quietest brand ever) replacement fan for it. Just keep the original in case you have to RMA the QNAP within its warranty period. Given the price, I think buying the extended warranty is a good idea, but only just before the original warranty expires.