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Who Makes the Best Hard Disk Drives?
Hamsterdan writes "Backblaze, the cloud backup company who open sourced their Storage Pod a few years ago, is now providing information on drive failure rates. They currently have over 27,000 consumer grade drives spinning in Backblaze storage pods. There are over 12,000 drives each from Seagate and Hitachi, and close to 3,000 from Western Digital (plus a too-small-for-statistical-reporting smattering of Toshiba and Samsung drives). One cool thing: Backblaze buys drives the way you and I do: they get the cheapest consumer-grade drives that will work. Their workload is almost one hundred percent write. Because they spread the incoming writes over several drives, their workload isn't overly performance intensive, either. Their results: Hitachi has the lowest overall failure rate (3.1% over three years). Western Digital has a slightly higher rate (5.2%), but the drives that fail tend to do so very early. Seagate drives fail much more often — 26.5% are dead by the three-year mark."
For the past 11 years, I used nothing but Seagate drives in my builds for clients. Over those past 11 years, I built something like 20 systems a month (on average) with occasional large scale orders of 200. The number of failed Seagates I could count *on one hand* YMMV clearly, but I stand behind Seagates.
So rise up, all ye lost ones, as one, we'll claw the clouds.
Disclaimer: I work at Backblaze. I object to the marketing term "Enterprise grade", it is confusing, and I'm not even sure they have the attributes you think they have. There is a completely different blog post Backblaze did about "Enterprise vs Consumer Drives" which comes to the conclusion Enterprise isn't better: http://blog.backblaze.com/2013...
They're looking for 4TB models. They only cite two models without any further information.
Seagate ST4000DM000
vs
Hitachi HDS5C4040ALE630
You can look up technical details, benchmarks, etc. but perhaps the decision is simply in the price.
Seagate: $164.99
Hitachi: $295.00
For the Hitachi model to start making sense, price-wise, that Seagate model would have to fail a lot more than their numbers are currently showing,
( And yes, I'd imagine they can squeeze better deals than regular consumer prices out of the companies - but then, they could do that for either brand, and probably through an intermediary anyway. )
Are you sure about 5TB drives being available on Amazon for a couple hundred dollars? I didn't think Western Digital had released those yet and their website shows 4TB as the max capacity for their Green, Black and Red series drives and Amazon doesn't have any listings for 5TB drives? If they are available can you share a link?
After all this research, Backblaze still pick the highest failing drive.
Disclaimer: I work at Backblaze. Every month we ask a list of about 20 suppliers for their best price on a variety of drives. There is a little spreadsheet we have that kicks out which drive to purchase based on those prices and drive failure rates. Even if Hitachi is the very highest reliability in our application, it only justifies a SMALL price premium because when one drive dies, we don't lose any customer data. It saves our datacenter IT team 15 minutes to *NOT* swap a drive, so that's worth 15 minutes of salary to us, but not more.
If you RTFA, they break down the failure rates by model (no pun intended). There's a pretty huge variation between models (or at least the Seagate models). That's also what I saw in the StorageReview reliability database back when people were actively updating it (unfortunately you have to add a drive to the database to get access to it, so it was never very popular). The same manufacturer can make a gem and a stinker of a model. e.g. the IBM 75GXP (aka Deathstar) drives had one of the highest failure rates in the database. The drive which replaced it (60GXP I think) had one of the lowest failure rates in the database.
So it's more nuanced than "Seagate stinks, Hitachi rules." (Hitachi is a subsidiary of WD now, operating separately only because that was a condition China placed on them before they'd OK the merger.)
NewEgg doesn't sell any 5TB drives, internal or external, and nobody makes them either (yet), so... no you can't?
This is why you just buy whatever is cheap and rig up a RAID 5. A drive craps out and you throw another one in and keep on going.
RAID-5 on a system where you don't think you have high quality drives, a high quality power supply, battery backup (for the RAID card) plus a high quality UPS unit (preferably multiple UPS units hooked up to a set of redundant PSUs inside your case) -- is simply a bad idea. Sooner or later, you *will* lose the array due to a double-drive failure. Oh and make sure that you have plans to swap out drives on a regular basis and have a working backup plan.
RAID-6 is better, but not by much. It can at least deal with a double drive failure. But performance still goes in the gutter while it's degraded and/or rebuilding.
One of the more fault-tolerant setups is a 3-way RAID-1 mirror where you can lose 2 of 3 drives without losing data. The downside is that it is only 33% efficient while RAID-6 (1 spare, 2 parity, 5 data) is 62% efficient. A well configured RAID-10 setup also works well, but never gets much above 40-45% space efficiency if you set aside a hot spare for it.
Main reason why I prefer RAID-10 for larger arrays is that the time to rebuild a failed disk is linear to the size of a single disk within the array (because you have mirror pairs). With RAID-5 / RAID-6 the rebuild time scales with the total size of the array. For a 15-20 drive array, that means RAID-10 could rebuild the failed drive in 1/5 to 1/10 the time of the RAID-5 or RAID-6 array with the same number of spindles.
Wolde you bothe eate your cake, and have your cake?
And in the last 25 years I've replaced about 200 failed drives. The Maxtors failed at about 5x the rate of the Seagates. That shows you want ancidotal evidence is worth.
To know actual reliability, you need stats on the level of Google or Amazon, that can tally failures by the 10's of thousands.
I searched on 4+ comments, and didn't see anything, so here is Google's study> (they go through a lot of drives)
I have RAID 5 with 4 x 3TB seagate drives. 1 drive failed after a year and the 2nd in the same NAS failed a couple of days later before a replacement could come in the post. So far 3 / 8 Barracuda drives failed in just over 1 year. After just losing 4TB of data, including my entire photo collection, I've sadly realised RAID 5 isn't enough.
Phillip.
Property for sale in Nice, France