Low Power Hard Drives

[Ben123]

So I'm about to take the plunge and build a FreeNAS box, but I'm really struggling to select the hard drives to use. I'm going to have a 24-bay case and I'm currently considering a variety of configurations that I welcome comments on...
4 vdevs of Z2 with 6 drvies each
3 vdevs of Z3 with 7 drives each (3 bays empty or spares)
2 vdevs of Z3 with 11 drives each (2 bays empty or spares)
...but that's not my current problem.

My current problem is I can't find a drive I like. Power utilization and compatibility with the number of drives are my concerns. I'll be the only user and it'll be in my basement so I don't like the idea of paying for more power than necessary. Given my very infrequent access (1-2 hours/day on average) I might even consider spinning the drives down.

So to my HD problems:
Seagate NAS: 1-8 bays ....so they're out
Seagate Enterprise NAS: 1-16 bays & 7200 RPM...too much power use
Seagate Enterprise Capacity: No bay limit, but 7200 RPM and ~10W !?
WD Red: 1-8 bays ....nice 5400RPM...I'd prefer these if they didn't have the 8 bay limit
WD Red Pro: 1-16 bays & 7200 RPM...too much power
WD RE: No bay limit, but 7200 RPM and too much power....also paying for reliability and performance...
WD RE+: No longer listed on their website...judging by availability they're discontinued?
WD SE: Seems to trade substantial reliability/performance for very slightly less money than the RE models.
WD AE: Scary low MTBF/Workload relative to RE...are these the rejects? 5900RPM is nice though.
HGST He: Seems like the best bet...7200 RPM, but attractive SATA model power usage (6.8W in use, 5W idle)...pricey though

Anything else I'm missing or not considering? Opinions on something like 24xWD Red? I'm a little scared they said 8 drives for a reason (vibration) and don't want to risk my data.

Thanks,
Ben

 

[Ericloewe]

1-8 bays

I'd prefer these if they didn't have the 8 bay limit

1-16 bays

That's marketing bullshit. Don't pay attention to it.

 

[Mirfster]

Anything else I'm missing or not considering? Opinions on something like 24xWD Red? I'm a little scared they said 8 drives for a reason (vibration) and don't want to risk my data.

My current problem is I can't find a drive I like. Power utilization and compatibility with the number of drives are my concerns. I'll be the only user and it'll be in my basement so I don't like the idea of paying for more power than necessary. Given my very infrequent access (1-2 hours/day on average) I might even consider spinning the drives down.

Just because you have 24 bays; it doesn't mean you need to use all of them right now. Not sure of the space requirements or actual use case; but you could start off with a single vdev of like 6-8 drives (recommend at least a RaidZ2; unless you are looking at iSCSI). Then add vdevs to the pool as desired.

Having 24 "low power" drives may be the same or more as 6-8 "normal power" drives.

 

[depasseg]

I would consider going with 2 separate pools (with one backing up the first).

What are your storage requirements (capacity and performance)?

I would go with enough drives in the main pool (likely raidz2) to get your capacity, and then make the backup pool a bit bigger. Then just use zfs replication to make a backup every couple hours and otherwise have the backup drives spin down.

 

[jgreco]

mod note: This isn't a resource. Ejected from the Resources forum.

 

[Rand]

Additionally, whats your general use case?
Depening on monetary/space/size/speed/availability constrains you could go for flash only or 2.5" drives or desktop drives with low power envelope (eg WD green's with wdidle).

 

[jgreco]

I'm a little scared they said 8 drives for a reason (vibration) and don't want to risk my data.

Vibration is an issue.

https://www.pantz.org/hardware/disks/what_makes_a_hard_drive_enterprise_class.html

But be equally aware that there are significant marketing reasons for them to segregate the classes of drives.

The Seagate Desktop ST4000DM000 is about $110.

The Seagate NAS ST4000VN000 is about $130. The difference between those two drives is probably nothing more than firmware tweaks.

The Seagate Nearline ST4000NM0024 is about $260. Double the price. The mechanism is a slightly better quality. There's vibration mitigation.

So the benefit to Seagate to sell a NAS class drive is that they can charge somewhat higher prices for it. What you, as a consumer, get is basically the TLER feature. That might be worth it.

But from my perspective, two NAS class drives will always be more reliable in aggregate than a single nearline drive, and the price comes out to be a similar thing. I'd rather buy the cheaper drives and put some money into additional redundancy. ZFS will catch errors. The risks of the missing vibration mitigation are not that high.

Also, there's nothing magic about the number 8. In a server, vibration's an issue starting with disk #1. The big vibration source in a server are the cooling and PSU fans.

 

[TXAG26]

If I recall, when these NAS marketed drives became popular, with the release of the 2/3/4TB versions, as well as the drive-branded NAS appliances, both Seagate and WDC had them listed as 1-5 bay. Then one of them, can't remember which, started marketing "their" NAS drives as 1-8 bay. Everyone else followed. I'd bet a case of beer that nothing physically changed with the drives between the "1-5 bay" and "1-8 bay" marketing campaigns. Just my $0.02 though.

FWIW, I like both the WDC Red NAS drives and the Seagate NAS drives. I'd go by price/TB between those two lines, and get whichever is the best price. If all else were equal, including dead even on price, I'd probably favor WDC Red's by just a hair since they now have 6TB & 8TB Red NAS drives out. Last I checked, the 5TB Red NAS drives were in a nice sweet spot regarding price/TB.

 

[jgreco]

You recall correctly. I had forgotten that, but obviously it says a lot.

 

[Ben123]

Thanks for all the advice and opinions. I too recall when they changed from 1-5 bay to 1-8 bay support...good point on how arbitrary that limit is. Given everything said here, I think I'm leaning towards starting with 2 vdevs of 7 WD Reds in Z3 with room for an additional vdev later. I think I'll grab the new WD Red 8TB model....early adopter premium for sure, but they seem like they're just HGST He8 SATA drives that spin at 5400 instead of 7200. Anyone know of any other differences?

 

[jgreco]

I don't think they are, but I can't cite anything. I do know that some of the WD My Books have been shipped with 7200 He8's in them, see

http://www.pcper.com/image/view/67830?return=node/65053

I've been pondering going down to Best Buy and maybe acquiring some. At $250, that's an attractive price even with no warranty.

 

[TXAG26]

I don't think they are, but I can't cite anything. I do know that some of the WD My Books have been shipped with 7200 He8's in them, see

http://www.pcper.com/image/view/67830?return=node/65053

I've been pondering going down to Best Buy and maybe acquiring some. At $250, that's an attractive price even with no warranty.

I picked up the only two 8TB My Books at my local BB had and they indeed shipped with the 7200 He8's! These two were hidden on the shelf behind the 4TB drives and there wasn't even a shelf tag for them yet. My understanding is that WD only shipped a small first batch with the HGST He8's. The ones that followed may have a WD Red 8TB w/a different firmware.

 

[jgreco]

Oh snap, now you're pissing me off.

 

[TXAG26]

Oh snap, now you're pissing me off.

I haven't de-shelled them yet, but they benchmarked identical to the PCPER article. One of my drives was actually a couple MB/s faster and one a mere 1 MB/s slower than the PCPER review. All within spec for USB 3.0. Well over 200MB/s+, which isn't obtainable with a 5400 rpm drive.

 

[jgreco]

Just to be pedantic, there's no reason 200MB/s+ isn't possible with a 5400 RPM drive. But point taken.

 

[TXAG26]

Agreed, it is surprising to see with these drives as they are behind a USB to SATA bridge which also does on-the-fly drive encryption. On some external drives, you may have to wipe and reformat these drives if you de-shell them or if the USB goes south as the encryption is built into the enclosure's USB-SATA bridge.

EDIT - the 8TB HGST's that were sold as WDC 8TB My Books did not have the encrypted USB-SATA bridge!

 

[Ericloewe]

Agreed, it is surprising to see with these drives as they are behind a USB to SATA bridge which also does on-the-fly drive encryption. Evidently, you have to wipe and reformat these drives if you de-shell them or if the USB goes south as the encryption is built into the enclosure's USB-SATA bridge.

Some of them can communicate with (probably proprietary) software to manage the encryption. Not that it's particularly interesting for the current use case, but it's worth noting for those who use them as USB-attached devices.

 

[jgreco]

I haven't de-shelled them yet, but they benchmarked identical to the PCPER article. One of my drives was actually a couple MB/s faster and one a mere 1 MB/s slower than the PCPER review. All within spec for USB 3.0. Well over 200MB/s+, which isn't obtainable with a 5400 rpm drive.

I got five of them. Haven't shucked them yet, but the same performance numbers and curve.

Interestingly enough there's some sort of USB SES device that shows up with each one, "WD SES Device 3002".

 

[Ericloewe]

Interestingly enough there's some sort of USB SES device that shows up with each one, "WD SES Device 3002".

Perhaps a byproduct of USB-attached SCSI. I'm not even sure what kind of support that thing has on the host side, but it seems that most new USB mass storage devices (other than crap flash drives) support it.

 

[jgreco]

Perhaps a byproduct of USB-attached SCSI. I'm not even sure what kind of support that thing has on the host side, but it seems that most new USB mass storage devices (other than crap flash drives) support it.

I see. It raised my eyebrows because it implies that there's additional capabilities there. It probably shouldn't be too shocking because at some point someone'll figure out that it is easier to do the whole bridge as a cheap SoC or something like that, and maybe that's just already happened and I don't buy enough USB disks to notice.