Will there ever be support for multiple parity drives?


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Also isn't RAID 6 "dual parity" by definition?

 

Yes.  But remember that "dual parity" is a misnomer -- it's used here to simply mean 2-drive fault tolerance; but implementing this does NOT mean there are simply two parity drives.    The mathematics is far more complex than a simple XOR'd parity drive for the 2nd layer of fault tolerance.    RAID-6 uses a Reed-Solomon code for the 2nd level of protection, but there are other techniques that can work as well.

 

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I seem to recall that discussion as well.    There are at least 3 different "schemes" I'm aware of, but I'm sure there are others.    I believe Tom plans to use one of the various "diagonal parity" schemes ... there are several ways to do this, and some of these are patented, so there are indeed likely to be licensing charges.    I'm sure the majority of UnRAID users would willingly pay a modest charge for this implementation which would more than cover the licensing charge  :)

 

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I seem to recall that discussion as well.    There are at least 3 different "schemes" I'm aware of, but I'm sure there are others.    I believe Tom plans to use one of the various "diagonal parity" schemes ... there are several ways to do this, and some of these are patented, so there are indeed likely to be licensing charges.    I'm sure the majority of UnRAID users would willingly pay a modest charge for this implementation which would more than cover the licensing charge  :)

 

Yes I would.

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I seem to recall that discussion as well.    There are at least 3 different "schemes" I'm aware of, but I'm sure there are others.    I believe Tom plans to use one of the various "diagonal parity" schemes ... there are several ways to do this, and some of these are patented, so there are indeed likely to be licensing charges.    I'm sure the majority of UnRAID users would willingly pay a modest charge for this implementation which would more than cover the licensing charge  :)

 

Yes I would.

 

+1

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  • 6 months later...

I'm sure the majority of UnRAID users would willingly pay a modest charge for this implementation which would more than cover the licensing charge  :)

 

Where do I sign?  ;)

Wait for unRAID 6.2 as we have been told that this includes support for dual parity.    What the licensing implications (if any) will be for the use of this feature I have no idea.

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I'm sure the majority of UnRAID users would willingly pay a modest charge for this implementation which would more than cover the licensing charge  :)

 

Where do I sign?  ;)

Wait for unRAID 6.2 as we have been told that this includes support for dual parity.    What the licensing implications (if any) will be for the use of this feature I have no idea.

That is excellent news, when  was this announced?

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I don't think it's been formally "announced" -- but in several discussions r.e. the dual parity feature it's been made clear that v6.2 is a TARGET for that feature.    Hopefully it will in fact be included at that point, but in any event it's definitely on the "list of coming attractions"  :)

 

Good to know.  I don't play on using dual parity until I add more disks to my array (Currently using just 4x 8TB drives so having half the disks be used for parity isn't desirable) but I will be adding more disks in the future and at that point it's something I'll definitely want to consider.

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  • 3 months later...

When the idea for dual parity was first brought I was super interested in it.  However, now that I have 8TB drives and I have a second server (that mirrors the first for backups) I personally don't think I'll ever move to dual parity.  For those that don't have proper back-ups I completely understand the need/desire for it though.  And since (from what I've personally witnessed) most people who run home servers don't seem to have proper backups I imagine this will be a widely popular feature.

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I'm also extremely interested in dual parity. After one of my friends had dual HDD failures due to having all seagates, I'm a little leery of my seagate drives. I've got 2 seagate and 2 toshiba(rebranded Hitachi). In my experience the Hitachi drives are the reliable way to go.

We know that dual parity is going to be a feature of the 6.2 release.
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I'm also extremely interested in dual parity. After one of my friends had dual HDD failures due to having all seagates, I'm a little leery of my seagate drives. I've got 2 seagate and 2 toshiba(rebranded Hitachi). In my experience the Hitachi drives are the reliable way to go.

We know that dual parity is going to be a feature of the 6.2 release.

Also, even before we get dual parity, unRAID v6.1 provides notifications of impending disk problems so it makes it much less likely that you will have these failures before you can address the problems. If you are still on v5 (this is the v5 support area) consider upgrading.
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  • 3 weeks later...

Howdy all,

 

Not, yet, an unRAID user... am actively shopping the alternatives.  Here is my core concern, one that if true would be total deal breaker for housing my growing music & video archive.  The folks over at SnapRAID claim:

 

"unRAID doesn't have any kind of checksum, and it just ignores silent errors. Even worse, if a parity error is detected as result of a silent error in the data, the parity is automatically recomputed, making impossible to recover the silent error, even manually."

 

I can find no information to refute, or support, that claim.... so here I be seeking a definitive answer; Is this claim true in v6.x ?

 

Cheers

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