2.6 RAID Array Controller Restrictions ... ............................ 2–7
2.7 SCSI Signal Converters .. ............................................ 2–8
2.8 DS-DWZZH-03 and DS-DWZZH-05 UltraSCSI Hubs .. .. ... ... . 2–9
2.9 SCSI Cables ... ......................................................... 2–9
2.10 SCSI Terminatorsand Trilink Connectors ... ... .. ................ 2–11
3 Shared SCSI Bus Requirements and Configurations UsingUltraSCSI Hardware
3.1 Shared SCSI Bus Configuration Requirements . ................. 3–2
3.2 SCSI Bus Performance .. ............................................. 3–3
3.2.1 SCSI Bus VersusSCSI Bus Segments .. ... ... ................ 3–4
3.2.2 TransmissionMethods . ... ... .. ... .............................. 3–4
3.2.3 Data Path ......................................................... 3–5
3.2.4 Bus Speed ......................................................... 3–5
3.3 SCSI Bus Device Identification Numbers . ... ... .. ............... 3–5
3.4 SCSI Bus Length ... .. ... .............................................. 3–6
3.5 Terminatingthe Shared SCSI Bus when UsingUltraSCSI
Hubs ... ... ... ........................................................... 3–7
3.6 UltraSCSI Hubs ... ... ... .............................................. 3–8
3.6.1 Using a DWZZH UltraSCSI Hub in a Cluster
Configuration ... ..... ............................................. 3–9
3.6.1.1 DS-DWZZH-03 Description . ... ............................ 3–9
3.6.1.2 DS-DWZZH-05 Description . ... ............................ 3–10
3.6.1.2.1 DS-DWZZH-05 Configuration Guidelines ... ... ... . 3–10
3.6.1.2.2 DS-DWZZH-05 Fair Arbitration .. ... ................ 3–12
3.6.1.2.3 DS-DWZZH-05 Address Configurations .. ... ... .. .. 3–13
3.6.1.2.4 SCSI Bus TerminationPower . .. ... ... ................ 3–15
3.6.1.2.5 DS-DWZZH-05 Indicators ............................. 3–15
3.6.1.3 Installing the DS-DWZZH-05 UltraSCSI Hub .. ... .. ... 3–15
3.7 Preparing the UltraSCSI Storage Configuration ................ 3–16
3.7.1 Configuring Radially Connected TruCluster Server
Clusters with UltraSCSI Hardware .. ... .. ... ................. 3–17
3.7.1.1 Preparing an HSZ70 or HSZ80 for a Shared SCSI Bus
Using TransparentFailover Mode ... .. ... ................ 3–18
3.7.1.2 Preparing a Dual-Redundant HSZ70 or HSZ80 for a
Shared SCSI Bus Using Multiple-Bus Failover ... .. ... 3–22
4 TruCluster Server System Configuration Using UltraSCSIHardware
4.1 Planning YourTruCluster Server Hardware Configuration .. . 4–2
4.2 Obtaining the Firmware Release Notes .... .. ... .. ................ 4–4
iv Contents