NOTE - the screenshots below were captured from iStorage Server version 4.35. Version 5.20 is the most recent release at the time of writing - there do not appear to have been any significant changes in the process.
Installing iStorage Server
Install using default settings -
Configuring iStorage Server
The process for creating a Simple Target using a dynamic (aka Sparse, expandable) type VHD is detailed below -
Storage > Create Target (or press Ctrl+N) -
Select Hard Disk > Next > -
Select Image File > Next > -
Select Virtual Hard Disk (VHD) > Next > -
Select Create a new image file > enter filename and path (e.g. iSCSI_target1.vhd) > set the required size > select Dynamically expanding
Next > -
Select Anonymous > Next > -
Set a Target Name: > Finish -
The device should now be displayed in the console window -
Could not open SAN device: Error
If you receive the following error when attempting to run the SANBOOT or SANHOOK commands in iPXE...
Could not open SAN device: Connection reset (http://ipxe.org/0f0a6039)
... try to Stop and (Re)start the service.
Consider disabling the service at start-up (tools > Service Settings... > iSCSI Service (tab) > disable "Auto start iSCSI service after windows startup") and manually starting as required.