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SNC 4000 User’s Guide
49
4
If you do not have to replace an improper device, go to
Examine SCSI Cables
.
If you replaced any devices, reboot the Scalar 24.
5
After the SNC finishes booting, enter the
scsiShow
command from the service terminal.
6
Compare the list of attached devices with the physical devices.
7
If not all of the physical devices are shown, go to
Examine SCSI Cables
.
8
If all of the physical devices are shown, go to
SCSI Health Check
.
Examine SCSI Cables
1
Look for damaged cables.
Check for breaks in the cable jacket, exposed or frayed cable shield, exposed or broken wires.
2
Replace any damaged cables.
3
Look for inadequate cables.
Older SCSI cables may not be suitable for running at Ultra2/3 speeds. Be sure all cables are rated for
Ultra2/3.
4
Replace any cables not suitable for running at Ultra 2/3 speeds.
5
Check for mixed cable types.
If a SCSI bus has both round cables and flat ribbon cables, it may suffer problems when running at
Ultra2/3 speeds.
Use the same cable type consistently for all segments of the SCSI bus.
6
Replace any cables that are of the wrong type.
7
Check for unshielded cables.
An unshielded SCSI cable used external to a cabinet may cause reliability problems, due to interference
from other electrical devices.
8
Replace all unshielded cables.
9
If no cables are replaced, go to
Examine SCSI Cables
.
10
If cables were replaced, go to
SCSI Health Check
.
Examine SCSI Connectors
1
Inspect each connector to find out if pins were bent when the connector was attache
d.
2
Replace any cables that have bent pins.
3
If you did not have to replace or re-secure a SCSI cable, go to
SCSI Loop Back Test
.
4
If you replaced or re-secured a SCSI cable, reboot the Scalar 24.
5
After it finishes booting, enter the
scsiShow
command from the service terminal.
CAUTION
If in this procedure you determine that you need to remove a SCSI
cable, all I/O to the SNC must be stopped and the SNC must be turned
off.
CAUTION
Before removing a SCSI cable, all I/O to the SNC must be stopped and
the SNC must be turned off.
Summary of Contents for SNC 4000
Page 1: ...www adic com ADICSNC 4000User sGuide ADVANCED DIGITAL INFORMATION CORPORATION...
Page 10: ...4 SNC 4000 Introduction...
Page 40: ...34 Removal and Replacement Procedures...
Page 140: ...134 Service Port Command Reference...
Page 147: ...SNC 4000 User s Guide 141 fcConnPortModeGet...
Page 148: ...142 Diagnostic Command Reference...