Are LimeTech builds called NAS? (6TB WD60EFRX has restrictions here)


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The 6TB WD60EFRX Reds have a restriction. They are certified for max. 8 drives in a NAS system.


Now I'm wondering if I can put more than 8 drives of that type in my 15-drive MD-1500/LL and MD-1510/LL original LimeTech builds. So, do the LimeTech builds act like a NAS - whatever that means?


Thanks in advance.

I see on this pdf which seems to say something similar.  They don't say "certified for max 8 drives" they say "designed specifically for."


Frankly "limiting" any drive to a max number in a machine is ludicrous.  I see no reason why you could not have 24 of those drives in a system.


If there is something in there that limits it to 8 drives I will no longer be selling them and will start complaining loudly to WD.

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First, how will they know what it is in when you RMA it?


Second, partly related to their ability in #1, is that I'm going to bet this is geared towards storage enterprises who they'd rather buy their enterprise drives.  It will mess with the economics of the likes of Backblaze.  They try to RMA a drive WD will know.



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Thanks for your answer.


During the last two days I was searching the web for this. Seems that the Pro series tolerates synchron vibration of up to 9-16 drives and the non-Pro series of these drives fails on this.


On the other hand unRAID has sychron vibrations during parity-check and  disk-rebuild only. The unRAiD towers look more stable than typical NAS systems and their drive-cages. And what does that 3D-balanced firmware do when it fails on 9-16 drives. There are a couple of bad reviews on Amazon of people who used that drive in >8 drive NAS.


So I'm wondering if it's save to add 15 of the non-Pro drives to my LimeTech towers...


Two are already in here and they perform quit fast even on my old SATA controllers from 2008/2009.



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First, how will they know what it is in when you RMA it?


On Amazon several people report two or more drives failing at once during data-rebuild - something that produces high vibrations. So data is lost even when you are able to RMA.


So, you would use 15 of that beasts?


Do they also report running preclear or putting the drives through the paces before using them? Those drives could have been mostly dead on arrival. So I wouldn't take much stock in 2 drives failing at once on data rebuild if they didn't properly test them before hand. Very novice mistakes.

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Of course I would.  What do you think people did before Red NAS drives?  They use Green, and not Green, drives in high density systems.  Backblaze uses like 40 of them in a single box (Red and non-Reds).  Have you heard about massive failures from these drives in high density systems?  Do those drives make any claims at all about "vibration tolerance" for a certain number of drives?


If vibration is REALLY a concern then it is best dealt with physically with dampening at the case level.


Those Amazon reviews ahve no idea at all what caused the failures.  They are both anecdotal AND completely non-evidence based.  Did they measure the vibrations?  Compare to other systems with other drives, in the same case with the same work load, but fewer drives?  Did they do this over multiple iterations to establish it isn't random?  Infant death syndrome? Because they bought the drives from the same manufacturing batch (same vendor same time) a possibly suffering from the same marginal production tolerance?

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My take is that this is purely a marketing ploy.  Like daily replacement contact lenses which are actually engineered superior to monthly wear.  They start with the premise that average Joe can afford $20-$30 a month, so you can buy one pair of monthly lenses or 30 pairs of daily lenses for about the same.  I have been wearing daily wear lenses changing them on a monthly cycle for 20 years.  My optician hates me.


I suspect this Red vs. Red Pro is exactly the same.  Enterprises have deeper pockets, WD can charge more for Pro (and they will), there won't be very many home NAS users with more than 8 bay systems and the Red 6TB's don't contribute enough profit if sold to Enterprises.


I am in the process of filling one of my 20 bay towers with Red 6TB drives, first impressions is they are a great drive.


On a secondary note, mount half your drive cages upside down to cancel out vibrations on synchronised activity (eg parity check/build).

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Nope your English is just fine.  There is no actual explanation for a 5-drive limit other than wanting to push customers to the enterprise drives. I don't blame them, but I also don't have to fall for it.


The daily data limit has nothing to do with drive density, it has to do with usage pattern.  Note the lack of any explanation of what is actually different between the enterprise vs. RED drives to justify the daily data rating. I'm just going to guess that it is more about amortizing the supposed likelihood of higher warranty claims on heavily utilized drives.  Backblaze data says that doesn't hold water.

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  • 2 weeks later...

I believe that the drive limit has more to do with the NAS systems that use a more traditional RAID that is striped across all disks.  The reason these NAS drives came about is the increase in NAS devices that RAID.  The typical consumer desktop drive do not function well in a RAID environment causing drives to drop out of the array, this has happened to me on more than one occasion.  Most consumers are not willing to shell out the money for enterprise drives for more than twice the green drives cost.  So the drive manufacturers developed a drive that has is a mixture for the green drives and enterprise drives creating the NAS drives.  These drives are basically green drives with firmware and hardware improvements suitable for home RAID environments.  They also don't have all the functionality of enterprise drives and this is why they are much cheaper and have the limit.


Since unRAID isn't a RAID and each disk is independent you could put as many as you want in you server or PC as long as they are not in a traditional RAID or other RAID that data is spread across all disks.

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There is no issue using as many of these drives as you want in an UnRAID setup.


As you've already noted, it's VERY unlikely you'd have active seeks on anywhere close to the rated 8 drives at a time anyway.  (Most will typically be spun down).


In addition, r.e. your comment:

On the other hand unRAID has sychron vibrations during parity-check and  disk-rebuild only.

... NOT true.  During parity checks or disk rebuilds, the disks are all accessing the same cylinders at the same time, so there's VERY little seek-induced vibration (unlike a NAS that's serving multiple clients with multiple simultaneous accesses on different disks).    This is a FAR less stressful environment than a traditional server.




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I did preclear these drives and they did not show anything bad. They show less SMART keys than the ST3000DM001 for example, but what they show looks perfect.


WD reports fewer parameters than Seagate does; and Seagate also shows some raw data that often causes unnecessary concern in looking at the results (e.g. high-fly writes).    If your drives pre-cleared okay, then they're fine to use in your array -- and as I noted above there's no problem using 15 of them if you want  :)

[That will be a very nice setup with 15 of these babies -- 84TB of fault-tolerant storage !!]



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