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Any SATA HD drives which are <1 in 10^16 ? (notation for unrecoverable read error rate)

Question : I am wondering if there are any SATA hard drives available which are <1 in 10^16?

Why Asking : The blog-o-shpere is full of comments from 2013-2014 which indicate that Western Digital RE drives are <1 in 10^16. However, looking at the current pdf specs available on that unit, (November 2015) and it is <1 in 10^15. I was ready to purchase a dozen of these drives, but now I want to research other options.

Background : I am going to be building three parity arrays (RAID5) each array using four spindles at 4 or 5 TB each. With large capacity drives in RAID5, the URE rates really matter on a rebuild, and 10^14 quality drives are simply not a good idea. I am a big fan of RAID10., and understand the advantages of non-parity rebuilds/restores. But the cost per TB has me in the RAID5 camp for this particular build.

Thanks!
3 answers Last reply Best Answer
More about sata drives notation unrecoverable read error rate
  1. You can always go RAID6 for the extra layer of security without the full cost of RAID10. I looked at HGST and Seagate and their URE rates are listed as 10^15 also. I believe the commercial vendors (NetApp, EMC, etc) are OK with those specs.
  2. kanewolf said:
    You can always go RAID6 for the extra layer of security without the full cost of RAID10. I looked at HGST and Seagate and their URE rates are listed as 10^15 also. I believe the commercial vendors (NetApp, EMC, etc) are OK with those specs.


    1. Hi kanewolf, thanks for looking into Seagate and HGST options, it is greatly appreciated. RAID6 is awesome sauce but not an option for me.

    2. Trying not to bore anybody with the details of what I am trying to do here but essentially ...cant do RAID6 internally (On my Mac Pro 5.1 with 4 internal drive bays) because I'm not using a Raid card, I'm using SoftRaid which does not support RAID6. My two external boxes will give me RAID options via a hardware switch, but those options are JBOD, RAID0, 1, 5, 10. One external Box for incremental hourly backups. The second external box I will update once per week and keep offsite for theft or fire insurance. Not building a data center NAS. I run a Retouching-CGI-Animation business from one workstation, and have 15 years worth of archives, and several TBs of current work at any given moment.

    Thanks again for your assistance ;)
  3. Best answer
    If WD, HGST, and Seagate "only" support 10^15 then I guess you REALLY don't have a choice. Might be time to replace at least one of those external boxes with RAID6 compatible HW. Backblaze has some very interesting blog posts about drive reliability. Generally, if you get past the infant mortality then you have about a 5 year stable lifespan, which correlates to the warranty length for enterprise drives.
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