Technical data

3
Shared SCSI Bus Requirements and
Configurations Using UltraSCSI Hardware
A TruCluster Server cluster uses shared SCSI buses, external storage
shelves or redundant array of independent disks (RAID) controllers, and
supports disk mirroring and fast file system recovery to provide high data
availability and reliability.
This chapter discusses the following topics:
• Shared SCSI bus configuration requirements (Section 3.1)
• SCSI bus performance (Section 3.2)
• SCSI bus device identification numbers (Section 3.3)
• SCSI bus length (Section 3.4)
• SCSI bus termination (Section 3.5)
• UltraSCSI hubs (Section 3.6)
• How to configure UltraSCSI hubs with RAID array controllers
(Section 3.7)
This chapter:
• Introduces SCSI bus configuration concepts
• Describes requirements for the shared SCSI bus
• Provides procedures for cabling TruCluster Server radial configurations
using UltraSCSI hubs and:
– Dual-redundant HSZ70 or HSZ80 RAID array controllers that are
enabled for simultaneous failover
– Dual-redundant HSZ70 or HSZ80 RAID array controllers that are
enabled for multiple-bus failover
– RAID Array 3000 (RA3000) with HSZ22 controller configured for
active/active or active/passive mode.
• Provides diagrams of TruCluster Server storage configurations using
UltraSCSI hardware that is configured for radial connections
Shared SCSI Bus Requirements and Configurations Using UltraSCSI Hardware 3–1