How to name a partition for zpool create?

[Erwin53]

I have a laptop with only one disk, so Windows uses several partitions and at the "end" there is a big (raw) partition I would like to use to create a ZFS Pool. How do I specify this partition in a "zpool create" command (as opposed to something like \?\PHYSICALDRIVE1)?

Erwin

[lundman]

https://github.com/openzfsonwindows/openzfs/blob/zfs-Windows-2.3.0-release/lib/libzutil/os/windows/zutil_import_os.c#L1157

Looks like HarddiskXPartitionY. You can create a pool in a file too, if you are just playing. Either a file on disk, or as a vhdx mounted as a disk.

[Erwin53]

Thanks for the quick answer. Currently, I use the partition to create a Windows Storage Pool in it thus providing thin provisioning for my Windows volumes. Using ZFS I would not need this anymore.

It sort of works but gives an error message although the pool is successfully created:

PS C:\> diskpart

Microsoft DiskPart-Version 10.0.22621.1

Copyright (C) Microsoft Corporation.
Auf Computer: XXXXXX

DISKPART> list disk

  Datenträger ###  Status         Größe    Frei     Dyn  GPT
  ---------------  -------------  -------  -------  ---  ---
  Datenträger 0    Online          511 GB   234 GB        *
  Datenträger 1    Online          127 GB      0 B        *

DISKPART> sel disk 0

Datenträger 0 ist jetzt der gewählte Datenträger.

DISKPART> list part

  Partition ###  Typ               Größe    Offset
  -------------  ----------------  -------  -------
  Partition 1    Reserviert          15 MB    17 KB
  Partition 2    System             260 MB    16 MB
  Partition 3    Reserviert         128 MB   276 MB
  Partition 4    Wiederherstellun  1024 MB   404 MB
  Partition 5    Primär             150 GB  1428 MB
  Partition 6    Primär              20 GB   151 GB
  Partition 8    Primär            5120 MB   176 GB
  Partition 9    Primär             100 GB   181 GB

DISKPART> exit

Datenträgerpartitionierung wird beendet...
PS C:\> zpool list
no pools available
PS C:\> zpool create -O casesensitivity=insensitive -O normalization=formD -O compression=lz4 -O dedup=on -O atime=off -o ashift=12 -o autotrim=on tpool '\\?\Harddisk0Partition9'
working on dev '\\?\Harddisk0Partition9'
setting path here '/dev/Harddisk0Partition9'
setting physpath here '\\?\Harddisk0Partition9'
cannot open '/dev/Harddisk0Partition9': No such file or directory          <================
PS C:\> zpool list
NAME    SIZE  ALLOC   FREE  CKPOINT  EXPANDSZ   FRAG    CAP  DEDUP    HEALTH  ALTROOT
tpool  99.5G   532K  99.5G        -         -     0%     0%  1.00x    ONLINE  -
PS C:\> zfs list
NAME    USED  AVAIL  REFER  MOUNTPOINT
tpool   436K  96.4G   100K  /tpool
PS C:\>

Cheers,
Erwin

[copyliu]

but I can't zpool add pool HarddiskXPartitionY

it return

Expanded path to '\\?\Harddisk3Partition0'
cannot use 'Harddisk3Partition0': must be a block device or regular file

[Erwin53]

You could use DISKPART to get the partition number:

DISKPART> list disk

  Datenträger ###  Status         Größe    Frei     Dyn  GPT
  ---------------  -------------  -------  -------  ---  ---
  Datenträger 0    Online         1863 GB    93 GB        *
  Datenträger 1    Online         1863 GB   140 GB        *
  Datenträger 2    Online         4096 GB  2450 GB        *
  Datenträger 3    Online          120 MB      0 B

DISKPART> sel disk 0

Datenträger 0 ist jetzt der gewählte Datenträger.

DISKPART> list part

  Partition ###  Typ               Größe    Offset
  -------------  ----------------  -------  -------
  Partition 1    Reserviert          15 MB    17 KB
  Partition 2    Primär            1763 GB    16 MB
  Partition 3    Primär            7013 MB  1763 GB

DISKPART>

[lundman]

Powershell

Get-Partition | ForEach-Object { 
    [PSCustomObject]@{
        Path       = "\\?\Harddisk$($_.DiskNumber)Partition$($_.PartitionNumber)"
        Size       = "$($_.Size) bytes"
        AccessPath = ($_.AccessPaths -join ", ")
    }
} | Format-Table -AutoSize

The partition numbers never match what I think they should.

[sskras]

Cool! That could go into README, wiki or something. :)

[lundman]

wiki yes, i never have time though :)

[guenther-alka]

or for a disk like physicaldrive 1
Get-Disk -Number 1 | Get-Partition

[sskras]

And maybe simply Get-Partition, if a user isn't sure about the disk number:

PS C:\Users\saukrs> Get-Partition


   DiskPath: \\?\scsi#disk&ven_nvme&prod_samsung_ssd_980#5&2eacfa49&0&000000#{53f56307-b6bf-11d0-94f2-00a0c91efb8b}

PartitionNumber  DriveLetter Offset                                        Size Type
---------------  ----------- ------                                        ---- ----
1                           1048576                                     100 MB System
2                           105906176                                    16 MB Reserved
3                C           122683392                                237.87 GB Basic
4                           255529582592                                505 MB Recovery
5                           256059113472                              38.68 GB Basic
6                F           297587965952                             188.61 GB Basic


   DiskPath: \\?\usbstor#disk&ven_wdc_wd25&prod_00bekt-60pvmt0&rev_01.0#0123456789abcdef0124&0#{53f56307-b6bf-11d0-94f2
-00a0c91efb8b}

PartitionNumber  DriveLetter Offset                                        Size Type
---------------  ----------- ------                                        ---- ----
1                           131072                                      256 MB System
2                           268566528                                232.63 GB Unknown
3                           250050944512                                  8 MB Unknown

Thanks for another tip!

[guenther-alka]

If you want to use partitions, it is helpful to have physicaldriveXpartitionY names ex