Windows 8 adds RAID-like storage pooling and fault tolerance

Rick

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An interesting article has been posted to the MSDN blog, thoroughly outlining a new Windows 8 feature called "Storage Spaces". The technology will allow users to create a single storage volume from multiple storage devices. The feature also allows users to dynamically expand a Storage Space volume by adding more devices on the fly. Storage Spaces affords users this freedom by cleverly organizing used and free space across NTFS volumes. 

For example, Windows 8 users will be able to lump together any mixture of storage devices into a single volume that appears as D:\. If a user gets low on space, they can simply pop in another hard drive or plug in another external drive and Storage Spaces will expand D:\ to include the new device. More importantly, it does this without losing data.

Storage Spaces allows NTFS-formatted devices to be combined into "pools" and broken apart into "spaces". Pools are collections of storage devices that work similarly to JBOD RAID arrays (just a bunch of disks) while spaces are more analogous to partitions. Unlike JBOD arrays though, the feature also protects your data from drive failure. Similar to RAID 5, Storage Spaces utilizes parity data to provide a fault tolerance strategy.

Although they share a lot of common ground though, Storage Spaces is not a RAID solution. The FAQ states:

Fundamentally, Storage Spaces virtualizes storage in order to be able to deliver a multitude of capabilities in a cost-effective and easy-to-use manner. Storage Spaces delivers resiliency to physical disk (and other similar) failures by maintaining multiple copies of data. To maximize performance, Storage Spaces always stripes data across multiple physical disks. While the RAID concepts of mirroring and striping are used within Storage Spaces, the implementation is optimized for minimized user complexity, maximized flexibility in physical disk utilization and allocation, and fast recovery from physical disk failures. Given these significant differences in objectives and implementation between Storage Spaces and traditional inflexible RAID implementations, the RAID nomenclature is not used by Storage Spaces.

Currently, hardware and software technologies which offer similar benefits do exist, such as LVM, ZFS, Drobo, higher-end RAID controllers and so on. However, Storage Spaces appears to offer a great deal of flexbility and simplicity, simultaneously. The feature is, at the very least, a huge improvement over the current implementation of "Dynamic Disks" found in Windows.

Storage Spaces will effectively be the "consumer" version of Drive Extender, a deprecated feature of Windows Home Server. However, the blog points out it is not intended to be a feature-by-feature replacement and is incompatible with existing Drive Extender volumes.

Permalink to story.

 
Doesn't make a lot of sense to me.
Didn't they take this out of Windows Home Server 2011?
Why add it to Windows 8 then?
I still use Home Server 2007 because of this issue.
 
The windows home server feature was not exactly this, but similar. It makes a lot of sense. People are in great need of space with the large media collections they are starting to gather. Be glad to get a pro or business feature. I might not even be in a Home Premium version... but might be in a professional version. They still have not given details to the different flavors Windows 8 will come in...

I welcome this feature if it works properly and provides a robust option for me to expand my data storage on site.
 
This is a great idea, about 10+ years too late with the large drive capacities, ubiquitous motherboard and add-in Raid solutions, not to mention ubiquitous and cheap external consumer NAS arrays.

This is typical of Microsoft, they jealously guard features they think are high-end in their server and ultimate versions and lock them out of the 99% of the windows using population for profit motives, until the rest of the world moves on with cheap and free alternatives, then Microsoft suddenly realizes what a good idea it would have been to have had this all along.
 
"This is typical of Microsoft"

you mean adding additional functionality features for profit? *shocker!*
Ii thought they made software for free as in free beer.
 
"While the RAID concepts of mirroring and striping are used within Storage Spaces, the implementation is optimized for minimized user complexity, maximized flexibility in physical disk utilization and allocation, and fast recovery from physical disk failures. Given these significant differences in objectives and implementation between Storage Spaces and traditional inflexible RAID implementations, the RAID nomenclature is not used by Storage Spaces."

Sounds good to me. Traditional "raid 5" FAILS if 2 or more disks are defective in the stripe, which is not so uncommon as you think. This sounds similar to raid "n" which overcomes this.
This is not the same as your typical raid or cheap nas solution.
 
Well not that Apple doesn't do the same thing. At least Microsoft doesn't make their solution compatible only with their proprietary hard drives or interface. I would buy one of the new 27in iMacs as I like a lot about them, but whoops - the only fast storage connection is thunderbolt, and you can't use it for an external monitor for anything but another mac with thunderbolt.
 
Windows 7 already already effecitively includes "pooling". I have added 3x 2Tb drives as a single drive for a while I was just using 2x2Tb and expanded this recently. I also tested reducing it and that works aswell. They show up in the system as "Spanned Volume"
 
Emexrulsier said:
Windows 7 already already effecitively includes "pooling". I have added 3x 2Tb drives as a single drive for a while I was just using 2x2Tb and expanded this recently. I also tested reducing it and that works aswell. They show up in the system as "Spanned Volume"

When I was reading the story I was thinking the same thing but couldn't be bothered to comment.
I agree though, this feature pretty much exists in windows 7, just doesn't have quite as flashy GUI as Windows 8 has given it.
 
Emexrulsier said:
Windows 7 already already effecitively includes "pooling". I have added 3x 2Tb drives as a single drive for a while I was just using 2x2Tb and expanded this recently.
Existing support in Windows for "storage pooling" is based on JBOD. It's definitely not the same thing though, although pooling does exist.

JBOD provides NO fault tolerance. This is an essential difference as Storage Spaces implements parity checking.

Storage Spaces also allows users to assign hot swap spares (mentioned in the article) for increased reliability and obviously sports a prettier interface. There are a number of other subtle features too. I recommend checking out the FAQ in the link... very informative.
 
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