This section describes how to install and configure the SCSI device drivers included with your system. These device drivers are designed to work with the SCSI controller on the system board. The SCSI channel is available for internal or external tape backup devices.
If you are using an optional RAID controller, see your RAID controller documentation for information on installing your SCSI device drivers.
For instructions on installing hardware devices such as diskette drives, CD drives, and tape drives, see "Installing Drives" in the Installation and Troubleshooting Guide. After the SCSI devices are installed, install and configure any SCSI device drivers to enable them to communicate with your operating system.
SCSI device drivers are provided for the following operating systems:
Microsoft® Windows NT® Server 4.0
Windows NT Server 4.0, Terminal Server
Windows NT Server 4.0, Enterprise Edition
Microsoft Windows® 2000 Server and Advanced Server
Red Hat Linux 7.2 or later
Novell® NetWare® 6.0
See "Using the Dell OpenManage Server Assistant CD" for instructions on creating a diskette of drivers for your operating system. For instructions on configuring the SCSI device drivers, see the documentation that came with your operating system. You may also need to use the SCSISelect utility, discussed in this section.
The BIOS for your system's integrated SCSI controller includes the menu-driven SCSISelect configuration utility, which allows you to change SCSI controller settings without opening the system. SCSISelect also contains SCSI disk utilities that let you perform a low-level format or verify the disk media of your SCSI hard drives.
SCSISelect uses menus to list options that you can select. To select an option, press the up- and down-arrow keys to move the cursor to the option; then press <Enter>.
In some cases, selecting an option displays another menu. You can return to the previous menu at any time by pressing <Esc>. To restore the original SCSISelect default values, press <F6>.
Default settings for the integrated SCSI controller are shown in Table C-1. These default settings are appropriate for most PCI systems. Run SCSISelect only if you need to change any of the default settings.
NOTE: To change the configuration settings, you must run the SCSISelect utility.
For situations in which you might want or need to change the settings, see the description of each setting in the following subsections. To change any of the default settings or to format or verify a disk, see "Using the SCSI Disk Utilities."
The basic host adapter settings are the SCSISelect settings most likely to require modification:
Host Adapter SCSI ID — Sets the host adapter's SCSI ID. The default setting is SCSI ID 7, which allows the host adapter to support narrow SCSI devices in addition to wide SCSI devices. Dell recommends that you leave the host adapter set to SCSI ID 7.
SCSI Parity Checking — Determines whether the host adapter verifies the accuracy of data transfer on the SCSI bus. The default setting is Enabled. You should disable SCSI Parity Checking if any SCSI device connected to the host adapter does not support SCSI parity; otherwise, leave it enabled. Most SCSI devices support SCSI parity. If you are unsure whether a device supports SCSI parity, consult the documentation for the device.
Host Adapter SCSI Termination — Sets termination on the host adapter. The default setting for the AIC-7892 host adapter is Enabled or Automatic. It is recommended that you leave this option set to the default.
The boot device options allow you to specify the device from which to boot your system:
Boot SCSI ID — Specifies the SCSI ID of the boot device.
Boot LUN Number — Allows you to specify a particular logical unit number (LUN) from which to boot your boot device if your boot device has multiple LUNs and BIOSMultiple LUN Support is enabled (see "SCSI Device Configuration Settings"). The default setting is LUN 0.
The SCSI device configuration settings allow you to configure certain parameters for each device on the SCSI bus. To configure a specific device, you must know the SCSI ID assigned to that device. If you are not sure of the SCSI ID, see "Using the SCSI Disk Utilities."
Sync Transfer Rate MB/sec — Sets the maximum synchronous data transfer rate that the host adapter supports.
The AIC-7892 host adapter supports rates up to 160 MB/sec. The default for the AIC-7892 host adapter is 160 MB/sec.
If the host adapter is set to not negotiate for synchronous data transfer, the maximum synchronous transfer rate is the maximum rate that the host adapter accepts from the device during negotiation. (This setting is standard SCSI protocol.)
Initiate Wide Negotiation — Determines whether the host adapter attempts 16-bit data transfer instead of 8-bit data transfer. The default is Yes.
NOTE: Some 8-bit SCSI devices may have trouble handling wide negotiation, which may
result in erratic behavior or a hang condition. For these devices, set Initiate Wide
Negotiation to No.
When this option is set to Yes, the host adapter attempts 16-bit data transfer. When this option is set to No, 8-bit data transfer is used unless the SCSI device itself requests wide negotiation. The effective transfer rate is doubled when 16-bit data transfer is used because the data path for wide SCSI is twice the size of normal 8-bit SCSI.
Enable Disconnection (sometimes called disconnect/reconnect) — Determines whether the host adapter allows the SCSI device to disconnect from the SCSI bus. Enabling disconnection allows the host adapter to perform other operations on the SCSI bus while the SCSI device is temporarily disconnected. The default setting is Yes.
Leave Enable Disconnection set to Yes if two or more SCSI devices are connected to the host adapter. This optimizes SCSI bus performance. If only one SCSI device is connected to the host adapter, set Enable Disconnection to No to achieve slightly better performance.
Send Start Unit Command — Determines whether the start unit command is sent to the SCSI device during the boot routine. The default is Yes.
Setting this option to Yes reduces the load on your system's power supplies by allowing the host adapter to start SCSI devices one at a time when you boot your system. When this option is set to No, the devices are allowed to start at the same time. Most devices require you to set a jumper before they can respond to this command.
NOTE: For many devices, if Send Start Unit Command is set to Yes, the boot routine time
will vary depending on how long it takes each drive to start.
Enable Write Back Cache — Signals the completion of a write request as soon as the data is in cache. Actual writing to the disk occurs at a later time. The default setting is N/C or Yes.
BIOS Multiple LUN Support — Provides support for peripherals that contain multiple SCSI devices, such as autoloading tape drives and CD-ROM changers.
NOTE: The setting for BIOS Multiple LUN Support must be No or Enabled (default) if a
tape autoloader is connected.
Include in BIOS Scan — Enables you to set whether the system BIOS scans this device during system start-up. The default is Yes.
The advanced host adapter settings should not be changed unless absolutely necessary. These values are preset, and changing them may cause conflicts with the SCSI devices.
Reset SCSI Bus at IC Initialization — Enables the SCSI bus to be reset when the controller is initialized. The default is Enabled.
Display <Ctrl><a> Message During BIOS Initialization — Determines whether the Press <CTRL><A> for SCSISelect (TM) Utility! message appears on your screen during system start-up. The default setting is Enabled. If this setting is disabled, you can still run the SCSISelect utility by pressing <Ctrl><a> after the host adapter BIOS banner appears.
Extended BIOS Translation For DOS Drives > 1 GB — Determines whether extended translation is available for SCSI hard drives with capacities greater than 1 GB. The default setting is Enabled.
NOTICE: Back up your hard drive before you change the translation scheme. All data is erased
when you change from one translation scheme to another.
The standard translation scheme for SCSI host adapters provides a maximum accessible capacity of 1 GB. To support hard drives larger than 1 GB, the 78xx series host adapters include an extended translation scheme that supports hard drives as large as 8 GB, with a maximum partition size of 2 GB under the DOS operating system.
It is not necessary to enable the Extended BIOS Translation setting if you are using another operating system, such as Novell NetWare.
When you partition a hard drive larger than 1 GB, use the MS-DOS® fdisk utility as you normally would. Because the cylinder size increases to 8 MB under extended translation, the partition size you choose must be a multiple of 8 MB. If you request a size that is not a multiple of 8 MB, fdisk rounds up to the nearest whole multiple of 8 MB.
Silent/Verbose Mode — Displays the host adapter information during system start-up. The default is Verbose.
Host Adapter BIOS — Enables or disables the host adapter BIOS. The default setting is Enabled.
NOTE: Several SCSISelect options are not valid unless the host adapter BIOS is enabled.
If you are booting from a SCSI hard drive connected to the host adapter, the BIOS must be enabled. You should disable the host adapter BIOS if the peripherals on the SCSI bus (for example, CD-ROM drives) are all controlled by device drivers and do not need the BIOS.
Domain Validation — Instructs the host adapter not to accept a negotiated speed until a validation test is successfully performed. After determining the speed that a target device is capable of, the host adapter sends a Write Buffer command to the target device. The data transfer occurs at the full speed initially. The initiator reads and tests the data and identifies any parity or cyclic redundancy check (CRC) errors. If the test fails, the initiator lowers its speed and repeats the test. In this manner, a compatible speed will be found and locked in before user data transfers begin. The default is Enabled.
Support Removable Disks Under BIOS As Fixed Disks — Controls which removable-media drives are supported by the host adapter BIOS. The default setting is Boot Only. The following choices are available.
NOTICE: If a removable-media SCSI device is controlled by the host adapter BIOS, do not
remove the media while the drive is on or you may lose data. If you want to be able to remove
media while the drive is on, install your removable-media device driver and set this option to
Disabled.
Boot Only — Only the removable-media drive designated as the boot device is treated as a hard drive.
All Disks — All removable-media drives supported by the BIOS are treated as hard drives.
Disabled — No removable-media drives are treated as hard drives. In this situation, software drivers are needed because the drives are not controlled by the BIOS.
BIOS Support For Bootable CD-ROM — Determines whether the host adapter BIOS provides support for booting from a CD drive. The default setting is Enabled.
BIOS Support For Int 13 Extensions — Determines whether the host adapter BIOS supports disks with more than 1024 cylinders. The default setting is Enabled.
To access the SCSI disk utilities, select SCSI Disk Utilities from the menu that appears when you start SCSISelect. When the option is selected, SCSISelect immediately scans the SCSI bus (to determine the devices installed) and displays a list of all SCSI IDs and the device assigned to each ID.
When you select a specific ID and device, a menu appears, displaying the Format Disk and Verify Disk Media options.
NOTICE: The Format Disk option destroys all data on the hard drive.
Format Disk — Runs a utility that allows you to perform a low-level format on a hard drive. Most SCSI disk drives are formatted at the factory and do not need to be formatted again. The Adaptec Format Disk utility is compatible with the majority of SCSI disk drives.
Verify Disk Media — Runs a utility that allows you to scan the media of a hard drive for defects. If the utility finds bad blocks on the media, it prompts you to reassign them; if you select Yes,those blocks are no longer used. You can press <Esc> at any time to exit the utility.
To exit SCSISelect, press <Esc> until a message prompts you to exit. (If you changed any 78xx series host adapter settings, you are prompted to save the changes before you exit.) At the prompt, select Yes to exit, and then press any key to reboot the system. Any changes that you made in SCSISelect take effect after the system boots. (You can select No at the prompt if you are not ready to exit SCSISelect.)
