Dual Ultra320 SCSI Host Adaptors installed in Sun Fire V440 Servers may not see devices on the SCSI Bus.

Asset ID:	1-73-1001155.1
Update Date:	2010-08-31
Keywords:

Solution Type FAB (standard) Sure

Solution 1001155.1 : Dual Ultra320 SCSI Host Adaptors installed in Sun Fire V440 Servers may not see devices on the SCSI Bus.

Related Items


Sun Fire V440 Server

Related Categories


GCS>Sun Microsystems>Sun FAB>Standard>Reactive

PreviouslyPublishedAs
201548

Product
Sun Fire V440 Server

Bug Id
<SUNBUG: 6386284>

Part

Part No: 375-3191-01
Part Description: PCI,ULTRA320,DUAL,SCSI

Part

Part No: 375-3365-01
Part Description: PCI,ULTRA320,DUAL,SCSI (RoHS)

Part

Part No: 150-2267-01
Part Description: SCSI Terminator, HD68, Single-Ended Forced Perfect

Xoption

Xoption Number: SGXPCI2SCSILM320-Z
Xoption Description: PCI,ULTRA320,DUAL,SCSI (RoHS)

Xoption

Xoption Number: SG-XPCI2SCSI-LM320
Xoption Description: PCI,ULTRA320,DUAL,SCSI

Impact

Dual Ultra320 SCSI Host Adaptors installed in Sun Fire V440 Servers may in some cases not recognize devices on the SCSI Bus. This can occur due to electrical noise on the SCSI Bus generated by the V440 power supply.

Contributing Factors

This has been observed in only a few instances, but could potentially occur with any device attached to the Dual Ultra320 SCSI HBA in a Sun Fire V440 when the HBA is run in Low Voltage Differential (LVD) mode. It can occur with either the RoHS (375-3365-01) or non-RoHS (375-3191-01) versions of the card.

Symptoms

When this issue is present, "probe-scsi" at the OBP prompt will not find attached SCSI devices.

Root Cause

The noise observed is a 90KHz periodic waveform which is part of the AC source input (power factor correction) of the power supply. This section of the power supply has not changed since FCS so all revisions of the power supply should show this issue. Checking the 5 Volt on the motherboard, it is observed that the V440 has a 250mV peak-peak noise on it. It was also observed that at the SCSI connector this same noise is larger (1.0V peak-peak). Running the HBA in Single-Ended mode reduced this noise to 580mVp-p.

Workaround

For customers who experience this issue on a Sun Fire V440 Server, it is recommended to configure the SCSI Bus for Single-Ended (SE) mode. This can be done by installing a SE SCSI terminator. The Sun part number for this terminator is 150-2267-01.

Note: Running the SCSI Bus in SE mode limits the bus speed to 40MB/sec and decreases the maximum SCSI Bus length.

Resolution

Modification History
Date: 15-MAY-2007

Corrected all references of SCSI Terminator part number from 150-1346 to 150-2267.

Previously Published As
102547
Internal Comments
Related Information

Manual: Dual Ultra320 SCSI Host Adapter Installation Guide, 817-5827

Internal Contributor/submitter
karen.vergakes@sun.com

Internal Eng Business Unit Group
KE Authors

Internal Eng Responsible Engineer
joseph.r.mazzola@sun.com

Internal Services Knowledge Engineer
pete.stauffer@sun.com

Internal Escalation ID
1-16623170

Internal Kasp FAB Legacy ID
102547

Internal Sun Alert & FAB Admin Info
Critical Category:
Significant Change Date: 2006-08-04
Avoidance: Hardware
Responsible Manager: null
Original Admin Info: null

Product_uuid
d9146f34-fb56-4421-8498-f9ecb90a1349|Sun Fire V440 Server

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