Generic SCSI lets a virtual machine run any SCSI device that is supported by the guest operating system in the virtual machine. Generic SCSI gives the guest operating system direct access to SCSI devices connected to the host, such as scanners and tape drives.
Using the SCSI Generic driver in Windows, VMware Workstation allows your guest operating system to operate generic SCSI devices - including scanners, tape drives and other data storage devices - in a virtual machine.
Note: In order to access host SCSI devices as Generic SCSI devices from within a virtual machine, you must run VMware Workstation as a user with administrator access.
In theory, generic SCSI is completely device independent, but VMware has discovered it is sensitive to the guest operating system, device class and specific SCSI hardware. We encourage you to try any SCSI hardware you want to use and report problems to VMware technical support.
Note: If you are using generic SCSI devices in a Windows 95, Windows 98 or Windows Me guest operating system and are experiencing problems with the devices, download the latest Mylex® (BusLogic) BT/KT-958 compatible host bus adapter from www.lsilogic.com. This driver overrides what Windows chooses as the best driver, but it corrects known problems.
To use SCSI devices in a Windows XP or Windows Server 2003 virtual machine, you need a special SCSI driver available from the download section of the VMware Web site at www.vmware.com/download. Follow the instructions on the Web site to install the driver.
Generic SCSI devices use the virtual Mylex (BusLogic) BT/KT-958 compatible host bus adapter provided by the virtual machine. Some guest operating systems guide you through installing the drivers after you install the first SCSI device in the virtual machine. On Windows NT 4.0, however, you may need to install the driver manually, if it is not already installed for a virtual SCSI disk. You should do so before you add a generic SCSI device.
To install the BusLogic driver in a Windows NT 4.0 guest, have your Windows NT installation CD available and follow these steps.
Start > Settings > Control Panel > SCSI Adapters
You can add generic SCSI devices to your virtual machine in the virtual machine settings editor. When you set up a generic SCSI device, the virtual machine must be powered off.
Start > Programs > VMware > VMware Workstation
Then choose the virtual device node where you want this device to appear in the virtual machine.
A check box under Device status allows you to specify whether the device should be connected each time the virtual machine is powered on.
To remove this device, launch the virtual machine settings editor, select the generic SCSI device, then click Remove.
Using the SCSI Generic driver in Linux, VMware Workstation allows your guest operating system to operate generic SCSI devices within a virtual machine. The SCSI Generic driver sets up a mapping for each SCSI device in /dev. Each entry starts with sg (for the SCSI Generic driver) followed by a letter. For example, /dev/sga is the first generic SCSI device.
Each entry corresponds to a SCSI device, in the order specified in
/proc/scsi/scsi, from the lowest device ID on the lowest adapter to the
highest device ID on the lowest adapter, and so on to the highest device ID on the
highest adapter. Do not enter /dev/st0 or /dev/scd0.
Note: When setting up a generic SCSI device in the virtual machine settings editor, as described later in this section, you specify the device you wish to install in the virtual machine by typing its /dev/sg entry in the Connection field. You must be logged on as a user who has permissions to use the device.
Generic SCSI requires version 2.1.36 of the SCSI Generic (sg.o) driver, which comes with kernel 2.2.14 and higher.
Under Linux some devices - specifically tape drives, disk drives and CD-ROM drives - already have a designated /dev entry (traditionally, st, sd and scd, respectively). When the SCSI Generic driver is installed, Linux also identifies these devices with corresponding sg entries in /dev - in addition to their traditional entries. VMware Workstation ensures that multiple programs are not using the same /dev/sg entry at the same time but cannot always ensure that multiple programs are not using the /dev/sg and the traditional /dev entry at the same time. It is important that you do not attempt to use the same device in both host and guest. This can cause unexpected behavior and may cause loss or corruption of data.
You must have read and write permissions on a given generic SCSI device in order to use the device within a virtual machine, even if the device is a read-only device such as a CD-ROM drive. These devices typically default to root-only permissions. Your administrator should create a group with access to read and write to these devices, then add the appropriate users to that group.
In theory, generic SCSI is completely device independent, but VMware has discovered it is sensitive to the guest operating system, device class and specific SCSI hardware. We encourage you to try any SCSI hardware you want to use and report problems to VMware technical support.
Note: If you are using generic SCSI devices in a Windows 95, Windows 98 or Windows Me guest operating system and are experiencing problems with the devices, download the latest Mylex (BusLogic) BT/KT-958 compatible host bus adapter from www.lsilogic.com. This driver overrides what Windows chooses as the best driver, but it corrects known problems. To use SCSI devices in a Windows XP or Windows Server 2003 virtual machine, you need a special SCSI driver available from the download section of the VMware Web site at .www.vmware.com/download
You can add generic SCSI devices to your virtual machine in the virtual machine settings editor. The virtual machine settings editor lets you map virtual SCSI devices to physical generic SCSI devices on the host.
When you set up a generic SCSI device, the virtual machine must be powered off.
Then choose the virtual device node where you want this device to appear in the virtual machine.
A check box under Device status allows you to specify whether the device should be connected each time the virtual machine is powered on.
To remove this device, launch the virtual machine settings editor, select the generic SCSI device, then click Remove.
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