NAS / OpenMediaVault

[pfeerick]

Note: If you came across this thread because you wanted to find the great OpenMediaVault images for the rock64 that ayufan has slaved over, jump over to https://github.com/ayufan-rock64/linux-b...ses/latest and look for the jessie-openmediavault-rock64 images. But please do come back and read this topic at some point soon, to ensure you get the best possible performance from your setup! 

Due to the rather attractive feature set of the rock64 for it's price point (USB3 port, dedicated USB2 ports, Gigabit Ethernet, up to 4GB of RAM, up to 1.5Ghz quad core 64bit processor ), one of the expected uses for it is as a Network Attached Storage device, either running your own custom setup, or perhaps OpenMediaVault (I'd recommend the latter... you can't beat a pre-configured web-gui driven setup that's ready to go out of the box!  ). And talking of performance, I can't resist not posting this excerpt from tkaiser as to just how good the rock64 can be when configured right:

We're talking about +380MB/s on average with UAS. This is close to the maximum what we can get with USB3 SuperSpeed anyway (400MB/s or to quote the specs: "At a 5 Gbps signaling rate with 8b/10b encoding, the raw throughput is 500 MBps. When link flow control, packet framing, and protocol overhead are considered, it is realistic for 400 MBps or more to be delivered to an application.")

But this doesn't mean the road won't be rocky... there are things that can go wrong... from unstable power supplies... to configurations that just won't work... to glitches in the software that result in unpleasant surprises. This post attempts to pull together all of the various bits of information about potential problems you might encounter, and also to link to some of the more interesting bits of info about using the Rock64 as a NAS/OMV device. 

Before you read the performance related stuff, it may be wise to read this thread about what does all this benchmark stuff really mean!

Performance data:

• Some OMV GbE transfer statistics
  
• USB3 Storage device benchmarks - OpenMediaVault, USB3 performance thread 
  

Other useful stuff:

• If you're thinking about NAS / OMV, you're probably thinking about external storage. The best chipsets to use are JMS567, JMS578 or ASM1153E (the latter is only an issue in Seagate disk enclosures due to branded/broken firmware). And the pine64 store stocks a pretty cheap JMS578 USB3 to SATA cable (which is suitable for 3.5" disks with additional 12V/2A PSU, and *possibly* 2.5" drives without a powered USB hub, although one would be strongly recommended). If you want other optoins, similar items under the YEYI and ORICO brands, with the latter also having a full 3.5" disk enclosure relying on the JMS578 chipset. They can be found for as little as US$4.99 on AliExpress at the time of writing, and you might even be able to get them cheaper with the odd coupon that goes around...
  
• A lot of other people have used the Odroid XU4 as their NAS/OMV device. And when you consider the specs, it's no wonder why. However, specs are not everything in a NAS/OMV devices, real-world performance is. Configured correctly, and with the right hardware, the rock64 can probably outperform the Odroid XU4, whilst running cooler and consuming less energy. However, please make up your own mind on this... have a look at the threads on the Armbian Forum and the OMV Forum where tkaiser has collected a lot of benchmaking data, and stimulated discussion about real-world performance and usability. 
  
  

Potential Issues:

• USB RAID: In a home use application, it is a plain joke, as it isn't true RAID to start with. Plus, you can get into funky situations where your RAID setup actually shuts itself down due to undervoltage, making it lose and corrupt things all by itself. Someone on the IRC chat put it like "USB RAID (with one USB hub in between -- let some disks do some work --> under-voltage --> hub disappears from bus --> all disks are gone at the same time --> RAID my *aunt*).
  
• Undervoltage: This is very common issue in the SBC world, and is because mobile phone / USB chargers are simply not suited for powering SBCs. Save your self some unnecessary pain and suffering, and get the proper rock64 power supply. Its good, cheap, and will prevent random file system corruption, crashes and your rock64 suddenly powering off due to a undervoltage issue. And if you want to use external hard disk drives... you really should use a powered USB hub, as the rock64 will probably be able to power them if used with the correct power supply, but you are simply asking for undervoltage issues or for your external HDD to not power on properly. 
  
• MicroSD fakes or poor performance: This issue crops up again, and again, and again. Regardless of if you buy a 'name brand' microSD from your electrical supply store, supermarket, or from a reputable online seller, fakes can be introduced anywhere in the supply chain without their knowledge, and regardless of that, the microSD could be faulty on arrival, or just not a suitable one for SBC applications. My personal recommendation is that you should get yourself a Samsung EVO(+) MicroSD. They have been tested numerous times, and provide excellent performance at a good price. And after you get one, still use something like h2testw (on windows), or F3 for linux and Mac, to check that your microSD is really the size it claims it is, and doesn't have any faults right from day 1.
  
• Error messages not quite meaning what you think: For example these logs might make you think that the uas_eh_abort_handler errors are an indication there is is something wrong with the UAS drivers or support on your system. However, in this particular case, the issue was actually an underpower issue for the cradle, and was occurring during some random write tests, as as that is when a disk drive is the most power demanding.
  

More will be added to this post as time goes on. Please feel free to make suggestions for more links and information to be added.