Win10 Storage Spaces Question

[PineyCreek]

Silly, potentially simple questions:

 

I have two 5 TB drives running in two-way mirror configuration using Windows Storage Spaces (aka software RAID 1).  If I added a third drive, is it possible to get a RAID 5 equivalent using WSS?  I need more space but I don't want to give up the redundancy.

 

If it's possible, would I need to break the two-way mirror, or could WSS transition directly from software RAID 1 to something different?

 

Finally, does WSS care about using different size drives?  Ex, could I get a 6 TB drive instead of a 5 TB?

[Timothy11]

To create a Parity (raid 5) Storage space you will have to ...

• Add a new disk to the Storage Pool
• Create a new Storage Spaces on the Pool that using Parity
• Copy the data from the Old Storage Space to the new Storage Space (Will run into issues if the existing space is using too much of the Pool's space as you will need enough space to have the data on both the Old Storage Space and the New Storage Space at the same time).
• Delete the Old Storage Space.

If you do not have enough space to copy the data from the Old Storage Space to the New Storage Space You could back up to a NAS or external drive and then restore from there.

 

Also note that if you are not using a SSD's as a write cache, writing to a Parity Storage space is very slow 30-50 MB/s (With a SATA SSD cache you can get burst write speeds of over 1 GB/s).

Edited October 14, 2017 by Timothy11
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[PineyCreek]

34 minutes ago, Timothy11 said:

To create a Parity (raid 5) Storage space you will have to ...

• Add a new disk to the Storage Pool
• Create a new Storage Spaces on the Pool that using Parity
• Copy the data from the Old Storage Space to the new Storage Space (Will run into issues if the existing space is using too much of the Pool's space as you will need enough space to have the data on both the Old Storage Space and the New Storage Space at the same time).
• Delete the Old Storage Space.

If you do not have enough space to copy the data from the Old Storage Space to the New Storage Space You could back up to a NAS or external drive and then restore from there.

 

Also note that if you are not using a SSD's as a write cache, writing to a Parity Storage space is very slow 30-50 MB/s (With a SATA SSD cache you can get burst write speeds of over 1 GB/s).

Almost sounds like it would be a better idea to switch to on-board RAID or copy off data to disc or external hard drive that I don't need the redundancy for.  I'm not terribly inclined to get another SSD to use as a write cache, unless I can use a portion of an existing SSD (which is not part of the current WSS setup) as a write cache for this new parity storage space.

[Timothy11]

5 hours ago, PineyCreek said:

Almost sounds like it would be a better idea to switch to on-board RAID or copy off data to disc or external hard drive that I don't need the redundancy for.  I'm not terribly inclined to get another SSD to use as a write cache, unless I can use a portion of an existing SSD (which is not part of the current WSS setup) as a write cache for this new parity storage space.

The SSD will need to be just for the Storage Pool, but can be used for multiple Storage Spaces on the pool.
For example I have three spaces all on the same pool that has 3 3TB HDD and 2 120GB ssd. One space for games (Raid 0), one for important data (Raid 1, this splits across 3 disks fine so you should be able to just add one disk to your pool and run the Optimize drive usage, this will give you 7.5TB of usable space but it you can use parity it will give you 10TB), one for large storage (Raid 5). All of these spaces use the same ssd as a write cache.

 

 

It is worth noting that you will need two ssd drives for the cache if you are using a redundant storage as the cache for a redundant storage also has to be redundant (raid 1).