Exam AZ-800 topic 5 question 17 discussion

2 and 5 https://learn.microsoft.com/en-us/training/modules/implement-storage-spaces-storage-spaces-direct/2-define-storage-spaces-architecture-components Resiliency levels To create a highly available virtual disk, you need at least one physical disk that satisfies the following requirements: 1.One physical disk is required to create a storage pool. 2.A minimum of two physical disks are required to create a resilient mirror virtual disk. 3.A minimum of three physical disks are required to create a virtual disk with resiliency through parity. 4.Three-way mirroring requires at least five physical disks. 5.Disks must be blank and unformatted. No volume can exist on the disks.

To create a storage pool with a mirror layout, let’s explore the minimum disk requirements for both two-way and three-way mirrors: Two-Way Mirror: A two-way mirror provides redundancy by maintaining two copies of data. The minimum number of disks required for a two-way mirror is two. It ensures fault tolerance against a single disk failure. Three-Way Mirror: A three-way mirror enhances redundancy by maintaining three copies of data. The minimum number of disks required for a three-way mirror is five. It provides additional fault tolerance, allowing for two simultaneous disk failures.

I can see the answer for three-way mirror is 5 but can anyone explain why under this link it says you only need 3? https://learn.microsoft.com/en-us/azure-stack/hci/concepts/fault-tolerance#minimum-scale-requirements

Resiliency levels To create a highly available virtual disk, you need at least one physical disk that satisfies the following requirements: One physical disk is required to create a storage pool. A minimum of two physical disks are required to create a resilient mirror virtual disk. A minimum of three physical disks are required to create a virtual disk with resiliency through parity. Three-way mirroring requires at least five physical disks. Disks must be blank and unformatted. No volume can exist on the disks. You can attach disks by using a variety of bus interfaces, including, small computer system interface (SCSI), Serial Attached SCSI (SAS), Serial ATA (SATA), NVM Express (NVMe).

as per exam dump.. its says.. 1, 1

https://learn.microsoft.com/en-us/training/modules/implement-storage-spaces-storage-spaces-direct/2-define-storage-spaces-architecture-components A minimum of two physical disks are required to create a resilient mirror virtual disk. A minimum of three physical disks are required to create a virtual disk with resiliency through parity. Three-way mirroring requires at least five physical disks. Answer is correct

Three-way mirroring requires a minimum of 5 disks, while two-way mirroring requires a minimum of 2 disks. With three-way mirroring, data is written to three separate disks, which provides more data protection and redundancy in the event of disk failure.

Given answer is correct https://social.technet.microsoft.com/Forums/en-US/827d7b90-87bf-4bcb-9f06-f6c4a5c31b8f/storagepool-minimum-disk-requirement-for-two-way-and-three-way-mirror?forum=winserverfiles

This really is a dumb question - you never have a single server pool- but i suppose this is good for academic question. = - Use the storage calculator and play with the numbers - you will see the 2 for two way and 5 for 3 ways is correct- only when you hit 5 drives and 4 nodes- do you see the three mirror for the first time- https://s2dcalc.blob.core.windows.net/www/index.html https://blog.sqlxdetails.com/capacity-calculator-for-storage-spaces/

Answer is correct according to https://www.pcmag.com/how-to/how-to-combine-multiple-hard-drives-with-windows-storage-spaces#:~:text=Two%2DWay%20Mirror%20and%20Three,three%2Dway%20mirror%20requires%20five.

Three-way mirror—this option writes three copies of stored data, requiring at least five disks, and will protect against a two-disk failure. https://www.pearsonitcertification.com/articles/article.aspx?p=2014559

I searched but didn't find the reason why this answer shows 5 required for three-way mirror

Incorrect Should be 2/3 https://docs.microsoft.com/en-us/azure-stack/hci/concepts/fault-tolerance

Correct