Windows Storage Spaces - 2 Way Mirror

Robert Spierenburg 1 Reputation point

Good morning Everyone,

We are running a small windows file server with two 4tb harddrives in a 2-Way Mirror storage space with ReFS. I have an extra 4tb harddrive that I was thinking of adding to the pool, but I was curious as to the benefits of adding a 3rd harddrive to the pool other than a little extra space. The current 4tb pool we have will be more than enough for us for the foreseeable future. Just wondering if we would gain speed or other benefits.

We don't have the room to add a 4th and 5th harddrive to move to a 3-Way Mirror. Would we be better off using that 3rd harddrive elsewhere?


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2 answers

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  1. Xu Gu (Shanghai Wicresoft Co,.Ltd.) 501 Reputation points Microsoft Vendor

    Hi Robert,

    For Two-way mirror and Three-way mirror, Two-way mirror is equivalent to having one data copy, while Three-way mirror has two data copies.
    The biggest difference between Two-way and Three-way is: Three-way mirror allows two disks to fail, but Two-way mirror only allows one disk to fail.
    Whether it is Two-way or Three-way, both have the effect of high availability, effectively perform failover, and ensure the security of data.
    For more information, please refer to the following links:

    Hope my answer can help you!

    Best Regards,
    Xu Gu

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  2. Robert Spierenburg 1 Reputation point

    As my original post stated, we don't have enough for a 3-way mirror (5 disks). I wasn't asking about the differences between 2-way and 3-way, I was asking what the benefits were to adding a 3rd disk to a 2-way mirror system.

    We ended up just using the 3rd harddrive as a hot spare in the 2-way mirror system.

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