Storage Space direct cluster colum Count confusion

Abdul Baba Syed 21 Reputation points
2020-09-16T05:17:24.037+00:00

I have 3 nodes, joined to cluster and created storage space and a volume..

Each node has 3 HDD disks, each 1 TB and created a volumes

look at the image, why 1gb size is taken as 3.94 GB and column count is 4,
i have only 3 disk per node, how it is taking 4 column, it should be 3 column right.. as 4 columns exceeds 3 disk in one node.
and resillency here is mirror..

As per microsoft, if you have 3 node cluster, it will be considered as Three way mirroring..im not sure, how to prove this to the customer..

and why a volume of 100 gb is take as 99.94 gb

25103-image.png

25112-image.png

25113-image.png

Request you to clarify.. Thanks

Windows Server Storage
Windows Server Storage
Windows Server: A family of Microsoft server operating systems that support enterprise-level management, data storage, applications, and communications.Storage: The hardware and software system used to retain data for subsequent retrieval.
631 questions
0 comments

2 answers

Sort by: Most helpful
Most helpful Newest Oldest
  1. Daniel Zhou (Shanghai Wicresoft Co,.Ltd.) 256 Reputation points
    2020-09-17T07:08:13.74+00:00

    Hi,

    You can check the resiliency type to see if it is a two-way or three-way.
    100g is only a theoretical size. In fact, the disk metadata and some configuration files also take up part of the space, so this is a normal phenomenon
    For more question about this, please check:
    https://social.technet.microsoft.com/wiki/contents/articles/11382.storage-spaces-frequently-asked-questions-faq.aspx#What_are_columns_and_how_does_Storage_Spaces_decide_how_many_to_use

    Best Regards,
    Daniel

    0 comments
  2. Abdul Baba Syed 21 Reputation points
    2020-09-18T13:24:43.97+00:00

    Thanks.. Sorry I have to unaccepted, still not clear

    I have added total 7 disk each node, total nodes 3 nodes.. Total disk 21 disk in cluster/s2d

    For eg: Creating 1 gb volume

    New-Volume -FriendlyName "1gb" -FileSystem CSVFS_ReFS -StoragePoolFriendlyName S2D* -Size 1GB -ResiliencySettingName Mirror -PhysicalDiskRedundancy 2 -NumberOfColumns 7

    DriveLetter FileSystemLabel FileSystem DriveType HealthStatus OperationalStatus SizeRemaining Size

    1gb CSVFS Fixed Healthy OK 6.22 GB 6.94 GB

    I understand, there is a column colunt of 7 so it took almost 7 GB

    25823-image.png

    But when i Create 100 GB, why it is not creating 700gb, based on the column 7

    25787-image.png

    25748-image.png

    25749-image.png

    Both the drives are 3 way mirroring as NumberofDatacopies is 3

    My question why 1 gb volume is showing as 7 gb volume
    and why not 100 gb volume should show as 700gb volume..

    Is im missing anything..

    0 comments