Specifications

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Technology Overview
Xserve
Because SAS has the same physical interface as SATA and leverages the hot-plug
Apple Drive Module carrier, Xserve users can make a per-bay choice between the
SATA or SAS drive. This unusual degree of flexibility means that Xserve can be
configured for a broader range of applications and specific requirements, making
the platform a better long-term choice for corporations and data centers.
Apple Drive Modules
In Xserve, the three 3.5-inch hard drive bays support greater internal capacity and
more flexible RAID options than offered by other servers in the same class. Apple Drive
Modules are affordable and simple to add. Choose 80GB or 750GB SATA Apple Drive
Modules running at 7200 rpm, or 73GB or 300GB SAS Apple Drive Modules running
at 15,000 rpm.
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Robust hot-plug connectors in Apple Drive Modules 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 convenience is made possible
by tight integration between system hardware and software.
Apple Drive Modules feature a unique handle design for fast and easy installation;
a positive locking mechanism holds them tightly in place after insertion. The drive
carrier employs a drive mounting technique that increases drive isolation and reduces
vibration, especially important for high-performance 15,000-rpm drives. 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.
Software and Hardware RAID Options
Affordable and easy-to-install drive modules make it simple to expand Xserve
systems to meet growing storage needs over time. For even greater storage capacity
or to share storage among multiple servers, high-throughput PCI Express slots enable
users to connect to external rackmount storage and backup systems, including Fibre
Channel and SCSI devices and Apple Xserve RAID.
Software RAID in Mac OS X Server
Using software RAID built into Mac OS X Server, the three Apple Drive Modules can
be striped or mirrored for improved performance or data redundancy.
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RAID 0, or striping. Increases storage performance dramatically by distributing data
across two or three Apple Drive Modules and enabling the drives to read and write
data concurrently. Drive striping takes full advantage of the three independent drive
channels and utilizes the I/O capabilities of Mac OS X Server.
Apple Drive Modules
Xserve uses reliable, easy-to-install,
high-performance Apple Drive Modules
to provide cost-effective, high-capacity
system storage.