I have a lot of hard drives and I’m always buying more. I have three 8-bay Synology NAS and I always seem to want more free space. Since Synology allows mixing drive capacities, I have been continually buying higher capacity hard drives and replacing smaller capacity drives. I was boxing up the phased out drives and stuffing them in a closet because these are good quality drives and all showed 100% health. I was not going to get rid of them, I did not need to use them in any of my computers, and I did not want to deal with the hassle of selling them. Before knew it, I had fourteen WD Red NAS drives in the closet.

I decided to buy a cheap 16-bay Norco 3U rack mount enclosure and take parts from an old computer. These parts included an Intel i7-3770, 32GB of RAM, and an 850 watt power supply, so this file server was going to have decent power. I had to purchased a couple LSI RAID cards (in IT mode), some cables, and a few other accessories. I wish I had purchased a SuperMicro chassis and saved myself some money, but that’s another story.

I had Windows 10 on the computer I used for this file server so I experimented with Microsoft Storage Spaces. I was underwhelmed with using Windows so I tried Xpenology. In short, Xpenology uses the Synology NAS operating system on non-Synology hardware. After a lot of trial and error, it worked but had minor irritations from time to time. I was also worried I may not be able to update my system because Synology is working to prevent something like Xpenology. This would not be the end of the world because I will eventually use this system for local backup and not have it exposed to the internet, but I still prefer systems I can keep updated against threats.

I considered TrueNAS (formerly FreeNAS), but I believe you cannot use RAID with different capacity drives. I considered using TrueNAS and just making RAID groups with drives of the same capacity, but realized this would be troublesome for me. This was because I would be phasing out the smallest drives with larger drives as they become available from my other systems.

I was already aware unRAID supported supported creating RAID arrays with drives of different capacities and I was constantly seeing unRAID mentioned in forums, so I decided to use the 30-day trial.

I installed unRAID by using their utility to configure it on a flash drive. I was not too pleased that unRAID must run from a flash drive and not a local hard drive or SSD. I bought a 32GB Samsung flash drive that was low profile so I could have it on the front of the case. I wanted to use a 128GB Samsung flash drive I already had, but unRAID specified 32GB as the maximum capacity. I decided to go man style with using unRAID for the first time, so I read as few instructions as possible. I discovered I needed to connect a keyboard, mouse, and monitor the first time I booted unRAID. Once I made a few tweaks I was able to connect via a web browser. I guess it’s handy that I can connect directly to unRAID in case of an error preventing me from connecting via a web browser. This is something I cannot do on a Synology NAS.

I did a quick read on how to set up RAID because this can take many hours and I did not want to do this more than once before I could get to using the system. I went with the XFS file system with two parity drives. These are old drives with thousands of hours of run time, so two parity drives was the minimum for me. I had no experience with the XFS file system, so I was eager to try it out. The RAID array took a while to configure, but it was done a lot faster than I expected (I think around twelve hours). The RAID build process even survived me accidentally stopping the array for just a moment. I’m not used to an option to stop and array and of course I had to accidentally click on the bottom.

Once RAID was configured, I saw that one 3TB hard drive was showing as unhealthy (a thumb down icon). Should I pull it or use it? I had extra 3TB drives sitting around. Of course I wasn’t going to replace it and I was going to start copying terabytes of data to the system. I quickly saw that the write speeds were slow at around 40MB/s. I researched this and saw it was normal if not using a cache drive. I hadn’t wanted to give up a drive bay for a cache drive, nor did I want to pull the chassis from the rack to install a drive internally, so I decided to make some tweaks via SSH. Next thing I knew I was getting around 80 to 90 MB/s.

I saw that unRAID copied to my highest capacity drives (6TB) until they were a certain level full and then went on to the next biggest drives (4TB). unRAID continued to go back and forth between my 6TB and 4TB drives instead of moving on to my five 3TB drives. It was going to be a while before data was going to be copied to the 3TB drive showing unhealthy so I decided to swap it out to see the rebuild process. I read the instructions on how to do this and the process completed in something like nine hours. I then restarted the data copying process. Before the copy process could complete, I again phased out a 6TB hard drive from another NAS so I decided to swap out a 3TB for a 6TB in unRAID. I repeated the process to rebuild RAID and it was saying it was going to take fifteen hours to complete. I can understand this rebuild process taking longer since I had copied terabytes of data since the previous RAID rebuild. I only saw around 21GB in use on the drive I replaced, but unRAID seemed to be adding data to this higher capacity drive. I would report how much data it wrote to this drive during the rebuild, but I will finish this post before it is done.

I kind of like to say unRAID is idiot proof because of a few mistakes I made. As already mentioned, I accidentally stopped the array when it was initially setting up and this was not an issue. What worried me was when we had a power outage and I did not have this system connected to one of the many battery backups I had in the rack, hence the main idiot part. I powered on the system and it booted without any issues. I didn’t even get a dirty shutdown message like I would receive from a Synology NAS.

I’m used to free Linux and Unix software, but this will be the first one I purchase (though I’ve donated plenty of times). I need the $129 Pro edition because of the number of hard drives I have, but I feel it is worth it.

Though I will be purchasing unRAID, there are a couple things I would prefer they change (or make it a simple option).

  • I would prefer being able to install the OS to a local drive because flash drive are not too reliable. unRAID will allow you to change flash drives, with some limitations.
  • I would like to be able to backup my configuration to a file. The unRAID forums say to copy the “usb/ver/date” directory or copy the entire flash drive.
  • I would like a setting to speed up certain functions since unRAID uses very little resources with the stock configuration. One example would be how I increased the write speed without a cache drive. I would like to unRAID to use more RAM, more CPU, etc. without having to use command line.

I have a lot more testing an tweaking to do before I am satisfied. I will update this post from time to time when I discover anything worth mentioning. Other than that, I really like unRAID and it will be worthwhile for me to purchase for my backup server.