Drive reliability for NAS... now questioning my original choice

[Sasqui]

great deal on 1 ... I tried to buy 4 and only save $16 total even though I saved $10 on 1 drive. I was kinda annoyed after that haha

With free shipping I wonder if you did multiple purchases you could use the code each time?

 

[copenhagen69]

With free shipping I wonder if you did multiple purchases you could use the code each time?

that is what I am going to try next ...

If not, I will just go amazon prime. 2 day shipping $165 total

 

[Uplink10]

That said, I'd shell out more for the WD Black series.

I would not, WD Black HDDs are too expensive especially for NAS.

Just me... rather have a reliable hard drive than more space or ram. I thought WD also makes and enterprise version of the red drives with 5-year coverage?

If you are using RAID you can afford less reliable drive and those enterprise drives start at 1.5x/2x the price of a consumer drives so it is better to buy consumer drive and because you are using RAID you are ready for HDD failure.
Backblaze tried this when 6TB HDDs were not yet available and it worked out good for them.

I think that you are all forgetting that if someone is using RAID he doesn't need to use the best HDDs (enterprise HDDs) available because using normal consumer HDDs is a lot cheaper in the long and short run.

I would use 3TBs HDDs because they have the lowest price per GB. I would use Toshiba DT01ACA300.

 

[copenhagen69]

@Uplink10

Why can't I find a warranty on the Toshiba? Is it warrantied?

 

[Uplink10]

Why can't I find a warranty on the Toshiba? Is it warrantied?

Of course it is, first warranty depends on your country laws so if you live in Europe you can bring the receipt to seller and they have to take care of it or you can just bring it to authorized service center and show them the receipt. Even if the warranty expired when they check serial number they still have to provide service because the warranty starts from the day you bought the drive and not the day the serial number "got activated".

 

[copenhagen69]

Of course it is, first warranty depends on your country laws so if you live in Europe you can bring the receipt to seller and they have to take care of it or you can just bring it to authorized service center and show them the receipt. Even if the warranty expired when they check serial number they still have to provide service because the warranty starts from the day you bought the drive and not the day the serial number "got activated".

True. But I'm not in EU I am in U.S. The stores normally offer a 90 day return policy but that's about it and the manus normally want you to return product to them and not the store.

 

[claes]

Toshiba drives have 2 year warranties for OEM/bulk and 3 years for retail.

If you are using RAID you can afford less reliable drive and those enterprise drives start at 1.5x/2x the price of a consumer drives so it is better to buy consumer drive and because you are using RAID you are ready for HDD failure.
Backblaze tried this when 6TB HDDs were not yet available and it worked out good for them.

Sure, but most consumers aren't setting up RAIDs with 45 drives in torturous 24/7 workloads with the kind of redundancy BB has in their poorly designed storage pods. For the average consumer this sort of cost analysis doesn't really make sense, particularly if they are using better hardware and aren't setting up a RAID 50/60 or similar.

Given the rate of disk failure in RAID rebuilds it makes a lot of sense for a consumer to be interested in high quality drives, having a hot spare, and having a proper backup system (RAID is not a backup!!!).

http://www.raid-recovery-guide.com/raid5-bad-rebuild.aspx

Moreover, most consumers aren't going to the trouble of changing firmware level settings on a drive to optimize for it NAS use (nor would they know where to begin), which is something BB can afford to do. For example, a lot of users were using WD Greens in RAIDs and experiencing incredibly high failures, while others would change park settings and have a stable NAS for years.

I think that you are all forgetting that if someone is using RAID he doesn't need to use the best HDDs (enterprise HDDs) available because using normal consumer HDDs is a lot cheaper in the long and short run.

Again, RAID is not a backup and RAID 5/6 have notoriously high failure rates during rebuilds (particularly with disks >1TB). If your drives aren't optimized for RAIDs (either OOB, like enterprise or NAS drives, or by hand by editing the firmware) you run an even greater risk of losing your whole array then you do already (unless, like BB, you have hundreds of spare disks of the exact same make and model that you can use at hot spares).

I would use 3TBs HDDs because they have the lowest price per GB. I would use Toshiba DT01ACA300.

Toshiba makes great drives but, again, I'd avoid 3TB drives due to their unusually high failure rates compared to their 2 and 4TB counterparts across brands, but if you can afford two spares on top of your redundant disk(s)...

Honestly, hardware RAID for consumers really doesn't make that much sense, particularly in terms of cost over time. IMO ZFS is the way to go for most home users.

EDIT: Also, just for the sake of being complete, looking at BB's latest numbers the Toshiba 3TB drive has the third highest failure rate with a sample of only 50. I've had good experiences with Toshiba but, again, it might be worth avoiding 3TB drives due to their unusually high failure rates.
https://www.backblaze.com/blog/best-hard-drive/
http://translate.google.com/transla...fr/articles/934-6/disques-durs.html&sandbox=1

 

[Uplink10]

Given the rate of disk failure in RAID rebuilds it makes a lot of sense for a consumer to be interested in high quality drives,

Again, RAID is not a backup and RAID 5/6 have notoriously high failure rates during rebuilds (particularly with disks >1TB).

I know RAID is not a backup but it is a lot better than having 3 drives in external enclosures which are not in RAID and connected directly to your PC in use. I currently have that setup and I am considering building NAS PC but to be fair I use them as cold storage and that means they are not constantly in use.
Failure rate during rebuild could be mitigated by using different drives by brand, age and batch and by using RAID 6 instead of RAID 5. But if you are using 3TB drives that also means that failure during rebuild is less likely to happen than if you were using drives with higher capacity because it takes longer to rebuild.

Honestly, hardware RAID for consumers really doesn't make that much sense, particularly in terms of cost over time.

I definetly agree, software RAID is more versatile (you are not limited to drives connected to specific controller in instance where you have more than one controller) and also free, if you are using Linux.

Toshiba makes great drives but, again, I'd avoid 3TB drives due to their unusually high failure rates

3TB drives have unusually higher failure rates but Toshiba DT01ACA300 does not have "that" high failure rate especially when you compare it to Seagate Barracuda 7200.14.

 

[claes]

RAID is really no better than having 3 external drives, unless you have a fourth and fifth drive to spare.

Failure rate can be mitigated in the way you are suggesting but if you look into the research this "mitigation" is in no way significant and relies on enterprise hardware to achieve even those middling improvements (ECC memory and Enterprise disks).

In the case of RAID 5, you'll want to keep two-three spares around - one hot-spare for your rebuild and at least a second for the inevitable rebuild failure. Mixing drives will not help much in this situation (it often leads to more problems here).

In the case of RAID 6, as you know, you're looking at three to four spare disks. Still, if one fails, you'll want to have a hot spare.

YOU DO NOT WANT TO RUN RAID 5 OR RAID 6 VIA SOFTWARE RAID. THIS IS A BAD, BAD IDEA AND SIGNIFICANTLY INCREASES FAILURES DURING REBUILD. You especially don't want to run an array (hard or soft) across different controllers.

Hardware RAID cards have dedicated ECC memory, battery back-up units, and their system is usually attached to a UPS - this is how they survive disk failures so well.

Point being that a proper RAID setup will cost a user a) $100 for a PERC + cables and BBU, b) $150 for a really low-end UPS, and c) not just three disks, but at least four (R5), if not five (R5+spare, R6), but, better, six (5 w/ two spares, 6 w/ one spare) or seven (6 w/ one spare). Then, if you choose to add capacity, you have to hope that your disk is still manufactured and buy another. THAT'S why it doesn't make sense for a consumer.

BB and other enterprises get away with RAID because they have 45 disks in an array in RAID50/60 or better. To match this sort of "security" for three disks worth of storage a user would have to buy 6-8 disks, plus some spares.

Even then, most data centers do not user consumer drives for all of the reasons above - if you want reliability, you pay for it. BB only uses consumer drives because they buy hundreds of disks at a time and are happy to throw them away after a couple of months.

ZFS, which is not software RAID, is an excellent middle-ground. While you'll want to pay for either ECC memory or a UPS, you don't have to buy a ton of disks at once, you can mix and match as you please, and you can add any disk at any time to any array whose controller has a port to spare.

BUT, all of this, still, is not a backup. Grab some external drives or an online backup service for redundancy because, eventually, disks fail!

 

[SuperSoph_WD]

Thanks for the reply!!

Yes I knew the basic differences but I just wanted to double check that there was nothing crazy like Pros must have at least 8 drives or they lose all hope and stop working ... maybe not that extreme but you know. Thanks for clearing that up!!

Also, any thoughts on this statement I found online ....

"I came out of an industry where the test results of solid state devices determined the warranty and price. I had a discussion with a Seagate Engineer and he said that if they guarantee a drive for 5 years, they only expect to have a very small percentage fail during the warranty."​

Is that a pretty accurate thought process in the industry?

Hi again, @copenhagen69

I'm sorry for the late reply! I will be off till the end of next week, so I had a lot of stuff to take care beforehand!

Though, I'm not exactly sure how to respond to this statement, I'm gonna give it a try! If a 5-year warranty is set for a product, there is only expected to be a small percentage of failures, but still nothing can be a 100% really. WD doesn't currently manufacture SSDs, but if the statement is referring to manufacturing IN GENERAL, then yes, pretty much all manufacturers do it the same way.

For example, a certain processor manufacturer has mentioned that they produce all their processors to be at their highest level (3GHz). After a batch of processors is manufactured, they then test them and see where they fall. The ones that hit the 3GHz are sold as their top of the line, the ones that fall into 2.8GHz fall into the lower bracket, then the 2.5GHz fall into the next lower bracket, and so on.

So I guess that statement could be accurate for most of the hardware industry.

SuperSoph_WD