Specifications

causing unavailability or performance degradation of the surviving drives—a common
problem with multidrive SCSI implementations. The end result is a storage architecture
that provides tremendous throughput and excellent storage scalability.
1 disk JBOD
2 disk RAID 1
2 disk RAID 0
3 disk RAID 0
1 disk JBOD
2 disk RAID 1
2 disk RAID 0
3 disk RAID 5
56MB/s
58MB/s
113MB/s
165MB/s
57MB/s
58MB/s
74MB/s
67MB/s
Software RAID
Hardware RAID Card
25MB/s 50MB/s 75MB/s 100MB/s 125MB/s 150MB/s 175MB/s
Hot-plug Apple Drive Modules
The three Xserve drive bays
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provide affordable storage expansion using 80GB, 250GB,
or 400GB SATA Apple Drive Modules.
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Apple Drive Modules feature robust hot-plug con-
nectors called Single Connector Attachment (SCA) II that protect the connecting pins
from bending when drives are inserted or removed. Hot plugging allows administrators
to add storage without bringing down the server: Insert a new Apple Drive Module
at any time and it’s instantly available to the server. This flexibility is made possible by
tight integration between system hardware and software.
Apple Drive Modules feature a unique handle design for fast, easy installation and a
positive locking mechanism to hold them tightly in place after insertion. The drive
carrier employs a drive mounting technique that increases drive isolation and reduces
vibration. Carefully tested and qualified to ensure maximum performance and reliability,
Apple Drive Modules work seamlessly with the sophisticated Xserve monitoring sensors
and Server Monitor remote monitoring software.
Monitoring of drive health
Xserve hardware and software work together to provide industry-leading remote
monitoring and alert capabilities. The server operating system reads Self-Monitoring,
Analysis, and Reporting Technology (SMART) data from each hard drive. SMART data
allows the drive to report its health and enables Server Monitor software to warn the
administrator of a prefailure condition—providing the opportunity to back up critical
data and replace the hard drive before a failure occurs. For local monitoring, each
Apple Drive Module has two LEDs, one for drive activity and one for drive health.
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Technology Overview
Xserve G5
Apple Drive Module
Xserve G5 uses reliable, high-performance
Apple Drive Modules to provide cost-
effective, high-capacity system storage.
Xserve G5 Storage Performance
Software and hardware RAID
Testing conducted by Apple in November 2004 using preproduction Xserve G5 systems. Apple conducted disk
throughput testing using Iometer, Mac OS X v10.3.4, and 400GB drive modules.