Add and Configure a Generic SCSI Device in VMware Player

Learn how to map a host-connected physical SCSI scanner, tape drive, or other peripheral to a VMware Player guest using Generic SCSI passthrough.

A Generic SCSI Device gives a VMware Player guest operating system access to a compatible physical SCSI device connected to the host. This is a form of passthrough: VMware presents the selected host hardware to the guest as a virtual SCSI device.

The host operating system is the system running VMware Player. The guest operating system is the system installed inside the virtual machine. The guest still needs a suitable driver and, when applicable, vendor software for the physical device.

What Generic SCSI Passthrough Does

SCSI is a family of interfaces used by storage and peripheral devices, including tape drives, scanners, and some disks. A Generic SCSI Device maps one physical SCSI device from the host to one virtual SCSI device in the guest.

This is different from other VMware hardware types:

Virtual disks: Files or storage areas presented as guest disks; they are not direct access to a physical SCSI peripheral.
Virtual CD/DVD drives: Guest optical drives backed by an image file, host drive, or another configured source.
USB passthrough: Direct assignment of a USB device rather than a SCSI device. See connecting a USB device to a virtual machine.
Virtual serial ports: Emulated serial interfaces used for serial peripherals or host connections, not generic SCSI hardware. See adding a virtual serial port.

Suitable Device Scenarios

Generic SCSI passthrough can be useful when a guest must operate a compatible host-connected peripheral directly, such as:

A SCSI scanner used by a Windows guest.
A SCSI tape drive used by a Linux guest for backup or restore work.
Another supported SCSI peripheral for which the guest has a compatible driver and management application.

The guest operating system must support the physical device and have an appropriate driver. If the guest cannot identify the device, install the required guest driver or vendor software and verify that the device is supported by that operating system.

Prerequisites and Permissions

Before changing VM hardware, select the intended virtual machine in the VMware Player library. The VM should generally be powered off while adding or changing hardware.

Host Prerequisites by Platform

Windows host — Run VMware Player with administrator privileges. Confirm that the SCSI device is connected, powered on, recognized by Windows, and not being used by host software.

Linux host — Use an account with read and write access to the relevant SCSI device node. Verify device-node access, ownership, and group membership according to the distribution's device-permission model. Also confirm that the device is recognized by Linux and is not in active use.

Do not assign a device while host software is scanning, backing up, restoring, or otherwise communicating with it. Unless the hardware and applications explicitly support shared access, only one environment should use the device at a time.

Add a Generic SCSI Device

Select the virtual machine in the VMware Player library.
Open Player > Manage > Virtual Machine Settings.
Open the Hardware tab and choose Add.
Select Generic SCSI Device as the hardware type, then continue.
Choose the intended physical SCSI device from the available device list.
Choose the connection behavior, including whether to enable Connect at power on.
Finish the wizard and confirm that the new Generic SCSI Device appears in the VM hardware list.

Select VM in library → Player → Manage → Virtual Machine Settings → Hardware → Add → Generic SCSI Device → select physical device → Finish

Choose the Connection Behavior

Connect at power on automatically connects the mapped physical device whenever the VM starts. Enable it when the VM is dedicated to the peripheral, such as a tape-drive VM or a scanning workstation that normally owns its scanner.

Leave it disabled when the host occasionally needs the device. In that case, allow host applications to release the hardware, connect it to the guest when needed, and disconnect it after the workload completes.

Start and Validate the Guest Device

Start the virtual machine after adding the device.
Check the guest's hardware listing or device-management tools for the mapped SCSI hardware.
Install or configure the guest driver and any scanner, tape, or vendor management software.
Perform a low-risk test appropriate to the device.

For a scanner, use the guest scanning application to perform a detection test or a simple test scan. For a tape drive, run a non-destructive status or inventory check before attempting backup or restore operations. Avoid destructive media operations until detection and access have been confirmed.

Example: SCSI Scanner in a Windows Guest

Start VMware Player with administrator access on the Windows host.
Add a Generic SCSI Device and select the host-connected scanner.
Enable Connect at power on if this VM is dedicated to scanning.
Boot the guest and install the scanner driver or scanning application.
Run a test scan from inside the guest.

Example: SCSI Tape Drive in a Linux Guest

Verify that the Linux host user has read and write permission for the tape device.
Add the correct physical tape drive as a Generic SCSI Device.
Start the guest and verify that it detects the mapped hardware.
Install guest-side tape utilities and vendor drivers when required.
Run a non-destructive device status or inventory check before backup or restore work.

Example: Manual Connection for Occasional Host Use

Leave Connect at power on disabled.
Ensure host applications have released the peripheral.
Connect the device to the guest only for the required workload.
Disconnect it from the guest after the operation completes, before returning it to host software.

Capacity and Planning

A virtual machine can have up to 60 generic SCSI devices. Plan assignments carefully when several physical SCSI devices or multiple VMs are involved. A physical device should not be assigned to multiple active users unless the device and software explicitly support safe shared access.

Operational Cautions

Do not allow host and guest applications to access the same peripheral simultaneously unless shared access is explicitly supported.
Stop device-related workloads before changing VM hardware mappings.
Do not disconnect, power off, or reassign the physical device during an active scan, backup, restore, or other I/O operation.
Expect behavior to vary with the host platform, device driver, guest driver, hardware, and VMware compatibility.
If an operation is interrupted, verify the device and data state before reconnecting it or starting another operation.

Configuration Checklist

Host preparation — Connect and power on the device; confirm host recognition, permissions, and that no host application is using it.

VM hardware configuration — Open the selected VM's settings, choose Hardware and Add, then select Generic SCSI Device and the physical device.

Connection preference — Enable Connect at power on for a dedicated VM; otherwise use manual connection.

Guest driver setup — Start the guest and install the device driver and vendor software it requires.

Functional test — Perform a low-risk scanner detection, test scan, tape status check, or inventory operation.

Troubleshooting

Generic SCSI option or device is unavailable — The device may be disconnected, powered off, undetected, or blocked by missing host drivers or permissions. Confirm host-level detection, restart VMware Player with the required privileges, and check host drivers.

Access is denied or the device cannot be connected — Windows may require administrator access; Linux may lack read/write permission for the device node; or a host process may hold the device. Correct permissions and close host applications using the peripheral.

The guest sees the device but cannot use it — The guest may lack a compatible driver or vendor software, or the device may not be supported by the guest operating system. Install the required guest components and check guest hardware listings or logs for driver errors.

The device is unavailable after the VM starts — Connect at power on may be disabled, the hardware may have been disconnected or reassigned, or the mapping may point to another physical device. Review the Generic SCSI Device entry and verify the selected host device.

I/O operations fail or behave inconsistently — The host and guest may be competing for the device, the passthrough workload may be unsupported, or the device may have been interrupted during I/O. Use one environment at a time, update drivers, and avoid disconnecting the device during operations.

Exam-Relevant Notes

A Generic SCSI Device maps a physical host SCSI device to a virtual SCSI device in the guest.
The guest requires its own compatible driver; host visibility alone is insufficient.
Windows hosts require VMware Player administrator privileges for this configuration.
Linux hosts require read and write access to the relevant SCSI device node.
Connect at power on controls automatic connection when the VM starts.
A VM supports up to 60 generic SCSI devices.

For related hardware configuration, review adding a new virtual hard disk, configuring a USB controller, and adding a virtual serial port.