User`s guide

Table 2–3 (Cont.) Mass Storage Problems
Problem Symptom Corrective Action
SCSI bus length
exceeded
Drives may disappear
intermittently from the
show config and show
device displays.
A SCSI bus extended to the
internal StorageWorks shelf with
the backplane configured as a
single bus, cannot be extended
outside of the enclosure.
A SCSI bus extended to the
internal StorageWorks shelf with
the backplane configured as a
dual bus, can be extended 1
meter outside of the enclosure.
The entire SCSI bus length, from
terminator to terminator, must
not exceed 5 meters for single-
ended SCSI-2 at 5 MB/sec, or 3
meters for single-ended SCSI-2 at
10 MB/sec.
Terminator missing or
wrong terminator used
Read/write errors in the
console event log; storage
adapter port may fail.
Attach appropriate terminators
as needed (external SCSI
terminator for use with the
SWXCR-xx RAID controller,
12-41667-02; external SCSI
terminator for native controller,
12-37004-04 or 12-41667-02).
Note: The SCSI terminator
jumper (J49) on the system
motherboard should be set to
‘‘on’’ to enable the onboard SCSI
termination.
Extra terminator Devices produce errors or
device IDs are dropped.
Check that bus is terminated only
at beginning and end. Remove
unnecessary terminators.
Note: The SCSI terminator
jumper (J49) on the system
motherboard should be set to
‘‘on’’ to enable the onboard SCSI
termination.
SCSI storage controller
failure
Problems persist after
eliminating the problem
sources.
Replace failing EISA or PCI
storage adapter module (or
motherboard for the native SCSI
controller).
2–10 Power-Up Diagnostics and Display