Storage Spaces Dual Parity

danielgrey

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I have Windows 8, my OS is on a separate drive and I have placed 8x2tb drives into storage spaces parity. I wanted to use dual parity. No option for dual parity came up and windows did not automatically build a dual parity, as far as I'm aware.

Storage Pool says using 10TB of 14.5TB
Drive Tools says 7.82TB free of 14.4TB
Properties says Used space 6.67 Free space 7.82

I'm interested to know if I'm already using Dual Parity or if I'm not how to get the option to use it? Ive done a great deal of searching on the net for an image of the option. Or concrete proof that someone else is using the option and have found none.
 
The only thing that caught my attention besides the references to Windows Server 2012 is somewhat of a kinship to RAID.
A link on Storage Space Internal | Windows Server 2012 content from Windows IT Pro took me to
Storage Spaces - Designing for Performance - TechNet Articles - United States (English) - TechNet Wiki


I thought it was interesting it said "It is also possible to use dual-parity in Windows Server 2012 R2" in the first link

Which may mean you can't use dual parity in Windows 8

Your links gave me the idea to type "
dual parity only on server" into google which found this link https://social.technet.microsoft.co...-creating-a-virtual-disk?forum=winserverfiles

Which is someone else asking the same question but as close as Ive come to answer to. Does Windows 8 have Dual Parity?
 
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Thanks for clearing this up. Do you recommend using Dual Parity for 8x2TB hdd?

I've heard that raid 5 is not recommended for more than 5 HDD because of the likely hood of an error during rebuild. I've also heard that Parity on Windows 8 is not Raid5 but I would like to know if I'm likely to experience any errors.
 
Hi there

Storage spaces work just great -- and you don't need to use the same size HDD's either. I wouldn't have 8 in the mix --although it depends on the size you want to create -- it might be better for example to create TWO pools of 4 X 2 TB.

Parity is fine -- unlike mirroring you only need 1/2 of the space that a full mirror uses ("Striping").

Depending on what you need the space for you could even risk having no redundancy at all. I have data space of my multi-media files with no redundancy. My Multi-media set doesn't change much and I have an archive set in case of trouble. HDD's are fairly robust these days and newer ones don't normally suddenly fail.

Incidentally if you start with a smaller storage space you can ADD volumes later if you need more space so you don't have to allocate the whole set of 8 X 2 TB in the beginning.

For shared / remote computers / LAN the storage space appears as a Single Drive so sharing is handled quite normally.

RAID requires ALL volumes to be the same size. Storage spaces are much more flexible. You can of course use full mirroring if you want but it's not normally necessary.


Read the link again it's quite helpful.

Storage Spaces: FAQ - Windows Help

Cheers
jimbo
 
Thanks for the info. I have 8x2tb drives and I will be storing a large amount of video footage indefinitely. I want the safest option for storing my clients footage.

I have read that raid 5 fails during rebuilds when using a lot of HDDs. I'm assuming Single Parity on storage spaces is similar to Raid5.

I'm not interested in using raid5. I am worried about losing all my data during a storage space parity rebuild from a failed drive. Would I be better off switching to Windows Server2012 Dual Parity because I'm using 8 HDDs? Are you saying I should switch to two lots of 4x2tb instead of one 8x2tb?

Thanks again for your help Jimbo. If this seems like a double post I'm re wording my question here because it seemed like you were telling me the benefits of storage spaces vs raid and not answering my question. My apologies if I have misunderstood.
 
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Now By no means am I an expert, but I do believe it says you can have/use a dual parity on storage spaces, look under the "New and changed functionality section." https://technet.microsoft.com/en-us/library/hh831739.aspx

Thanks for replying wmechnig. You're right you can use dual parity on storage spaces but only in Server 2012. If you get a chance to reply to my follow up questions please do.

So turns out dual parity would of been of great benefit to me if it had been available in Windows 8. I had a single drive fail (1 of 8) Storage Spaces kept working as it should. The next time I turned on the computer, it said reduced resiliency. I went into SS, it was rebuilding. Unfortunately it went through the rebuilding process every time I turned on the computer. Never getting past reduced resiliency which meant copying files off the SS would transfer at a blistering 700kb/s. So I couldn't save the 10 TB/s of data from SS unless I had a spare 2 years. A few hours later one of the drives was listed as Stale, enable pool. With no options to do anything to fix a stale disk in SS, or find any steps to take in google. Soon the stale drive moved to a disconnected stage then an unused stage asking to be removed and Storage Spaces became inaccessible. Next step is to replace the failed drive and hope. It does make me wonder if Parity is feasible for groups of 7 or more 2TB+ Disks.
 
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Thanks for the info. I have 8x2tb drives and I will be storing a large amount of video footage indefinitely. I want the safest option for storing my clients footage.
If you get nothing else from this post, make sure that you remember this: RAID and/or STORAGE SPACES are not a substitute for backups. RAID is redundancy for your hard drives, but should never be a substitute for proper backups.

The safest option without question is to make multiple backups, and keep those backups offsite.

have read that raid 5 fails during rebuilds when using a lot of HDDs. I'm assuming Single Parity on storage spaces is similar to Raid5.
When you have a RAID array that contains any type of parity, when a drive fails and is replaced, you put a good amount of wear and tear on all of the remaining drives when they read the data and parity and rebuild the array. Since all of the drives will be working hard during a rebuild, it is during this time that you have the most risk of a drive failure. It has nothing to do with the # of drives however...other than if you have 10 drives, versus 5 drives, you have more drives that "could" potentially fail.

As far as safety goes, and speed goes a RAID 10 is the best option. With a RAID 10 you get the speed benefits of the stripe without the write penalty involved with having parity. However, the downfall is that you only get 1/2 of your raw space as usable with RAID 10. But you can have multiple hard drive failures in a RAID 10 without catastrophic loss, as long as they are NOT both members of the same stripe. For example, drives 1-2, 3-4, 5-6, 7-8, 9-10. You could have #1 fail, #3 fail, #6 fail, #8 fail and #9 fail and you could still keep going. You just cannot have drives #5 and #6 fail at the same time or you lose that section of the stripe. Make sense???
 
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