What is an iSCSI Target?
While traditional SMB file shares (like \\server\share) allow multiple users to access files over the network, some applications—like SQL Server clusters or Hyper-V virtual machines—absolutely require “block-level” storage. They need to see a physical hard drive connected to the computer, not a network folder. iSCSI (Internet Small Computer Systems Interface) solves this. It allows you to carve out a chunk of storage on your Windows Server (the Target) and present it over standard Ethernet to another server (the Initiator), which mounts it exactly as if it were a physical SATA hard drive plugged into its own motherboard.
Step 1: Install the iSCSI Target Server Role
Log in to your storage server. Open Server Manager and launch the Add roles and features wizard.
Expand File and Storage Services > File and iSCSI Services. Check the box for iSCSI Target Server. Click Next and complete the installation.
Step 2: Create an iSCSI Virtual Disk (LUN)
Once installed, open Server Manager, click on File and Storage Services in the left column, and select iSCSI.
In the main pane, click the link that says “To create an iSCSI virtual disk, start the New iSCSI Virtual Disk Wizard”.
Select the physical volume on your server where the data will live (e.g., the D: drive). Name the virtual disk (e.g., SQL-Data-LUN). Next, specify the size of the disk (e.g., 500GB). You can choose “Dynamically expanding” to save physical space on the server until the disk actually fills up with data.
Step 3: Create the iSCSI Target
The wizard will ask you to assign this new virtual disk to an iSCSI Target. An iSCSI Target is essentially a logical access point that controls which remote computers are allowed to connect to the disk.
Select New iSCSI target and name it (e.g., Target-SQL-Cluster).
Step 4: Specify the Allowed Initiators
Security is critical; you do not want random servers mounting your SQL database drive. On the “Specify access servers” screen, click Add.
The easiest method is to enter the IP address of the client server (the Initiator) that needs to connect. Under “Enter a value for the selected type”, select IP Address, type the client’s IP (e.g., 192.168.1.55), and click OK.
Complete the wizard. Your Windows Server has now created a 500GB VHDX file and is actively broadcasting it over port 3260 to that specific IP address.
Step 5: Connect from the Client Server
Log in to the client server (the machine at 192.168.1.55). Click Start, type iSCSI Initiator, and open the app. If prompted to start the service automatically, click Yes.
In the Target tab, type the IP address of your storage server in the “Target:” box and click Quick Connect. The target name will appear, and its status will change to Connected.
If you open Disk Management (diskmgmt.msc) on this client server, a brand new 500GB “Offline” disk will instantly appear. You can bring it online, format it with NTFS or ReFS, and assign it a drive letter. It is block-level storage delivered entirely over your Ethernet network.