Fujitsu PRIMERGY TX120 User Manual page 193

PRIMERGY TX120 User's Guide
Head cleaning
Airborne dust and dust from the magnetic media can collect on the head of the magnetic tape device. To
remove this dust, head cleaning must be implemented. Implement head cleaning when the device
displays a cleaning request. Particularly DDS devices require periodic head cleaning, otherwise dust can
cling to the magnetic head, creating a situation that cannot be cleaned with standard head cleaning
methods, and eventually render the device useless. Also note that the cleaning media has a limit on how
many times it can be used. Using cleaning media that exceeded its lifespan will have no cleaning effect.
Note these points especially when performing automatic backups with library devices.
Managing media lifespan
Media is a consumable product that must be replaced regularly. Continued use of media exceeding its
lifespan can have negative effects on the device (e.g. increase the speed of dust accumulation). The
lifespan of media varies depending on the environment and operation condition of the device, the type of
backup software used, and other operation conditions, however, it is recommended that they be replaced
sooner than later.
To manage the lifespan, write the use start date on the media.
Rotating media
When using a single media cartridge repeatedly, backup data can be temporarily lost in the event the
backup fails. Also if the hard disk fails during backup, the backup data cannot be recovered. Perform
backup operations using multiple mediums on a rotating basis.
Avoid leaving media in devices
Because the magnetic recording surface of the device is exposed, media can easily affected by airborne
dust when left inserted for a long period of time. Insert the media before using it, and remove the media
after use, and restore it in its case. Also note that some tape devices write management information to
the tape when ejecting the media. If the power were to go out when the media is still in the device, this
writing process will not be performed and the media may become corrupted.
To avoid this, remove the media from the device when turning off the server/device.
Verifying data after a backup
Some backup software products provide data verification functions after a backup is completed. Such
functions will read and verify the data written to the media after a backup is completed. This will
increase the usage of the media, thus reducing the number of times it can be used for backups.
Depending on the hardware being used, some devices perform "read after write" operations on data; note
the points of this section as necessary.
Ejecting media after a backup
Some backup software products provide functions for ejecting media after a backup is completed. Such
functions will rewind the tape after a backup is completed and then eject the media from the drive.
Be sure to execute this function for autoloader/library devices. Depending on the structure of some
servers, this function may cause the media to eject from an internal device of the server and hit the
chassis door. If this is the case, open the door when ejecting, or do not eject the media.
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