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Find Cluster Size in Partitiion

Dealing with a data array of 24 physical disks. The controller is a MegaRaid/LSI/Avago 3108 firmware v24.9.0-0022. The physical disks are 500GB drives giving about 9TB.

Wanting to upgrade the storage space, I replaced the drives with 2 TB physical disks. This was done on-the-fly, 1-at-a-time so that the office was not disrupted. Fail disk, remove disk, insert new disk, let it re-raid. The process took about an hour a disk and I was able to complete over a few days.

With the new space available, I was able to grow the virtual-disk on the fly. Took about 8 hours to initialize.

With the disk space available, I wanted to expand the volume in Windows Disk Manager but got an error message:

"The volume cannot be extended because the number of clusters will exceed the maximum number of clusters supported by the file system."


Well, how many clusters do I have:

-type: fsutil fsinfo ntfsinfo f:


This shows that the cluster size is 4kb; this is the default-size.

As such, the official docs say that the max size is 16TB:

Cluster sizeLargest volumeLargest file
4 KB (default size) 16 TB 16 TB
8 KB 32 TB 32 TB
16 KB 64 TB 64 TB
32 KB 128 TB 128 TB
64 KB (maximum size) 256 TB 256 TB

The only way around this is to reformat the drive with a larger cluster size.


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