Table 4-3 Troubleshooting Disk Drive Errors - Sun Microsystems SPARCstation 20 Service Manual

b. If external devices are connected, verify that all SCSI cables and the SCSI
terminator are connected securely. The terminator must be connected to the last
physical device in the SCSI chain.
c. Check the SCSI cables to ensure there are no bent pins.
d. If after checking the previous causes, the problem is still not identified, replace
the disk drive.
e. If the problem still occurs after replacing the drive, replace the system board.
f. If replacing the disk drive and the system board does not correct the problem,
replace the internal disk drive cable assembly.
TABLE 4-3
Symptom
Read, write, or parity error
reported by the operating system
or applications
Drive fails to boot or does not
respond to commands
Slow disk drive response
34 SPARCstation 20 Service Manual • July 1996
Troubleshooting Disk Drive Errors
Corrective Action
Replace the disk drive indicated by the failure
message. The operating system identifies the Bottom
drive (SCSI address 3) as sd0 or c0t3d0 and the top
drive (SCSI address 1) as sd1 or c0t1d0. SCSI
controller or disk may be defective. See "Power-On
Does Not Succeed" on page 29 or Chapter 9.
The SCSI terminator is missing (if external devices are
connected), or the drive is defective. Make sure that
each SCSI device on the SCSI bus is assigned a unique
address. Do not use SCSI address 7 for any device
because it is reserved for the SCSI controller.
If several SCSI devices are connected to the same SCSI
bus and if some of these devices are "fast SCSI"
devices, such as the external 1.05-Gbyte disk drive,
install an FSBE/S SCSI host adapter card to the "fast
SCSI" devices and put these "fast SCSI" devices on a
separate SCSI bus to accelerate disk drive response.