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Generic SCSI on a Windows Host Operating System
Using the SCSI Generic driver in Windows, GSX Server allows your guest operating system to operate generic SCSI devices — including scanners, tape drives and other data storage devices — in a virtual machine.
Adding a Generic SCSI Device Not Detected by GSX Server (Advanced Users)
When adding a generic SCSI device to a virtual machine, if GSX Server does not display the device you want to add (for example, scanners on a Windows 2000 host or some tape backup devices), you need to add the device manually to the virtual machine's configuration file (.vmx).
Reasons GSX Server cannot detect a device include:
A driver for that device is not installed on the host.
A driver on the host prevents the device from being detected.
The virtual machine uses a device for which there are no drivers available to the host operating system.
Before you attempt the steps below, first verify whether the device driver is installed on the host. If the driver is not installed, install it then see if the device appears correctly to GSX Server. If it does not appear correctly, or if you cannot or do not want to install the driver on the host, then you need to add the device manually to the virtual machine.
When adding a device manually to the virtual machine, use scsiX:Y notation to refer to the device on the host instead of a device name GSX Server uses like CdRom0. For this type of notation, X is the SCSI bus on which the device is located on the host and Y is the target ID the device uses on the host.
Caution: Adding a device in this manner is recommended for advanced users only.
Caution: Before you add the device, you must disable the original SCSI device driver on the host. Some Windows operating systems do not process the send command from the adapter if the device driver is owning the device.
There are a few circumstances requiring you to add the device manually. Follow the steps that match your circumstance. In each case, power off the virtual machine then open the virtual machine's configuration file (.vmx) in a text editor and make the changes as described below.
1. The virtual machine does not contain any SCSI adapters or devices, or you want to add a generic SCSI device to a new virtual SCSI adapter in the virtual machine.
In this case, to add the device to the virtual machine, you need to add the following lines to the virtual machine's configuration file:
scsiZ:Y.present = "true"
scsiZ:Y.deviceType = "scsi-passthru"
scsiZ:Y.fileName = "scsiX:Y"
Define X, Y and Z as follows:
X is the SCSI bus the device uses on the host system.
Y is the target ID the device uses in the virtual machine and on the host. Use the same target ID in the virtual machine that the host already uses for the device to allow the device to work correctly.
Z is the SCSI bus the device uses in the virtual machine.
2. The virtual machine has a SCSI adapter and device and you want to add a generic SCSI device to the adapter.
In this case, to configure the device as a generic SCSI device, you need to add the following lines to the virtual machine's configuration file:
scsiZ:Y.deviceType = "scsi-passthru"
scsiZ:Y.fileName = "scsiX:Y"
Define X, Y and Z as follows:
X is the SCSI bus the device uses on the host system.
Y is the target ID the device uses in the virtual machine and on the host. Use the same target ID in the virtual machine that the host already uses for the device to allow the device to work correctly.
Z is the SCSI bus the device uses in the virtual machine.
3. The virtual machine has a SCSI adapter and generic SCSI device, but GSX Server does not recognize the device in the Add Hardware Wizard.
In this case, you need to look for a line in the configuration file that looks like:
scsiZ:Y.fileName = "<deviceName>"
Change the line to:
scsiZ:Y.fileName = "scsiX:Y"
Define X, Y and Z as follows:
X is the SCSI bus the device uses on the host system.
Y is the target ID the device uses in the virtual machine and on the host. Use the same target ID in the virtual machine that the host already uses for the device to allow the device to work correctly.
Z is the SCSI bus the device uses in the virtual machine.
For example, if the problematic device is a CD-ROM drive, the entry in the configuration file might be:
scsi0:4.fileName = "CdRom0"
If the device on the host is located on bus 2 with target ID 4, you should change this line to:
scsi0:4.fileName = "scsi2:4"
The target ID the device uses in the virtual machine must be the same as the target ID the device uses on the host system.
4. You added a generic SCSI device to the virtual machine's configuration file (
.vmx) as instructed in
step 3, but GSX Server does not recognize the device in the Add Hardware Wizard. You may experience this issue with tape drives and tape changers.
In this case, look for the line in the configuration file that looks like:
scsiZ:Y.fileName = "scsiX:Y"
Change the line to:
scsiZ:Y.fileName = "<deviceName>"
Example device names include Tape0 and Changer0.
Another alternative you can try is to uninstall or disable the device driver on the host and use the "scsiX:Y" notation in the configuration file.
Note: The SCSI bus is assigned a number by the host operating system after all IDE buses have been assigned numbers. For example, if you have 2 IDE buses, they are numbered 0 and 1. The first SCSI bus is assigned bus number 2. In the example above, you use 2 for X.
If you cannot determine the SCSI bus number on your own, you can try using a third- party tool like
winobj (which you can download for free from
www.sysinternals.com) to determine this information.
The device target ID is usually set by some jumpers or switches on the device. Refer to the owner's manual for the device for information on how to determine the target ID.