StarWind Virtual SAN: Configuration Guide for VMware vSphere [ESXi], VSAN Deployed as a Windows-based Controller VM using GUI

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StarWind Virtual SAN (VSAN)


The purpose of this document is to guide users in implementing a high-performing and highly-available storage solution using StarWind Virtual SAN and VMware vSphere 7. It provides insights into the configuration and deployment of a storage pool optimized for virtualization workloads, achieved by mirroring server storage participating storage cluster nodes. By mirroring storage resources and optimizing I/O processing, this configuration aims to provide supreme performance for virtualized environments.


This document is intended for IT professionals, system administrators, and virtualization specialists responsible for deploying and managing storage solutions within VMware vSphere 7 environments.

Expected Result

The expected result is the successful deployment of a Hyperconverged Scenario utilizing StarWind Virtual SAN and VMware vSphere 7. Users will achieve a fault-tolerant storage pool that enhances virtualization workloads, optimizes I/O performance, and ensures high availability through multipath access.

Introduction to StarWind Virtual SAN for Hyper-V

StarWind Virtual SAN is a native Windows hypervisor-centric hardware-less VM storage solution. It creates a fully fault-tolerant and high performing storage pool built for the virtualization workloads by mirroring the existing server’s storage and RAM between the participating storage cluster nodes. The mirrored storage resources are then connected to all cluster nodes and treated just as a local storage by all hypervisors and clustered applications. High Availability (HA) is achieved by providing multipath access to all storage nodes. StarWind Virtual SAN delivers supreme performance compared to any dedicated SAN solution since it runs locally on the hypervisor and all I/O is processed by local RAM, SSD cache, and disks. This way it never gets bottlenecked by storage fabric.

StarWind VSAN System Requirements

Prior to installing StarWind Virtual SAN, please make sure that the system meets the requirements, which are available via the following link:

Recommended RAID settings for HDD and SSD disks:

Please read StarWind Virtual SAN Best Practices document for additional information:

Pre-Configuring the Servers

The diagram below illustrates the network and storage configuration of the solution.


1. ESXi hypervisor should be installed on each host.

2. StarWind VSAN should be  installed on the Windows Server operating system deployed as VM on each host.

3. The network interfaces on each node for Synchronization and iSCSI/StarWind heartbeat interfaces should be in different subnets and connected directly according to the network diagram above. Here, the 172.16.10.x subnet is used for the iSCSI/StarWind heartbeat traffic, while the 172.16.20.x subnet is used for the Synchronization traffic.

NOTE: Do not use ISCSI/Heartbeat and Synchronization channels over the same physical link. Synchronization and iSCSI/Heartbeat links and can be connected either via redundant switches or directly between the nodes.

Preparing Environment for StarWind VSAN Deployment

Configuring Networks

Configure network interfaces on each node to make sure that Synchronization and iSCSI/StarWind heartbeat interfaces are in different subnets and connected physically according to the network diagram above. All actions below should be applied to each ESXi server.
NOTE: Virtual Machine Port Group should be created for both iSCSI/ StarWind Heartbeat and the Synchronization vSwitches. VMKernel port should be created only for iSCSI traffic. Static IP addresses should be assigned to VMKernel ports.
NOTE: It is recommended to set MTU to 9000 on vSwitches and VMKernel ports for iSCSI and Synchronization traffic. Additionally, vMotion can be enabled on VMKernel ports.

1. Using the VMware ESXi web console, create two standard vSwitches: one for the iSCSI/ StarWind Heartbeat channel (vSwitch1) and the other one for the Synchronization channel (vSwitch2).

Create vSwitch

2. Create a VMKernel port for the iSCSI/ StarWind Heartbeat channel.


3. Add a Virtual Machine Port Groups on the vSwitch for iSCSI traffic (vSwtich1) and on the vSwitch for Synchronization traffic (vSwitch2).

Add port group
4. Repeat steps 1-3 for any other links intended for Synchronization and iSCSI/Heartbeat traffic on ESXi hosts.

Preparing StarWind Virtual Machines

Create Virtual Machines (VMs) on each ESXi host with supported Windows Server  OS for StarWind VSAN (see system requirements: and further StarWind VSAN installation.
StarWind VMs on ESXi hosts should be configured with the following settings:

RAM: at least 4 GB (plus the size of the RAM cache if it is planned to be used) reserved for the VM;

CPUs: at least 4 virtual processors with 2 GHz reserved;

Network adapter 1: Management

Network adapter 2: iSCSI

Network adapter 3: Sync
Network adapters for iSCSI and Sync should be of the VMXNET3 type.  Network adapter for Management should be of the E1000 type.

Hard disk 1: 100 GB for OS (recommended) – Thick Provisioned Eager Zeroed.

Hard disk 2: Depends on the storage volume to be used as shared storage – Thick Provisioned Eager Zeroed.
NOTE: Alternatively, the disk can be added to StarWind VSAN VM as RDM. The link to VMware documentation is below:

Also, if a separate RAID controller is available, it can be used as dedicated storage for StarWind VM, and RAID controller can be added to StarWind VM as a PCI device. In this case RAID volume will be available as a virtual disk in the Drives section in the Web console. Follow the instructions in the section below on how to add RAID controller as PCI device to StarWind VM.

NOTE: The Active Directory Domain Services role can be added on StarWind Virtual Machine (VM) if necessary, thus it can serve as a domain controller.
NOTE: When using StarWind with the synchronous replication feature inside of a Virtual Machine, it is recommended not to make backups and/or snapshots of the Virtual Machine with the StarWind VSAN service installed, as this could pause the StarWind Virtual Machine. Pausing the Virtual Machines while the StarWind VSAN service in under load may lead to split-brain issues in synchronous replication devices, thus to data corruption.

Configuring StarWind VMs Startup/Shutdown

1. Setup the VMs startup policy on ESXi hosts from the Manage -> System tab in the ESXi web console. In the popup window, select Yes to enable the option and set the stop action to Shut down. Click on Save to proceed.


2. To configure VM autostart, right-click on it, navigate to Autostart and click on Enable.


3. Complete the actions above on the StarWind VM located on another host.

4. Start virtual machines, install Windows Server OS and StarWind Virtual SAN.

Installing StarWind VSAN for Hyper-V

1. Download the StarWind setup executable file from the StarWind website:

2. Launch the downloaded setup file on the server to install StarWind Virtual SAN or one of its components. The Setup wizard will appear. Read and accept the License Agreement.

StarWind License agreement

3. Carefully read the information about the new features and improvements. Red text indicates warnings for users that are updating the existing software installations.

4. Select Browse to modify the installation path if necessary. Click on Next to continue.

select destination location
5. Select the following components for the minimum setup:

  • StarWind Virtual SAN Service. The StarWind Virtual SAN service is the “core” of the software. It can create iSCSI targets as well as share virtual and physical devices. The service can be managed from StarWind Management Console on any Windows computer that is on the same network. Alternatively, the service can be managed from StarWind Web Console deployed separately.
  • StarWind Management Console. Management Console is the Graphic User Interface (GUI) part of the software that controls and monitors all storage-related operations (e.g., allows users to create targets and devices on StarWind Virtual SAN servers connected to the network).
    NOTE: To manage StarWind Virtual SAN installed on a Windows Server Core edition with no GUI, StarWind Management Console should be installed on a different computer running the GUI-enabled Windows edition.

6. Specify Start Menu Folder.

Select start menu folder
 Enable the checkbox if a desktop icon needs to be created. Click on Next to continue.

8. When the license key prompt appears, choose the appropriate option:

  • request time-limited fully functional evaluation key.
  • request FREE version key.
  • relect the previously purchased commercial license key.

9. Click on the Browse button to locate the license file.

10. Review the licensing information.

11. Verify the installation settings. Click on Back to make any changes or Install to proceed with installation.

12. Enable the appropriate checkbox to launch StarWind Management Console right after the setup wizard is closed and click on Finish.

13. Repeat the installation steps on the partner node.

Creating StarWind devices

1. In the StarWind Management Console click to Add Device (advanced) button and open Add Device (advanced) Wizard.

2. Select Hard Disk Device as the type of device to be created.

3. Select Virtual Disk.

4. Specify a virtual disk Name, Location, and Size.

5. Select the Thick provisioned disk type and block size.
NOTE: Use 4096 sector size for targets, connected on Windows-based systems and 512 bytes sector size for targets, connected on Linux-based systems (ESXi/Xen/KVM).

6. Define a caching policy and specify a cache size (in MB). Also, the maximum available cache size can be specified by selecting the appropriate checkbox. Optionally, define the L2 caching policy and cache size.

Device Wizard

7. Specify Target Parameters. Select the Target Name checkbox to enter a custom target name. Otherwise, the name is generated automatically in accordance with the specified target alias.

Device Wizard StarWind

8. Click Create to add a new device and attach it to the target.

Device Wizard StarWind

9. Click Close to finish the device creation.

10. The successfully added devices appear in the StarWind Management Console.


Select the Required Replication Mode

The replication can be configured using Synchronous “Two-Way” Replication mode:
Synchronous or active-active replication ensures real-time synchronization and load balancing of data between two or three cluster nodes. Such a configuration tolerates the failure of two out of three storage nodes and enables the creation of an effective business continuity plan. With synchronous mirroring, each write operation requires control confirmation from both storage nodes. It guarantees the reliability of data transfers but is demanding in bandwidth since mirroring will not work on high-latency networks.

Synchronous “Two-Way” replication

1. Right-click the recently created device and select Replication Manager from the shortcut menu.

2. Select the Add Replica button in the top menu.

StarWind Replication Manager

3. Select Synchronous “Two-Way” replication as a replication mode.

4. Specify a partner Host name or IP address and Port Number.

Selecting the Failover Strategy

StarWind provides 2 options for configuring a failover strategy:


The Heartbeat failover strategy allows avoiding the “split-brain” scenario when the HA cluster nodes are unable to synchronize but continue to accept write commands from the initiators independently. It can occur when all synchronization and heartbeat channels disconnect simultaneously, and the partner nodes do not respond to the node’s requests. As a result, StarWind service assumes the partner nodes to be offline and continues operations on a single-node mode using data written to it.
If at least one heartbeat link is online, StarWind services can communicate with each other via this link. The device with the lowest priority will be marked as not synchronized and get subsequently blocked for the further read and write operations until the synchronization channel resumption. At the same time, the partner device on the synchronized node flushes data from the cache to the disk to preserve data integrity in case the node goes down unexpectedly. It is recommended to assign more independent heartbeat channels during the replica creation to improve system stability and avoid the “split-brain” issue.
With the heartbeat failover strategy, the storage cluster will continue working with only one StarWind node available.

Node Majority

The Node Majority failover strategy ensures the synchronization connection without any additional heartbeat links. The failure-handling process occurs when the node has detected the absence of the connection with the partner.
The main requirement for keeping the node operational is an active connection with more than half of the HA device’s nodes. Calculation of the available partners is based on their “votes”.
In case of a two-node HA storage, all nodes will be disconnected if there is a problem on the node itself, or in communication between them. Therefore, the Node Majority failover strategy requires the addition of the third Witness node or file share (SMB) which participates in the nodes count for the majority, but neither contains data on it nor is involved in processing clients’ requests. In case an HA device is replicated between 3 nodes, no Witness node is required.
With Node Majority failover strategy, failure of only one node can be tolerated. If two nodes fail, the third node will also become unavailable to clients’ requests.
Please select the required option:


1. Select Failover Strategy.

2. Select Create new Partner Device and click Next.

3. Select a partner device Location and click Next.

Select Synchronization Journal Strategy and click Next.
NOTE: There are several options – RAM-based journal (default) and Disk-based journal with failure and continuous strategy, that allow to avoid full synchronization cases.

RAM-based (default) synchronization journal is placed in RAM. Synchronization with RAM journal provides good I/O performance in any scenario. Full synchronization could occur in the cases described in this KB:

Disk-based journal placed on a separate disk from StarWind devices. It allows to avoid full synchronization for the devices where it’s configured even when StarWind service is being stopped on all nodes.
Disk-based synchronization journal should be placed on a separate, preferably faster disk from StarWind devices. SSDs and NVMe disks are recommended as the device performance is defined by the disk speed, where the journal is located. For example, it can be placed on the OS boot volume.
It is required to allocate 2 MB of disk space for the synchronization journal per 1 TB of HA device size with a disk-based journal configured and 2-way replication and 4MB per 1 TB of HA device size for 3-way replication.

Failure journal – provides good I/O performance, as a RAM-based journal, while all device nodes are in a healthy synchronized state. If a device on one node went into a not synchronized state, the disk-based journal activates and a performance drop could occur as the device performance is defined by the disk speed, where the journal is located. Fast synchronization is not guaranteed in all cases. For example, if a simultaneous hard reset of all nodes occurs, full synchronization will occur.

Continuous journal – guarantees fast synchronization and data consistency in all cases. Although, this strategy has the worst I/O performance, because of frequent write operations to the journal, located on the disk, where the journal is located.


5. Click Change Network Settings.

6. Specify the interfaces for Synchronization and Heartbeat Channels. Click OK and then click Next.

7. In Select Partner Device Initialization Mode, select Synchronize from existing Device and click Next.

8. Click Create Replica. Click Finish to close the wizard.
The successfully added device appears in StarWind Management Console.

9. Follow the same procedure for the creation of other virtual disks that will be used as storage repositories.

Node Majority

There are two ways to configure Witness for 2-nodes StarWind HA device, created with Node Majority Failover Strategy: File Share (SMB) as Witness and additional server as Witness Node.

– Creating HA device with File SHare(SMB) as Witness:

SMB Witness is a file, located on SMB share, which can be accessed by both nodes and help them to eliminate the split-brain issue in case of synchronization connection interruption between the nodes. To set up the SMB file share as a Witness for 2-nodes HA device with Node Majority Failover Strategy, perform the actions, described on this page:

– Creating HA device with Witness Node:

1. Select the Node Majority failover strategy and click Next.

Node Majority

2. Choose Create new Partner Device and click Next.

3. Specify the partner device Location and modify the target name if necessary. Click Next. Select Synchronization Journal strategy and location and click Next.

4. In Network Options for Replication, press the Change network settings button and select the synchronization channel for the HA device.

5. In Specify Interfaces for Synchronization Channels, select the checkboxes with the appropriate networks and click OK. Then click Next.

6. Select Synchronize from existing Device as the partner device initialization mode.

7. Press the Create Replica button and close the wizard.

8. The added devices will appear in StarWind Management Console.
Repeat the steps above to create other virtual disks if necessary.

Adding Witness Node

Witness node can be configured on a separate host or as a virtual machine in a cloud. It requires StarWind Virtual SAN service installed on it.
NOTE: Since the device created in this guide is replicated between 2 active nodes with the Node Majority failover strategy, a Witness node must be added to it.

1. Open StarWind Management Console, right-click on the Servers field and press the Add Server button. Add a new StarWind Server which will be used as the Witness node and click OK.

witness node

2. Right-click on the HA device with the configured Node Majority failover policy and select Replication Manager and press the Add Replica button.

3. Select Witness Node.

witness node
4. Specify the Witness node Host Name or IP address. The default Port Number is 3261.

Ad partner node
5. In Partner Device Setup, specify the Witness device Location. Optionally, modify the target name by clicking the appropriate button.

6. In Network Options for Replication, select the synchronization channel with the Witness node by clicking the Change Network Settings button.

7. Specify the interface for Synchronization and Heartbeat and click OK.

8. Click Create Replica and then close the wizard.

9. Repeat the steps above to create other virtual disks if necessary.
NOTE: To extend an Image File or a StarWind HA device to the required size, please check the article below:

Preparing Datastores

Adding Discover Portals

1. To connect the previously created devices to the ESXi host, click on the Storage -> Adapters -> Software iSCSI and in the appeared window choose the Enabled option to enable Software iSCSI storage adapter. Push the Save configuration button.


2. In the Configure iSCSI window, under Dynamic Targets, click on the Add dynamic target button to specify iSCSI interfaces.


3. Enter the iSCSI IP addresses of all StarWind nodes for the iSCSI traffic.

Add dynamic target ESXI

Add dynamic target ESXI

Confirm the actions by pressing Save configuration.

4. The result should look like in the image below.

Configure iSCSI

5. Click on the Rescan button to rescan storage.


6. Now, the previously created StarWind devices are visible to the system.

7. Repeat all the steps from this section on the other ESXi host, specifying corresponding IP addresses for the iSCSI subnet.

Creating Datastores

1. Open the Storage tab on one of your hosts and click on New Datastore.

Select creation type

2. Specify the Datastore name, select the previously discovered StarWind device, and click Next.

Select device

3. Enter datastore size and click Next.

Enter datastore size

4. Verify the settings and click Finish.

5. Add another Datastore (DS2) in the same way but select the second device for the second datastore.

6. Verify that your storages (DS1, DS2) are connected to both hosts. Otherwise, rescan the storage adapter.


Path Selection Policy changing for Datastores from Most Recently Used (VMware) to Round Robin (VMware) is added into the Rescan Script, and this action is performed automatically. For checking and changing this parameter manually, the hosts should be connected to vCenter.
Multipathing configuration can be checked only from vCenter. To check it, click the Configure button, choose the Storage Devices tab, select the device, and click the Edit Multipathing button.

StarWind edit multipath


StarWind Edit multipath

Configuring Automatic Storage Rescan

For faster paths recovery, for example, after StarWind HA device synchronization, configuring automatic storage rescan is required for each ESXi host.

1. Log in to StarWind VM and install VMware PowerCLI on each StarWind virtual machine by adding the PowerShell module (Internet connectivity is required). To do so, run the following command in PowerShell:

Install-Module -Name VMware.PowerCLI -AllowClobber


NOTE: In case of using Windows Server 2012 R2, online installation of PowerCLI requires Windows Management Framework 5.1 or upper version available on VMs. Windows Management Framework 5.1 can be downloaded from

2. Open PowerShell and change the Execution Policy to Unrestricted by running the following command:

Powershell Unrestricted

3. Create a PowerShell script which will perform an HBA rescan on the hypervisor host.

Powershell Script

In the appropriate lines, specify the IP address and login credentials of the ESXi host on which the current StarWind VM is stored and running:

$ESXiHost = “IP address”
$ESXiUser = “Login”
$ESXiPassword = “Password”

Save the script as rescan_script.ps1 to the root of the C:\ drive of the Virtual Machine.

NOTE:  In some cases the rescan script can be changed and storage rescan added for another ESXi host. Appropriate lines should be duplicated and changed with properly edited variables if required.
NOTE: In some cases, it makes sense to create a separate ESXi user for storage rescans. To create the user, please follow the steps below:

Log in to ESXi with the VMware Host Client. Click Manage, and under Security & users tab, in the Users section click Add user button. In the appeared window, enter a user name, and a password.

Create a new Role, under Roles section, and click New Role button.
Type a name for the new role. Select privileges for the role and click OK.
The following privileges might be assigned: Host – Inventory, Config, Local Cim, and Global – Settings.


Assign permission to the storage rescan user for an ESXi host  – right-click Host in the VMware Host Client inventory and click Permissions. In the appeared window click Add user.

Click the arrow next to the Select a user text box and select the user that you want to assign a role to. Click the arrow next to the Select a role text box and select a role from the list.

(Optional) Select Propagate to all children or Add as group. Click Add user and click Close.


3. Repeat all steps from this section on the other ESXi hosts.

4. Perform the configuration steps above on the partner node.

5. Go to Control Panel -> Administrative Tools -> Task Scheduler -> Create Basic Task and follow the wizard steps:

Create a Basic Task Wizard

6. Specify the task name, select When a specific event is logged, and click on Next.

Basic Task Wizard

7. Select Application in the Log dropdown, type StarWindService for the event source and 788 as the event ID. Click the Next button.

8. Choose Start a Program as the action that the task will perform and click on Next.

Basic Task Wizard

9. Type powershell.exe in the Program/script field. In the Add arguments field, type:

“ -ExecutionPolicy Bypass -NoLogo -NonInteractive -NoProfile -WindowStyle Hidden -File C:\rescan_script.ps1 ”

Basic Task Wizard

Click the Next button to continue.

10. Click Finish to exit the Wizard.

Basic Task Wizard

11. Configure the task to run with highest privileges by enabling the checkbox at the bottom of the window. Also, make sure that the “Run whether user is logged on or not” option is selected.

Rescan Properties

12. Switch to the Triggers tab. Verify that the trigger on event 788 is set up correctly.

13. Click New and add other triggers by Event ID 782, 769, 773, and 817.

New Trigger

14. All added triggers should look like in the picture below.

Rescan Esxi

15. Switch to the Actions tab and verify the parameters for the task.

Rescan Properties

Press OK and type in the credentials for the user whose rights will be used to execute the command.

16. Perform the same steps on another StarWind VM, specifying the corresponding settings.

Performance Tweaks

1. Click on the Configuration tab on all of the ESXi hosts and choose Advanced Settings.

Advanced Settings

2. Select Disk and change the Disk.DiskMaxIOSize parameter to 512.


NOTE: Changing Disk.DiskMaxIOSize to 512 might cause startup issues with Windows-based VMs, located on the datastore where specific ESX builds are installed. If the issue with VMs start appears, leave this parameter as default or update the ESXi host to the next available build.
NOTE: In certain cases, in Virtual Machine, Windows event log may report an error similar to “Reset to device, \Device\RaidPort0, was issued”. Check this KB acticle for a possible solution.


By adhering to the recommended configurations and best practices, IT professionals can establish a robust and high-performing storage solution for virtualized environments. This setup not only enhances performance but also ensures high-availability, contributing to the reliability and efficiency of VMware vSphere 7 deployments.

Hey! Don’t want to tinker with configuring all the settings? Looking for a fast-track to VSAN deployment?
Dmytro Malynka
Dmytro Malynka StarWind Virtual SAN Product Manager
We've got you covered! First off, all trial and commercial StarWind customers are eligible for installation and configuration assistance services. StarWind engineers will help you spin up the PoC setup to properly evaluate the solution and will assist with the production deployment after the purchase. Secondly, once deployed, StarWind VSAN is exceptionally easy to use and maintain. Hard to believe? Wait no more and book a StarWind VSAN demo now to see it in action!