Dell PowerEdge 2500SC - Manual (Page 16)

SCSI Bus Interface Definitions
The basic host adapter settings are the SCSISelect settings most likely to require modification:
l 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.
l 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 if a device supports SCSI parity, consult the documentation for the device.
l Host Adapter SCSI Termination — Sets termination on the host adapter. The default setting for the AIC-7899 host adapter is Automatic. Dell recommends
that you leave this option set to the default.
Boot Device Options
The boot device options allow you to specify the device from which to boot your system:
l Boot SCSI ID — Specifies the boot channel (A or B) for the dual channel Apaptec 7899 host adapter. The default is A First.
l Boot SCSI ID — Specifies the SCSI ID of the device from which you want to boot your system. SCSI IDs are set for the hard-disk drive according to the
drive's location on the backplane board. The default setting for Boot Target ID is 0.
l 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 Multiple LUN Support is enabled (see "Advanced Configuration Settings"). The default setting is LUN 0.
SCSI Device/Configuration Settings
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."
l Sync Transfer Rate — Sets the maximum synchronous data transfer rate that the host adapter supports.
The AIC-7899 host adapter supports rates up to 160 megabytes per second (MB/sec). The default for the AIC-7899 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.)
l Initiate Wide Negotiation — Determines whether the host adapter attempts 16-bit data transfer instead of 8-bit data transfer. The default is Yes.
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.
l 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
Enable Write Back Cache Yes
BIOS Multiple LUN Support No (Enabled)
Include in BIOS Scan Yes (Enabled)
Advanced Configuration:
Reset SCSI Bus at IC Initialization Enabled
Display <Ctrl><a> Message During BIOS Initialization Enabled
Extended BIOS Translation For DOS Drivers > 1 GB Enabled
Silent/Verbose Mode Verbose
Host Adapter BIOS Enabled
Domain Validation Enabled
Support Removable Disks Under BIOS As Fixed Disks Boot Only
BIOS Support For Bootable CD-ROM Enabled
BIOS Support For Int 13 Extensions Enabled
Support For Ultra SCSI Speed Enabled
NOTE: For the full name of an abbreviation or acronym used in this table, see the " Glossary ."
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.