Owner's manual

SCSI bus information
Select a SCSI device from the SCSI controller submenu to display more information about the
device. The following information might appear depending on the type of device:
• Parity Errors—Displays the number of parity errors that occurred on the SCSI bus while the
bus was processing commands. The error count is kept from the time the SCSI Hardware
Interface Driver was loaded.
Parity errors might occasionally occur over time. If this number rises dramatically, and you
suspect a problem, complete the following steps:
1. Ensure that the cables are not damaged and that they are intact and properly shielded
from possible RFI.
2. Ensure that all required terminating resistors on all devices on the SCSI bus are present.
3. Ensure that each device on the SCSI bus has a unique SCSI ID.
• Phase Errors—Displays the number of times the SCSI bus entered an invalid operating state
while processing commands. The number of errors is counted from the time the SCSI Hardware
Interface Driver was loaded.
If you see any phase errors, the device might have a problem. Phase errors can be caused
by a device that is not operating correctly. If the phase errors continue to increase, replace
the device.
• Select Timeouts—Displays the number of times the controller attempted to start communications
with a device and received no response from the device. The number of errors is counted from
the time the SCSI Hardware Interface Driver was loaded.
The number of select timeouts should always be 0. Any other number of timeouts might indicate
a problem with the device. The SCSI controller attempts to reset the device, but if the value
continues to increase, power cycle the device.
A large number for this item does not indicate a problem. It shows that the device does not
support certain advanced SCSI commands that the device driver issued.
• Message Rejects—Displays the number of times the device rejected a command because the
device does not support the specific operation. The number of errors is counted since the SCSI
Hardware Interface Driver was loaded.
• Physical Width—Displays the actual width of the data transfer bus for this device. The following
values are valid:
◦ Narrow (8 bits)—The device supports a narrow 8-bit data transfer bus.
◦ Wide (16 bits)—The device supports a wide 16-bit data transfer bus.
◦ Unknown—The Storage Agents are unable to determine the physical data transfer width
for this device.
• Current Width—Displays the width of the data transfer bus that was negotiated between the
controller and the device. If this value is less than the device physical data bus width, the
Storage agent 95