I have following scenario in Windows Server 2012 iSCSI Target:
I'd like to use a chain of differencing disks in target. "Chain" means more than one level of differencing disks. I create the fixed parent disk:
New-IscsiVirtualDisk -Path d:\parent.vhd -Size 5GB
the result:
ClusterGroupName :
ComputerName : var
Description :
DiskType : Fixed
HostVolumeId : {8A822BCE-7566-11E2-93EE-001E4FCF6E08}
LocalMountDeviceId :
OriginalPath :
ParentPath :
Path : d:\parent.vhd
SerialNumber : 81034BDA-A6A1-45BD-9D94-379F210185FF
Size : 5368709120
SnapshotIds :
Status : NotConnected
VirtualDiskIndex : 813676727
The I create first level child differencing disk:
New-IscsiVirtualDisk -ParentPath d:\parent.vhd -Path d:\child1.vhd
the result is:
ClusterGroupName :
ComputerName : var
Description :
DiskType : Differencing
HostVolumeId : {8A822BCE-7566-11E2-93EE-001E4FCF6E08}
LocalMountDeviceId :
OriginalPath :
ParentPath : d:\parent.vhd
Path : d:\child1.vhd
SerialNumber : 151A2FB7-F73D-4CEE-8B52-BDB9C244EF41
Size : 5368709120
SnapshotIds :
Status : NotConnected
VirtualDiskIndex : 1615492714
The I'd like to create 2nd level child differencing disk:
New-IscsiVirtualDisk -ParentPath d:\child1.vhd -Path d:\child2.vhd
This results the following error:
New-IscsiVirtualDisk : One or more parameters are not valid. For details about possible causes, type get-help New-IscsiVirtualDisk.
At line:1 char:1
+ New-IscsiVirtualDisk -ParentPath d:\child1.vhd -Path d:\child2.vhd
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : InvalidArgument: (Microsoft.Iscsi...rd errorRecord):IscsiCmdException) [New-IscsiVirtualDisk], IscsiCmdException
+ FullyQualifiedErrorId : NewIscsiVirtualDisk_Diff:System.ArgumentException:00000000,Microsoft.Iscsi.Target.Commands.NewIscsiVirtualDiskCommand
I'm able to succesfully create 2nd level child disk using New-VHD cmdlet, but then I can't import resulting disk:
Import-IscsiVirtualDisk -Path D:\child2.vhd
Import-IscsiVirtualDisk : Unable to import the virtual disk. The differencing VHD file is probably not 4K aligned.
At line:1 char:1
+ Import-IscsiVirtualDisk -Path D:\child2.vhd
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : InvalidOperation: (Microsoft.Iscsi...rd errorRecord):IscsiCmdException) [Import-IscsiVirtualDisk], IscsiCmdException
+ FullyQualifiedErrorId : ImportIscsiVirtualDisk:System.Runtime.InteropServices.COMException:80070032,Microsoft.Iscsi.Target.Commands.ImportIscsiVirtualDiskCommand
It seems that it isn't the 4K align problem:
Convert-IscsiVirtualDisk -DestinationPath d:\child2new.vhd -Path d:\child2.vhd
WARNING: No conversion is needed because the Source VHD is not a differencing VHD or it is already 4K aligned.
I can't find the way to make it or find clear information that it is impossible.