IBM System Storage TS2900, Руководство по установке, эксплуатации и обслуживанию

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Chapter 1. Product Description
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Network Time Protocol (NTP)
NTP is an Internet standard protocol that assures accurate synchronization of
computer clock times in a network of computers. Running as a continuous
background client program on a computer, NTP sends periodic time requests to a
server, obtaining server time stamps, and using them to adjust the client’s clock.
Ultrium Tape Drives
The TS2900 Tape Autoloader supports the Ultrium 3 (3572-3SH) and Ultrium 4
(3572-S4H) Half-High Tape Drives.
The Ultrium 3 and Ultrium 4 Half-High Tape Drives support the Serial Attached SCSI
(SAS) interface. They both have one Mini-SAS (SFF-8088) connector.
Figure 1-6. Ultrium Half-High Tape Drive
Speed Matching
To improve system performance, the Ultrium 3 and Ultrium 4 Tape Drives use a
technique called speed matching to dynamically adjust its native (uncompressed)
data rate to the slower data rate of the attached server.
Channel Calibration
The channel calibration feature of the Ultrium 3 and Ultrium 4 Tape Drives
customizes each read/write data channel for optimum performance. The
customization enables compensation for variations in the recording channel transfer
function, media characteristics, and read/write head characteristics.
Power Management
The Ultrium 3 and Ultrium 4 Tape Drives feature a power management function that
controls the drive’s electronics so that part of the electronics completely turn OFF
when circuit functions are not needed for the drive’s operation.
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