The mmwindisk command

On Windows nodes, use the mmwindisk command to view all disks known to the operating system along with partitioning information relevant to GPFS.

For example, if you issue mmwindisk list, your output is similar to this:
Disk Avail Type    Status    Size     GPFS Partition ID
---- ----- ------- --------- -------- ------------------------------------
   0       BASIC   ONLINE     137 GiB
   1       GPFS    ONLINE      55 GiB 362DD84E-3D2E-4A59-B96B-BDE64E31ACCF
   2       GPFS    ONLINE     200 GiB BD5E64E4-32C8-44CE-8687-B14982848AD2
   3       GPFS    ONLINE      55 GiB B3EC846C-9C41-4EFD-940D-1AFA6E2D08FB
   4       GPFS    ONLINE      55 GiB 6023455C-353D-40D1-BCEB-FF8E73BF6C0F
   5       GPFS    ONLINE      55 GiB 2886391A-BB2D-4BDF-BE59-F33860441262
   6       GPFS    ONLINE      55 GiB 00845DCC-058B-4DEB-BD0A-17BAD5A54530
   7       GPFS    ONLINE      55 GiB 260BCAEB-6E8A-4504-874D-7E07E02E1817
   8       GPFS    ONLINE      55 GiB 863B6D80-2E15-457E-B2D5-FEA0BC41A5AC
   9 YES   UNALLOC OFFLINE     55 GiB
  10 YES   UNALLOC OFFLINE    200 GiB
Where:
Disk
is the Windows disk number as shown in the Disk Management console and the DISKPART command-line utility.
Avail
shows the value YES when the disk is available and in a state suitable for creating an NSD.
GPFS Partition ID
is the unique ID for the GPFS partition on the disk.

The mmwindisk command does not provide the NSD volume ID. You can use mmlsnsd -m to find the relationship between NSDs and devices, which are disk numbers on Windows.