IBM TS2280, Руководство по установке, эксплуатации и обслуживанию

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Table 2. Performance parameters
Ultrium Generation Media
Generation 8 media Generation 7 media
Speed matching data rates (MB/sec)
365.0 306.0
341.0 287.52
318.0 268.56
306.4 250.66
273.0 231.86
249.5 213.06
226.0 194.26
203.0 175.46
180.0 157.67
157.5 138.52
135.0 120.11
112.0 101.46
If the server's net (compressed) data rate is between two of the preceding native data rates, the drive
calculates the appropriate data rate at which to operate. Speed matching dramatically reduces backhitch,
the condition that occurs when a tape stops, reverses, and restarts motion. A backhitch is usually the
result of a mismatch between the data rates of the server and the drive.
Channel calibration
System performance is further optimized by a feature that is called channel calibration, in which the drive
automatically customizes each read/write data channel to compensate for variations in such things as the
recording channel 's transfer function, the media, and characteristics of the drive head.
Data cartridge capacity scaling
The SET CAPACITY SCSI command enables a customer to capacity scale a data cartridge to enable faster
random access. As an example, a customer can capacity scale a data cartridge to 20% of its normal length
that improves the average access time by almost a factor of 5. However, it also reduces the native
capacity of the tape to 1200 GB.
Encryption
The IBM TS2280 Tape Drive supports host Application Managed Encryption (AME), with T10 encryption
methods. Data encryption is supported by LTO Ultrium 4 and later data cartridges only.
The encryption-enabled drive contains the necessary hardware and firmware to encrypt and decrypt host
tape application data. Encryption policy and encryption keys are provided by the host application. A
drive digital certificate is installed at manufacturing time. Each drive receives a unique serial number and
certificate. The T10 Application can validate each drive instance by checking the drive's digital certificate.
Application-managed encryption is supported on AIX
®
, Windows Server, Linux, and Solaris. Encryption
requires current device drivers, available on the website https://www-945.ibm.com/support/fixcentral.
For details, see the IBM Tape Device Drivers Encryption Support documentation, and the IBM LTO Ultrium
Tape Drive SCSI Reference documentation.
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IBM TS2280: Setup, Operator, and Service Guide Machine Type 3580 Model H8S